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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

(Rule 14a-101)

INFORMATION REQUIRED IN PROXY STATEMENT

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

Filed by the Registrant ☒ Filed by a Party other than the Registrant ☐

Check the appropriate box:


☐☒		Preliminary Proxy Statement

☐		Confidential, For Use of the Commission Only (as permitted by 14a-6(e)(2))

☒☐	Definitive Proxy Statement

☐		Definitive Additional Materials

☐		Soliciting Material Pursuant To §240.14a-12

ARROWHEAD PHARMACEUTICALS, INC.

(Name of Registrant as Specified in Its Charter)

(Name of Person(s) Filing Proxy Statement if other than the Registrant)

Payment of filing fee (Check the appropriate box):

☒

No fee required.

☐

Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.

(1)

Title of each class of securities to which transaction applies:

(2)

Aggregate number of securities to which transaction applies:

(3)

Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):

(4)

Proposed maximum aggregate value of transaction:

(5)

Total fee paid:

☐

Fee paid previously with preliminary materials.

☐

Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

(1)

Amount Previously Paid:

(2)

Form, Schedule or Registration Statement No.:

(3)

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(4)

Date filed:

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PRELIMINARY PROXY SUBJECT TO COMPLETION

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Notice of Annual Meeting of Stockholders

To Be Held on Thursday, March ~~19, 2020~~

16, 2023

Your vote is important, whether or not you expect to attend the Annual Meeting of Stockholders. Stockholders of record are urged to vote via the Internet or telephone as instructed, or if you are voting by mail, to mark, sign and date and promptly return the proxy in the postage-prepaid return envelope provided.

Voting promptly will help avoid the additional expense of further solicitation to assure a quorum at the meeting.

Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to vote at the meeting, you must obtain a proxy issued in your name from that record holder.

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be Held on Thursday, March ~~19, 2020:~~

16, 2023:

You may access the following proxy materials at
www.proxyvote.com before the meeting and www.virtualshareholdermeeting.com/~~ARWR2020~~

ARWR2023 during the meeting.

• Notice of the ~~2020~~2023 Annual Meeting of Stockholders;

• Company’s ~~2020~~2023 Proxy Statement;

• Company’s Annual Report on Form10-K for the year ended September 30, ~~2019;~~2022; and

• Form of Proxy Card

TO THE STOCKHOLDERS OF ARROWHEAD PHARMACEUTICALS, INC.:

NOTICE IS HEREBY GIVEN that the ~~2020~~2023 Annual Meeting of Stockholders of Arrowhead Pharmaceuticals, Inc., a Delaware corporation (the “Company” or “Arrowhead”), will be held on Thursday, March ~~19, 2020,~~16, 2023, at 10:00 a.m., Pacific time (the “Annual Meeting”). This year’s meeting will be a completely “virtual” meeting of stockholders. You can attend the Annual Meeting online, vote your shares electronically, and submit your questions during the Annual Meeting by visiting www.virtualshareholdermeeting.com/~~ARWR2020.~~ARWR2023. Prior to the Annual Meeting, you will be able to vote at ~~www.proxyvote.com~~www.proxyvote.com. The Annual Meeting will be held for the purpose of considering and voting upon the following ~~proposals:~~

proposals, as more fully described in the accompanying Proxy Statement:

1. To elect the ~~six~~eight directors named in the Proxy Statement to serve as members of the Company’s Board of Directors until the next Annual Meeting or until their successors are elected;

2. To conduct an advisory(non-binding) vote to approve executive compensation;

3. To approve an amendment to the Company’s Amended and Restated~~By-Laws~~ Certificate of Incorporation to ~~implement a majority vote standard in uncontested elections~~increase the number of ~~directors; and~~

authorized shares of common stock;

4. To ratify the selection of Rose, Snyder & Jacobs LLP as independent auditors of the Company for the fiscal year ending September 30, ~~2020;~~

2023; and

5. To transact any other matters that may properly come before the Annual Meeting or any adjournments or postponements thereof.

The foregoing items of business are more fully described in the Proxy Statement accompanying this Notice. Proposal No. 1 relates solely to the election of the ~~six~~eight directors nominated by the Board of Directors and does not include any other matters relating to the election of directors, including, without limitation, the election of directors nominated by any stockholder of the Company.

All stockholders of record are cordially invited to attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/~~ARWR2020. We anticipate~~ARWR2023. Instructions for accessing the virtual Annual Meeting are provided in the Proxy Statement. In the event of a technical malfunction or other situation that the meeting chair determines may affect the ability of the Annual Meeting to satisfy the requirements for a meeting of stockholders to be held by means of remote communication under the Delaware General Corporation Law, or that otherwise makes it advisable to adjourn the Annual Meeting, the chair or secretary of the Annual Meeting will convene the meeting at 10:30 a.m., Pacific Time on the date specified above and at the Company’s address specified below solely for the purpose of adjourning the meeting to reconvene at a date, time and physical or ~~about January 28, 2020,~~virtual location announced by the meeting chair. Under either of the foregoing circumstances, we will ~~mail our stockholders a Notice Regarding~~post information regarding the ~~Availability of Proxy Materials (the “Notice of Internet Availability”) containing instructions~~announcement on ~~how to access our 2020 Proxy Statement and 2019 Annual Report on Form10-K~~ ~~and to vote online. You will need to have your16-digit~~ ~~Control Number included on your Notice of Internet Availability or your proxy card (if you received a printed copy~~the Investors page of the ~~proxy materials) to join the Annual Meeting.~~

Company’s website at ir.arrowheadpharma.com.

If you prefer to receive paper copies of our proxy materials, please follow the instructions included in the Notice of Internet Availability. To ensure your representation at the meeting, you are urged to vote via the Internet or telephone as instructed in the Notice of Internet Availability, or to mark, sign, date and return the proxy card as promptly as possible in the postage-prepaid envelope enclosed for that purpose. Any stockholder of record attending the Annual Meeting may vote at the Annual Meeting even if such stockholder has previously returned a proxy. Each stockholder may appoint only one proxy holder to attend the Annual Meeting on his or her behalf. Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to vote at the meeting, you must obtain a proxy issued in your name from that record holder.

/s/ Patrick O’Brien

Patrick O’Brien

Secretary

Pasadena, California

January ~~28, 2020~~

30, 2023

Arrowhead Pharmaceuticals, Inc.●177 E. Colorado Blvd., Suite 700●Pasadena, California 91105

~~2020~~Table of Contents

2023 PROXY STATEMENT Table of Contents

Table of Contents


General Information Concerning Solicitation and Voting			1
Record Date			12
Revocability of Proxies			12
Voting and Solicitation			12
Quorum; Abstentions; Broker Non-Votes			2
Deadline for Receipt of Stockholder Proposals			23

Proposal One — Election of Directors			34
Board Composition and Nominating Process			711
Corporate Governance, ~~Policies~~Environmental and ~~Practices~~Social Commitment			713
Stockholder Communications with Directors			814
Board Meetings and Committees			814

Director Compensation			1016

Proposal Two — Advisory Vote to Approve Executive Compensation			1217

~~Proposal Three — Amendment to Bylaws to Elect Directors by a Majority Vote~~		13

Executive Compensation		1418
Compensation Discussion and Analysis			1418
Our Company			14	18
Business Development			15	19
Platform			15	20
Pipeline			15	21
Executive Compensation Philosophy			21	31
Executive Compensation Program Design			21	31
Governance of Executive Compensation Program			22	32
Individual Compensation Elements			24	34
Employment Arrangements			29	40
Post-Employment Compensation Arrangements			29	40
Other Compensation Policies and Practices			30	40
Tax and Accounting Considerations			31	41
Compensation Risk Assessment			32	43

Compensation Tables			3344

Proposal Three - Approval of Amendment to Amended and Restated Certificate Of Incorporation To Increase The Number Of Authorized Shares Of Common Stock	53

Proposal Four — Ratification of Appointment of Independent Auditors			3955

Audit Fees			4056

Report of the Audit Committee			4157

Voting Securities of Principal Stockholders and Management			4258

Equity Compensation Plan Information			4359

Review and Approval of Related-Party Transactions			4661

Certain Relationships and Related Transactions, and Director Independence			4762


~~Exhibit A — Amended and Restated Bylaws of Arrowhead Pharmaceuticals, Inc.~~			~~A-1~~

~~2020~~Table of Contents
2023 PROXY STATEMENT General Information Concerning Solicitation and Voting

ARROWHEAD PHARMACEUTICALS, INC.

177 E. Colorado Blvd., Suite 700

Pasadena, California 91105

(626)304-3400

PROXY STATEMENT

FOR ANNUAL MEETING OF STOCKHOLDERS

To be held on Thursday, March ~~19, 2020~~

16, 2023

General Information Concerning Solicitation and Voting

The enclosed Proxy is solicited on behalf of Arrowhead Pharmaceuticals, Inc. (the “Company” or “Arrowhead”) for use at the ~~2020~~2023 Annual Meeting of Stockholders (the “Annual Meeting”) to be held on Thursday, March ~~19, 2020~~16, 2023 at 10:00 a.m., Pacific time, and at any adjournment(s) or postponement(s) thereof, for the purposes set forth herein and in the accompanying Notice of Annual Meeting of Stockholders (the “Notice”). ~~This year’s meeting will be a completely “virtual” meeting of stockholders. You can attend~~The Company anticipates that the ~~Annual Meeting online, vote your shares electronically, and submit your questions during the Annual Meeting, by visiting www.virtualshareholdermeeting.com/ARWR2020. You will need to have your16-digit~~ ~~Control Number included on your~~ Notice Regarding the Availability of Proxy Materials (the “Notice of Internet Availability”) ~~or your proxy card (if you received a printed copy of the proxy materials) to join the Annual Meeting.~~

~~The Company anticipates that the Notice of Internet Availability~~ in connection with these proxy solicitation materials will first be mailed on or about January ~~28, 2020~~30, 2023 to all stockholders entitled to vote at the Annual Meeting and we will post our proxy materials on the website referenced in the Notice of Internet Availability. As more fully described in the Notice of Internet Availability, all stockholders may choose to access our proxy materials on the website referred to in the Notice of Internet Availability or may request to receive a printed set of our proxy materials.

This year’s meeting will be a completely “virtual” meeting of stockholders. If you were a stockholder as of the close of business on the Record Date (as defined below), you can attend the Annual Meeting online, vote your shares electronically, and submit your questions and view our list of stockholders as of the Record Date during the Annual Meeting, by visiting www.virtualshareholdermeeting.com/ARWR2023. You will need to have your 16-digit Control Number included on your Notice of Internet Availability or your proxy card (if you received a printed copy of the proxy materials) to join the Annual Meeting. If your shares are held in street name and your voting instruction form or Notice of Internet Availability indicates that you may vote those shares through www.proxyvote.com, then you may access, participate in, and vote at the Annual Meeting with the 16-digit access code indicated on that voting instruction form or Notice. Otherwise, stockholders who hold their shares in street name should contact their bank, broker or other nominee (preferably at least five days before the Annual Meeting) and obtain a “legal proxy” in order to be able to attend, participate in or vote at the Annual Meeting.

The meeting webcast will begin promptly at 10:00 a.m. Pacific Time. Online check-in will begin approximately 15 minutes before then and we encourage you to allow ample time for check-in procedures. If you experience technical difficulties during the check-in process or during the meeting, please call the number listed on the meeting website for technical support.

We will endeavor to answer as many stockholder-submitted questions as time permits that comply with the Annual Meeting rules of conduct. We reserve the right to edit profanity or other inappropriate language and to exclude questions regarding topics that are not pertinent to meeting matters or Company business. If we receive substantially similar questions, we may group such questions together and provide a single response to avoid repetition. Additional information regarding the rules and procedures for participating in the Annual Meeting will be set forth in our meeting rules of conduct, which stockholders can view during the meeting at the meeting website.

By hosting the Annual Meeting virtually, we believe we are able to expand access, improve communication and lower costs while reducing the environmental impact of the meeting.


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2023 PROXY STATEMENT General Information Concerning Solicitation and Voting

Record Date

Only holders of record of our common stock at the close of business on January ~~22, 2020~~20, 2023 (the “Record Date”) are entitled to notice of the Annual Meeting and to vote at the Annual Meeting. On that date, the Company had outstanding ~~101,562,158~~106,706,695 shares of common stock (“Common Stock”).

Revocability of Proxies

Any proxy given by a stockholder of record pursuant to this solicitation may be revoked by the person giving it at any time before its use by delivering to the Secretary of the Company, at or before the taking of the vote at the Annual Meeting, a written notice of revocation or a duly executed proxy bearing a later date or by attending the Annual Meeting and voting ~~in person.~~electronically. Stockholders may also revoke their proxy by entering a new vote over the Internet or by telephone.

Voting and Solicitation

Each share of the Company’s Common Stock is entitled to one vote on all matters presented at the Annual Meeting. Each stockholder may appoint only one proxy holder or representative to attend the Annual Meeting on his or her behalf. Stockholders do not have the right to cumulate their votes in the election of directors. Shares of Common Stock represented by properly executed proxies will, unless such proxies have been previously revoked, be voted in accordance with the instructions indicated thereon. In the absence of specific instructions to the contrary, properly executed proxies will be voted FOR the Proposals 1, 2, 3, and 4 and submitted to a vote of stockholders at the Annual Meeting pursuant to this proxy statement. No business other than that set forth in the accompanying Notice of Annual Meeting of Stockholders is expected to come before the Annual Meeting. Should any other matter requiring a vote of stockholders properly arise, the persons named in the enclosed form of proxy will vote ~~such proxy~~ in accordance with ~~the recommendation of the Board of Directors (the “~~~~Board~~~~”).~~

their best judgment.

If you will not be able to attend the Annual Meeting to vote, ~~in person,~~ you may vote your shares via the Internet or by telephone or by mail as set forth in the Notice.


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~~2020 PROXY STATEMENT~~ ~~General Information Concerning Solicitation and Voting~~

The Company has engaged a proxy solicitor, ~~Alliance Advisors,~~Okapi Partners, LLC, to encourage voting by our stockholders. It is estimated that the total cost for the solicitation campaign will be approximately ~~$10,000.~~$15,000. Proxies may also be solicited by certain of the directors, officers and employees of the Company, without additional compensation. The Company will bear the costs of solicitation. In addition, the Company expects to reimburse brokerage firms and other persons representing beneficial owners of shares for their expenses in forwarding solicitation materials to such beneficial owners.

If your shares are held in a street name, the voting instruction form sent to you by your broker, bank or other nominee should indicate whether the institution has a process for beneficial holders to provide voting instructions over the Internet or by telephone. If your bank or brokerage firm gives you this opportunity, the voting instructions from the bank or brokerage firm that accompany this proxy statement will tell you how to use the Internet or telephone to direct the vote of shares held in your account. If your voting instruction form does not include Internet or telephone information, please complete and return the voting instruction form in the self-addressed, postage-paid envelope provided by your broker. Stockholders who vote by proxy over the Internet or by telephone need not return a proxy card or voting instruction form by mail.

Quorum; Abstentions; BrokerNon-Votes

The required quorum for the transaction of business at the Annual Meeting is a majority of the votes eligible to be cast by holders of shares of Common Stock issued and outstanding on the Record Date. Shares that are voted “FOR,” “AGAINST” or “ABSTAIN” on a matter are treated as being present at the meeting for purposes of establishing a quorum with respect to such matter. ~~For certain proposals, brokers may not have discretionary authority to vote on a particular matter if they have not received specific instructions from~~If you are the beneficial owner ~~of the shares (“~~~~brokernon-votes~~~~”). In accordance with the rules of Nasdaq, banks, brokerage firms~~ and ~~other nominees who hold Arrowhead shares in street name for their customers have authority~~do not direct your broker, fiduciary, or custodian how to vote ~~on “routine” proposals when they have not received instructions from beneficial owners. However, banks, brokerage firms and other nominees are precluded from exercising their voting discretion~~your shares, your broker, fiduciary, or custodian will only be able to vote your shares with respect to proposals considered to be “routine.” Your broker, fiduciary, or custodian is not entitled to vote your shares with respect to “non-routine” proposals (“broker non-votes”). Whether a proposal is considered routine or non-routine is subject to stock exchange rules. Even with respect to routine matters, some brokers are choosing not to exercise discretionary voting authority. As a result, we urge you to direct your broker, fiduciary, or custodian how to ~~matters.~~


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2023 PROXY STATEMENT General Information Concerning Solicitation and Voting

vote your shares on all proposals to ensure that your vote is counted. Shares subject to a brokernon-vote will be counted as present for the purpose of determining the presence or absence of a quorum for the transaction of business at the Annual Meeting; the effect of abstentions and brokernon-votes on the proposals presented herein is discussed below.

With regard to the election of directors, votes may be cast ~~in favor of a~~“FOR,” “AGAINST” or “ABSTAIN” for each director ~~nominee or withheld.~~nominee. Because directors are elected by ~~plurality,~~a majority of votes cast in an uncontested election, abstentions from voting and brokernon-votes, ~~will be entirely excluded from the vote and~~ if any, will have no effect on its outcome. If a quorum is present at the meeting, the nominees receiving ~~the greatest number of~~more “FOR” votes ~~up to six directors,~~than “AGAINST” votes will be elected. Because Proposal Nos. 2 3 and 4 must be approved by the affirmative vote of a majority of the shares of Common Stock entitled to vote thereon and present in person or by proxy at the Annual Meeting (the “Required Vote”), abstentions ~~will be counted in tabulations of the votes cast on each such proposal and~~ will have the same effect as a vote ~~against~~“AGAINST” the proposal, whereas brokernon-votes, ~~will be excluded from the vote and~~ if any, will have no effect on its outcome.

With regard to Proposal 3, the affirmative vote of at least a majority of the voting power of the outstanding shares of Common Stock entitled to vote thereon is required to amend the Company’s Amended and Restated Certificate of Incorporation to effect the authorized share increase. For this purpose, abstentions and broker non-votes, if any, will have the same effect as a vote “AGAINST” the proposal.

Deadline for Receipt of Stockholder Proposals

~~Any stockholder who meets the requirements of~~

To be considered for inclusion in the proxy ~~rules under~~statement and proxy card for the Company’s 2024 Annual Meeting of Stockholders, proposals of stockholders pursuant to Rule 14a-8 of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), ~~who intends~~and stockholder director nominations pursuant to ~~present a proposal at~~the proxy access provisions of the Company’s 2021 Annual Meeting of Stockholders must ensure that the proposal is received by the Corporate Secretary at Arrowhead Pharmaceuticals, Inc., 177 E. Colorado Blvd., Suite 700, Pasadena, CA 91105, not later than October 1, 2020, in order to be considered for inclusion in our proxy materials for that meeting; provided, however, that if the Company’s 2021 Annual Meeting of Stockholders is held before February 17, 2021 or after April 18, 2021, you must provide specified information to us a reasonable time before we begin to print and send our proxy statement for our 2021 Annual Meeting. Proposals received after the specified dates may be excluded from the Company’s proxy statement.

~~Additionally, our~~ Amended and Restated Bylaws (“Bylaws”), must be submitted in writing to our Corporate Secretary at the address set forth on the first page of this Proxy Statement. Such proposals and nominations must be received by us not later than our close of business (5:00 p.m. Pacific Time) on October 2, 2023, and, in the case of a proxy access nomination, no earlier than September 2, 2023, and must satisfy the requirements of Rule 14a-8 and our Bylaws, as applicable. The submission of a stockholder proposal or proxy access nomination does not guarantee that it will be included in our proxy materials.

Additionally, our Bylaws provide for advance notice procedures to ~~recommend~~nominate a person for ~~nomination as a~~ director (other than pursuant to our Bylaws’ proxy access provisions) or to propose business to be considered by stockholders at a ~~meeting.~~meeting (other than pursuant to Rule 14a-8). To be considered timely under these provisions, the stockholder’s notice must be received by the Corporate Secretary at our principal executive offices at the address set forth ~~above~~on the first page of this Proxy Statement between 90November 17, 2023 and ~~120 days prior to theone-year~~ ~~anniversary~~our close of ~~the date of the 2020 Annual Meeting;~~business (5:00 p.m. Pacific Time) on December 17, 2023; provided, however, that if the ~~2021~~2024 Annual Meeting date is advanced by more than 30 days before or delayed by more than 60 days after the anniversary date of the ~~2020~~2023 Annual Meeting, then stockholders must provide notice within time periods specified in our Bylaws. Our Bylaws also specify requirements as to the form and content of a stockholder’s notice.

If a stockholder fails to meet these deadlines and fails to satisfy the requirements of Rule 14a-4 under the Exchange Act, we may exercise discretionary voting authority under proxies we solicit to vote on any such proposal as we determine appropriate.

We reserve the right to reject, rule out of order, or take other appropriate action with respect to any nomination or proposal that does not comply with these and other applicable requirements.


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2023 PROXY STATEMENT Proposal One — Election of Directors

Proposal One — Election of Directors

The Company’s Board of Directors (the “Board”) has nominated the following ~~six~~eight persons as directors to serve until the ~~2021~~2024 Annual Meeting or until their successors have been duly ~~elected and qualified.~~elected. Each of the nominees is currently a director of ~~Arrowhead. Except as set forth in~~Arrowhead and was elected most recently by stockholders at the ~~biographical information below, none~~2022 Annual Meeting, except for Ms. Vakiener, who was appointed to the Board on May 2, 2022. Ms. Vakiener was initially recommended to the Nomination Committee by one of the Company’s non-executive officers.

None of the nominees is related by blood, marriage or adoption to any other nominee or any executive officer of the Company. The ~~six~~ nominees receiving ~~the greatest numbers of~~more “FOR” votes than “AGAINST” votes at the Annual Meeting will be elected to the ~~six~~eight director positions. Unless otherwise instructed, the proxy holders will vote the proxies received by them for the ~~six~~eight nominees named below. IfUnder Delaware law, a director not receiving a majority of votes cast in an uncontested election would continue to serve as a director as a “holdover director” until the director resigns or is replaced. Under the Company’s director resignation policy, a director who is not reelected by a majority of the votes cast in an uncontested election will be required to tender his or her resignation to the Board, and the Board will then decide whether to accept or reject the resignation, or whether other action is required. Although we have no reason to believe this will occur, if any nominee is unable or declines to serve as director at the time of the Annual Meeting, the proxies will be voted for any nominee who is designated by our present Board to fill the ~~vacancy.~~vacancy or, alternatively, the Board may reduce its size. The table below sets forth, with respect to each nominee for election, the nominee’s age and current position with Arrowhead.

The director nominees have indicated that they are willing and able to serve as directors. However, if any of the director nominees becomes unable or, for good cause, unwilling to serve, proxies may be voted for the election of such other person as shall be designated by our Board, or the Board may decrease the size of the Board.

Nominees for Election as Directors. The Board unanimously adopted a resolution proposing the nominees set forth below for election as ~~directors~~Directors of the Company for the next year.

OUR BOARD UNANIMOUSLY RECOMMENDS A VOTE

“FOR” EACH OF THE NOMINEES LISTED BELOW.


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~~2020~~Table of Contents

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4

~~2020 PROXY STATEMENT~~ ~~Proposal One — Election of Directors~~


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2023 PROXY STATEMENT Proposal One — Election of Directors

~~2020~~Table of Contents

2023 PROXY STATEMENT Proposal One — Election of Directors


~~William Waddill~~ *Adeoye Olukotun, MD, MPH* *Independent Director*
Age: 62 78 Director since: ~~2018~~ 2020 Serves on: • ~~Audit~~Science Committee ~~(Chair)~~ (Co-Chair) • ~~Compensation~~Nomination Committee • ~~Nominating Committee~~ Other Public Company Boards: •Tonix Pharmaceuticals Holding Corp.			Experience & Expertise Dr. Olukotun is a Mayo Clinic trained cardiologist who has served as Chief Executive Officer of CR Strategies, LLC, which consults on clinical trial design and FDA strategy for pharmaceutical development, since 2001. Dr. Olukotun currently serves on the board of directors of Tonix Pharmaceuticals Holding Corp. (NASDAQ: TNXP), a clinical-stage biopharmaceuticals company. He served as CEO of Epigen Pharmaceuticals, Inc., a discovery phase biotechnology company, from 2014 to 2017, and Vice Board Chair of CardioVax, Inc., a clinical-stage biopharmaceutical company, from 2012 to 2016. He spent the first 20 years of his career in roles of increasing responsibility in clinical development, including multiple product approvals, at Pfizer, Bristol-Myers Squibb, and Mallinckrodt. He has over 35 years of experience in the pharmaceutical industry and has been instrumental in the approval and success of numerous cardiology and metabolic medicines, including the first daily beta blocker and the first approved ACE inhibitor, among others. Dr. Olukotun received his Medical Doctor degree from the Albert Einstein College of Medicine in New York, and a Masters in Public Health from Harvard University School of Public Health.
			Qualifications Dr. Olukotun’s qualifications to serve on the Board include his extensive background in biopharmaceutical development, particularly in the cardiometabolic field, his scientific and public health expertise, and his board and executive leadership experience.


Victoria Vakiener Independent Director
Age: 59 Director since: 2022 Serves on: •Audit Committee •Nomination Committee Other Public Company Boards: •Chimerix, Inc.			Experience & Expertise Ms. Vakiener currently serves on the board of directors of Chimerix (NASDAQ: CMRX), a clinical-stage biopharmaceutical company. From November 2018 through September 2021, she served as Chief Commercial Officer of Epizyme, Inc., a biopharmaceutical company that was acquired in 2022, where she built the commercial organization and launched TAZVERIK for two indications within six months. Prior to joining Epizyme, Ms. Vakiener was an executive at Johnson & Johnson (NYSE: JNJ) for more than twenty years where she held positions of leadership with increasing responsibility across the company’s pharmaceutical and diagnostics businesses. Ms. Vakiener began her pharmaceutical career at Schering-Plough, where she spent nine years in both scientific and commercial roles. Ms. Vakiener received a BS in Biochemistry from Albright College.
			Qualifications Ms. Vakiener’s qualifications to serve on the Board include her deep commercial experience and expertise, her scientific development experience, and her board and executive leadership experience.


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Board Composition and Nominating Process

The ~~Nominating~~Nomination Committee of the Board annually considers the size, composition and needs of the Board and, as appropriate, recommends the nominees for directors to the Board for approval. The ~~Nominating~~Nomination Committee considers and evaluates suggestions from many sources regarding possible candidates for directors. Below are general criteria for the evaluation of current and proposed directors:

•The highest ethical character and shared values with our Code of Corporate Conduct

•Reputation, both personal and professional, consistent with our image and reputation

•Accomplishment within candidate’s field, with superior credentials and recognition

•Relevant expertise and experience and the ability to offer advice and guidance to the Chief Executive Officer (“~~CEO~~”) based on ~~that~~such expertise and experience

•Independence, without the appearance of any conflict in serving as a ~~director,~~Director, and independence of any particular constituency with the ability to represent all stockholders

•Ability to exercise sound business ~~judgment; and~~

judgment

•Diversity, reflecting differences in skills, regional and industry experience, backgrounds, ages, and other unique characteristics, such as race, gender and ethnicity

~~Additionally, the Nominating~~

The Nomination Committee considers the mix of skills and experience among current and prospective directors with a goal of assembling a Board with complementary skills for the benefit of the Company. Listed below are ~~the relevant skills and attributes present in~~selected key contributions of each current Board member.

The table is not intended to be an exhaustive summary of all the contributions of each Board member.

Expertise

~~Expertise~~

Given

~~Given~~

Perry

~~Perry~~

Anzalone

~~Anzalone~~

De Backer

~~De Backer~~

Ferrari

~~Ferrari~~

Olukotun

Vakiener

Waddill

Biopharma Research

& Development

~~Director Tenure~~

~~Biopharma Research~~

~~& Development~~

Healthcare

~~Healthcare~~

Drug Development

Executive Leadership

Public Company

Governance

Accounting/Audit

~~Venture~~

Capital

Markets

Commercial


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2023 PROXY STATEMENT Proposal One — Election of Directors

Board Diversity Matrix

The Nomination Committee believes that the Board should represent a diverse mix of skills, regional and industry experience, backgrounds, ages, and other unique characteristics, such as race, gender, and ethnicity. In furtherance of this goal, the Committee is committed to actively seeking out highly qualified diverse candidates (including women and minority candidates) to include in the pool from which Board nominees are chosen, referred to by some as the “Rooney Rule.”

Currently, one of the Company’s directors self-identifies as Black and two are women. These are the Board’s three most recent additions, demonstrating the Board’s commitment to diversify as it matures. Provided below is a board diversity matrix chart pursuant to Nasdaq’s Board Diversity Rule.

Board Diversity Matrix (As of January 30, 2023)
  Total Number of Directors #8
   Female Male Non-Binary Did Not Disclose Gender
  Part I: Gender Identity
  Directors 2 6 0 0
  Part II: Demographic Background
  African American or Black 0 1 0 0
  Alaskan Native or Native American 0 0 0 0
  Asian 0 0 0 0
  Hispanic or Latinx 0 0 0 0
  Native Hawaiian or Pacific Islander 0 0 0 0
  White 2 5 0 0
  Two or More Races or Ethnicities 0 0 0 0
  LGBTQ+ 0
  Did Not Disclose Demographic Background 0


						12

Table of Contents

2023 PROXY STATEMENT Proposal One — Election of Directors

Corporate Governance, ~~Policies~~Environmental and ~~Practices~~

Social Commitment

The following is a summary of our corporate governance, environmental, and social commitment policies and practices:

•Separate Chair and CEO:The positions of ~~Chairman of the~~ Board Chair and ~~CEO~~Chief Executive Officer are separated, which allows our ~~CEO~~Chief Executive Officer to focus on strategic planning and execution as well as ourday-to-day business operations, while allowing the ~~Chairman of the~~ Board Chair to lead the Board in its fundamental role of providing advice to and oversight of management. While our Bylaws do not require that our ~~Chairman~~Board Chair and ~~CEO~~Chief Executive Officer positions be separate, our Board believes that having separate positions is the appropriate leadership structure for us at this time and demonstrates our commitment to good corporate governance.

•Majority Independent Board:A majority of the members of the Board are independent directors, as defined by Nasdaq Marketplace Rules. The Board has determined that all of the Company’s directors are independent, except Dr. Anzalone, due to his employment relationship with the Company, and Dr. Given, who is the brother of Bruce Given, the Company’s former Chief Operating ~~Officer.~~Officer, who retired in May 2020. Non-employee directors do not receive consulting or other fees from the Company, other than Board and ~~committee~~Committee compensation.

•Independent Lead Director:The Board has appointed an independent Lead Director. The Lead Director is tasked with assuring that the Board committees and other relevant issues have independent leadership.


					7

~~2020 PROXY STATEMENT~~ •~~Proposal One — Election~~Board Oversight of ~~Directors~~Risk:

The Board has overall responsibility for the oversight of the Company’s risk management process, which is designed to support the achievement of organizational objectives, including strategic objectives, to improve long-term organizational performance and enhance stockholder value. Risk management includes not only understanding company-specific risks and the steps management implements to manage those risks, but also what level of risk is acceptable and appropriate for the Company. Management is responsible for establishing our business strategy, identifying and assessing the related risks and implementing appropriate risk management practices. The Board regularly reviews our business strategy and management’s assessment of the related risk and discusses with management the appropriate level of risk for the Company.

•Code of Conduct: All of the Company’s employees, officers, and directors are subject to the Company’s Code of Business Conduct and Ethics Policy, which is available on the Company’s website at www.arrowheadpharma.com. The ethics policy meets the requirements of Nasdaq Marketplace Rules, as well as the code of ethics requirements of the SEC.

•Independent Committees: The Audit, Compensation, and ~~Nominating~~Nomination Committees consist entirely of independent directors.

•Regularly Held Executive Sessions:The independent directors meet separately in executive session on a regular basis to discuss matters relating to the Company and the Board, without members of the management team present.

•Proxy Access: Stockholders have a proxy access right with market-standard terms (3% for 3 years, up to 20% of the Board).

•Board Oversight of Strategy: The Board reviews at least annually the Company’s business initiatives, capital projects and budget matters.

•Environmental and Social Responsibility Oversight: The Board has designated one if its members, Adeoye Olukotun, with responsibility of ensuring the Company’s environmental and social programs align with the Board’s expectations in these matters.

•Related Party Transaction Oversight:The Audit Committee reviews and approves all disclosable related-party transactions or, if the size and nature of the transaction warrants, a special committee ofnon-related Board members is formed to negotiate and approve the transaction.

•Sustainability: The Company continues to assess its environmental impact and ways in which it can operate more responsibly and sustainably. The Company is in the process of building out two research and development facilities, one in Verona, Wisconsin and the other in San Diego, California. Both research & development facilities are being built to meet LEED certification standards. The Company has contracted with a third party to build a solar power generation plant at our San Diego facility with an expected generating capacity of approximately 1,406kW, which will be comprised of a rooftop system, parking lot solar canopies, and a 1,200 kW battery storage system to supply power to the building.


						13

Table of Contents

2023 PROXY STATEMENT Proposal One — Election of Directors

•The Company has been methodically minimizing its use of paper records in favor of electronic records and has a robust recycling program for paper, batteries, and electronic equipment.

•Human Capital Management: Arrowhead has a vibrant and growing culture and we are committed to the health and welfare of our employees. Our important work developing advanced drugs for patients requires a specialized and dedicated workforce. Arrowhead supports the development of our employees with a generous compensation and benefits package, internal advancement, and individualized development opportunities. We are committed to training young scientists and businesspeople and offer multiple internships and entry level positions each year.

•Workforce Diversity: As of December 31, 2022, women comprise 49% of our employee workforce and 39% of our employee leaders at the level of director or above. People self-identifying as racial and ethnic minorities comprise 30% of our employee workforce and 43% of our employee leaders at the level of director or above. One of our executive officers is a member of the LGBTQ+ community.

•Corporate Responsibility: Arrowhead is also committed to the communities in which we operate. The Company and our employees participate in multiple charitable outreach events each year, and in 2023 expect to establish a scholarship fund intended to foster scientific education for minority students.

Stockholder Communications with Directors

Stockholders who wish to communicate with the Board or any individual director can write to: Patrick O’Brien, Corporate Secretary, Arrowhead Pharmaceuticals, Inc.~~,177~~, 177 E. Colorado, Suite 700, Pasadena, CA 91105. Your letter should indicate that you are an Arrowhead stockholder. Depending on the subject matter, management will:

•Forward the communication to the director or directors to whom it is addressed;

•Forward the communication to the ~~Chairman of the~~ Board Chair, if addressed to the ~~Board;~~board of directors; or

•If not addressed to, or otherwise appropriate for, any director or directors, attempt to handle the inquiry directly (for example, requests for information or stock-related matters).

Board Meetings and Committees

The Board held a total of ~~four~~six meetings during the fiscal year ended September 30, ~~2019.~~2022. The Board has three standing committees: Audit Committee, Compensation Committee, and ~~Nominating~~Nomination Committee.

The functions of the Audit Committee are to select and oversee the independent registered public ~~accountants,~~accounting firm, to review the scope and results of theyear-end audit with management and the independent auditors, to review the Company’s accounting principles and its system of internal accounting controls, to review the Company’s annual and quarterly reports before filing with the ~~Securities and Exchange Commission (“~~SEC”) and to review any related-party transactions. The Audit Committee met ~~four~~five times during fiscal ~~2019.~~2022. The members of the Audit Committee for fiscal 2022 were William Waddill (Committee Chair), Marianne De Backer, Adeoye Olukotun, and Michael Perry. The current members of the Audit Committee for fiscal 2023 are William Waddill ~~Chairman,~~(Committee Chair), Marianne De Backer, Mauro Ferrari, and ~~Michael S. Perry.~~Victoria Vakiener. The Board has determined that all members of the Audit Committee who served during ~~2019~~2022 were independent directors under the rules of the Securities and Exchange Commission (“SEC”) and the listing standards of Nasdaq Marketplace Rules and are financially literate. The Board has determined that Mr. Waddill is an “audit committee financial expert” in accordance with the applicable regulations, based on his experience as noted above. The Audit Committee Charter is available on the Company’s website at www.arrowheadpharma.com.

The functions of the Compensation Committee are to review the goals and achievements of the Company and the Chief Executive Officer for the prior year and approve the goals of the Company and the Chief Executive Officer for the next year, to review and approve salaries, bonuses, equity awards, and other benefits payable to the Company’s executive officers and to administer the Company’s ~~2004 Equity Incentive Plan and 2013 Incentive Plan.~~equity incentive compensation plans. The Compensation Committee is specifically responsible for determining the compensation of the Chief Executive Officer and the other executive officers. The Compensation Committee reviews compensation recommendations made by the Chief Executive Officer for other senior executives of the Company and the compensation of the Chief Executive Officer at least annually; the Chief Executive Officer is not present during discussions or deliberations regarding his compensation. In fiscal ~~2019,~~2022, the Compensation Committee engaged Compensia, Inc. (“Compensia”), a national compensation consulting firm, to provide advice and guidance with regard to compensation for our ~~named executive officers.~~NEOs. The decision to engage the consultant was not made or recommended by management and the Compensation Committee has the sole discretion to engage or change the consultant. The Compensation Committee met


8

~~2020 PROXY STATEMENT~~ ~~Proposal One — Election of Directors~~

~~three~~ four times during fiscal ~~2019.~~2022. The members of the Compensation Committee for fiscal 2022 were William Waddill (Committee Chair), Marianne De Backer, Mauro Ferrari, Adeoye Olukotun, and Michael Perry. The current members of the Compensation Committee for fiscal 2023 are ~~Michael S. Perry, Chairman, Mauro Ferrari,~~ William Waddill ~~and~~(Committee Chair), Marianne De ~~Backer.~~Backer, and Michael Perry. The Board has determined that all members of the Compensation Committee are independent directors under


						14

Table of Contents

2023 PROXY STATEMENT Proposal One — Election of Directors

the listing rules of Nasdaq Marketplace Rules. The Compensation Committee’s charter is available on the Company’s website at www.arrowheadpharma.com. The Compensation Committee has not delegated any of its responsibilities or authorities granted under its charter.

The ~~Nominating~~Nomination Committee is responsible for proposing a slate of directors for election by the stockholders at each ~~Annual Stockholders Meeting~~annual meeting and for proposing candidates to fill any vacancies. The ~~Nominating~~Nomination Committee met ~~once~~three times during fiscal ~~2019.~~2022.The members of the Nomination Committee for fiscal 2022 were Marianne De Backer (Committee Chair), Mauro Ferrari, Adeoye Olukotun, and Michael Perry. The current members of the ~~Nominating~~Nomination Committee for fiscal 2023 are ~~Michael S. Perry, Chairman,~~ Marianne De Backer (Committee Chair), Mauro Ferrari, Adeoye Olukotun, Michael Perry, Victoria Vakiener, and William Waddill. The ~~Nominating~~Nomination Committee’s charter is available on the Company’s website at www.arrowheadpharma.com. The ~~Nominating~~Nomination Committee manages the process for evaluating current Board members at the time they are considered forre-nomination. After considering the appropriate skills and characteristics required on the Board, the current makeup of the Board, the results of the evaluations and the wishes of the Board members to bere-nominated, the ~~Nominating~~Nomination Committee recommends to the Board whether those individuals should bere-nominated.

On at least an annual basis, the ~~Nominating~~Nomination Committee reviews with the Board whether it believes the Board would benefit from adding new members and, if so, the appropriate skills and characteristics required for any new members. If the Board determines that a new member would be beneficial, the ~~Nominating~~Nomination Committee solicits and receives recommendations for candidates and manages the process for evaluating candidates. All potential candidates, regardless of their source, are reviewed under the same process. The ~~Nominating~~Nomination Committee (or ~~its chairman)~~the Committee Chair) screens the available information about the potential candidate(s). Based on the results of the initial screening, interviews with candidates are scheduled with ~~Nominating~~Nomination Committee members, other members of the Board and senior members of management. Upon completion of these interviews and other due diligence, the ~~Nominating~~Nomination Committee may ~~nominate~~recommend a candidate to the Board for ~~election.~~

appointment.

Candidates for independent Board member positions are identified through recommendations from directors or others associated with the Company, as well as through a formal search process managed by ~~an executive recruiter.~~a third-party search firm. Arrowhead stockholders may also recommend candidates by sending the candidate’s name and resume to the ~~Nominating~~Nomination Committee pursuant to the procedures, set forth above, for communication with the Board. As described above, our Bylaws also provide for separate notice procedures to recommend a person for nomination as a director to be considered by stockholders at a meeting, including requirements as to the timing, form and content of a stockholder’s notice.

The ~~Nominating~~Nomination Committee has no predefined minimum criteria for selecting Board nominees, although it believes that all directors should share qualities such as governance and business experience at the corporate level, relevantnon-competitive experience, and strong communication and analytical skills. Independent directors must meet the criteria for independence set forth by Nasdaq and, as applicable, the SEC. In any given search, the ~~Nominating~~Nomination Committee may also define particular characteristics for candidates to balance the overall mix of skills, backgrounds and characteristics of the Board and the needs of the Company. During any search, the ~~Nominating~~Nomination Committee reserves the right to modify its stated search criteria for exceptional candidates.

~~As part of the Nominating Committee’s~~

The Nomination Committee assesses its effectiveness in achieving its goal of building a diverse board the Nominating Committee is committed to actively seeking out highly qualified diverse candidates (including women and minority candidates) to include in the pool from which Board nominees are chosen. The Nominating Committee assesses its effectiveness in achieving this goal as part of its annual assessment of the composition of the Board.

In 2018, the Board established ~~an ad hoc~~a Science Committee to review and advise on science topics of interest to the Company. The members of the Science Committee for fiscal 2022 were Mauro Ferrari (Committee Co-Chair), Adeoye Olukotun (Committee Co-Chair), Marianne De Backer, and Douglass Given. The current members of the ~~committee~~Science Committee for fiscal 2023 are Mauro Ferrari ~~Chairman,~~(Committee Co-Chair), Adeoye Olukotun (Committee Co-Chair), Douglass Given, and Michael S. Perry.

Each of our incumbent ~~director~~directors attended ~~fewer than~~at least 75% of the aggregate of (i) the total number of meetings of the Board held during fiscal ~~2019,~~2022, and (ii) the total number of meetings held by all committees of the Board during fiscal ~~2019~~2022 on which such person ~~served.~~

served, in each case during the period in which such person served on the Board or committee.

In addition, all of the directors then serving on the Board attended the virtual ~~2019~~2022 Annual Meeting of Stockholders. It is the Company’s policy to encourage, but not require, that all directors attend our annual stockholder meetings.

~~2020 PROXY STATEMENT~~

Director Compensation

~~Director Compensation~~

Directors who are also employees of the Company receive no separate compensation from the Company for their service as members of the Board. For ~~2020,~~2022, the Company maintained the structure of director compensation ~~that was~~it adopted in 2019 to provide a base retainer for each director with higher base retainers for service by the ~~Chairman of the~~ Board Chair and the Lead Independent Director. The Company provides an additional ~~retainers~~retainer for committee leadership of the Audit Committee and Compensation Committee. The average total compensation paid to the Company's non-executive directors for service ~~with higher retainers for committee leadership.~~in 2022 is at or below the 60th percentile of the total compensation paid to non-executive directors of its peer group as described later in this proxy statement. The Compensation Committee believes the structure aligns compensation according to ~~specific leadership and committee~~the level of service contributions by each director. ~~Year over year, total director compensation increased modestly in 2020 to reflect the increased demands and complexity as the Company adds to and advances our pipeline.~~

~~The below table sets forth compensation levels for each of our outside directors for calendar 2019 and 2020.~~

Name & Position
2020 Annual
Fee (1)
(effective
1/1/20)
   2020 Stock
Award (2)    2020 Grant
Date Value    2019 Annual
Fee (3)
(effective
1/1/19)    2019 Stock
Award (2)
2019 Grant
Date Value

  Douglass Given
  Chairman

   $

85,000



8,000

   $

507,440

   $

80,000



36,000

   $

447,120

  Michael S. Perry
  Lead Director

   $

80,000



8,000

   $

507,440

   $

80,000



36,000

   $

447,120

  Mauro Ferrari
  Director (4)

   $

120,000



7,500

   $

475,725

   $

135,556



8,429

   $

194,738

  William Waddill
  Director

   $

75,000



7,500

   $

475,725

   $

70,000



30,000

   $

372,600

  Marianne De Backer
  Director (5)

   $

70,000



7,500

   $

475,725

   $

0



5,000

   $

336,600

~~(1)~~

~~The annual fee for 2020 service is summarized as follows:~~

~~Dr. Given will receive $80,000 for his service as the Chairman of the Board and $5,000 for his service on the Science Committee.~~

Dr. Perry will receive $50,000 for his service as the Lead Director, $15,000 for his service as the Compensation Committee Chairman, $5,000 for his service as the Nominating Committee Chairman, and a total of $10,000 for his service on the Audit and Science Committees.

Dr. Ferrari will receive $45,000 for his service as a Company director, $15,000 for his service as the Science Committee Chairman, a total of $10,000 for his service on the Nominating and Compensation Committees, and $50,000 for his service on a special board project.

Mr. Waddill will receive $45,000 for his service as a Company director, $20,000 for his service as the Audit Committee Chairman, and a total of $10,000 for his service on the Nominating and Compensation Committees.

~~Dr. De Backer will receive $45,000 for her service as a Company director, a total of $15,000 for her service on the Audit, Compensation and Nominating Committees, and a $10,000 sign on bonus.~~

~~(2)~~

~~For services in 2020, eachnon-employee~~ ~~director received a grant of 7,500 restricted stock units (“RSUs”). Additional grants of 500 RSUs were awarded for the service of the Chairman and the Lead Director. RSU grants tonon-employee~~ ~~directors vest on theone-year~~ ~~anniversary of the date of grant. In 2019, the grant for each director was 30,000 RSUs with additional grants of 6,000 RSUs for the service of the Chairman and the Lead Director.~~

~~(3)~~

~~The annual fee for 2019 service is summarized as follows:~~

~~Dr. Given received $75,000 for his service as the Chairman of the Board, and $5,000 for his service on the Board’s Science Committee.~~

Dr. Perry received $50,000 for his service as the Lead Director, $15,000 for his service as the Compensation Committee Chairman and a total of $15,000 for his service on the Nominating, Science and Audit Committees.

Dr. Ferrari received $40,000 for his service as a Company director, $10,000 for his service as the Science Committee Chairman, $15,000 for his service on the Nominating, Audit and Compensation Committees and $70,556 for his service on a special board project that was initiated in April 2019.

Mr. Waddill received $40,000 for his service as a Company director, $20,000 for his service as the Audit Committee Chairman, and a total of $10,000 for his service on the Nominating and Compensation Committees.

~~(4)~~

~~In 2019, Dr. Ferrari’s stock awards were lower than the other directors because his compensation had historically been limited based on the policies of his employer.~~

~~(5)~~

~~Dr. De Backer joined the board in December 2019, and as such, she did not receive an annual cash fee in 2019. Dr. De Backer was awarded a grant of 5,000 RSUs in December 2019 as asign-on~~ ~~award.~~


10

~~2020 PROXY STATEMENT~~ ~~Director Compensation~~

The following table sets forth the total compensation paid to ournon-employee directors in fiscal ~~2019.~~2022. Dr. Anzalone’s compensation is set forth in the discussion of Executive Compensation and in the Summary Compensation Table.

Name


Fee Earned
or
Paid in Cash
($)


Stock
Awards ($)
(1) (2)


Total ($)

  Douglass Given

   $

78,438

   $

447,120

   $

525,558

  Michael S. Perry

   $

75,813

   $

447,120

   $

522,933

  Mauro Ferrari (3)

   $

107,431

   $

194,738

   $

302,169

  William Waddill

   $

64,375

   $

372,600

   $

436,975

  Marianne De Backer (4)



N/A



N/A



N/A

~~(1)~~

~~This column represents the total grant date fair value, computed in accordance with ASC 718, of restricted stock units granted during fiscal year 2019 for each director.~~

~~(2)~~

~~The RSUs granted tonon-employee~~ ~~directors vest one year from the date of grant. RSUs granted to Dr. Ferrari vested as discussed in footnote 3 below.~~

~~(3)~~

Dr. Ferrari’s fees earned in cash include his annual fees of $61,875 and cash compensation relating to a special board project of $45,556. Dr. Ferrari’s stock awards include an award of 3,429 shares of common stock on 1/1/19, valued at $44,988. This award vested immediately because Dr. Ferrari’s compensation had historically been limited based on the policies of his employer. Additionally, Dr. Ferrari received an award of 5,000 RSUs in September 2019, valued at $149,750, that vested on January 1, 2020. This award was granted to Dr. Ferrari as additional compensation relating to the special board project previously discussed.

~~(4)~~

~~Dr. De Backer joined the board in December 2019, and as such, fiscal year 2019 fees and stock awards were not applicable.~~


Name	Fee Earned or Paid in Cash ($)	Stock Awards ($) (1) (2)	Total ($)
Douglass Given	$95,000	$377,280	$472,280
Michael S. Perry	$80,000	$377,280	$457,280
Mauro Ferrari	$80,000	$377,280	$457,280
William Waddill	$90,000	$377,280	$467,280
Marianne De Backer	$80,000	$377,280	$457,280
Adeoye Olukotun	$80,000	$377,280	$457,280
Victoria Vakiener	$25,000	$633,793	$658,793

(1)This column represents the total grant date fair value, computed in accordance with ASC 718, of restricted stock units granted during fiscal year 2022 to each director.

(2)The RSUs granted to non-employee directors vest one year from the date of grant, subject to continued service through the vesting date.

As of the last day of fiscal year ~~2019,~~2022, the directors held the following outstanding ~~stock option and~~ restricted stock unit grants in the aggregate: Douglass Given — ~~36,000 restricted stock units;~~6,400; Michael S. Perry — ~~77,000 stock options and 36,000 restricted stock units;~~6,400; Mauro Ferrari — ~~20,000 stock options and 5,000 restricted stock units; and~~6,400; William Waddill — ~~30,000~~6,400; Marianne De Backer — 6,400; Adeoye Olukoton — 6,400; and Victoria Vakiener — 15,417 restricted stock units.

Vote Required; Recommendation of the Board

The ~~six~~ nominees listed above receiving ~~the greatest numbers of~~more “FOR” votes ~~at the meeting,~~than “AGAINST” votes, assuming a quorum is present, will be elected ~~to the six director positions~~as directors to serve until their terms expire or until their successors have been duly elected and qualified. Because directors are elected by ~~plurality,~~a majority of votes cast, abstentions from voting and brokernon-votes, if any, will be ~~entirely~~ excluded from the vote and will have no effect on its outcome.

THE BOARD UNANIMOUSLY RECOMMENDS A VOTE

“FOR” EACH OF THE NOMINEES FOR DIRECTOR IN PROPOSAL ONE.

~~2020~~Table of Contents

2022 PROXY STATEMENT Proposal Two — Advisory Vote to Approve Executive Compensation

Proposal Two — Advisory Vote to Approve Executive Compensation

The compensation paid to our Named Executive Officers (“NEOs”) is described below in the Compensation Discussion and Analysis of this proxy statement for the year ended September 30, ~~2019.~~2022. The Board is asking stockholders to cast anon-binding, advisory vote FOR the following resolution:

“RESOLVED, that the compensation paid to the Company’s named executive officers, as disclosed pursuant to Item 402 of RegulationS-K, as set forth in the compensation tables and narrative discussion, is hereby APPROVED.”

Although the vote we are asking you to cast isnon-binding, the Compensation Committee and the Board value the views of our stockholders and will consider the outcome of the vote when determining future compensation arrangements for our ~~named executive officers.~~

NEOs.

The Board has adopted a policy providing for annual advisory votes to approve executive compensation. Unless the Board modifies its policy on the frequency of holding advisory votes to approve executive compensation, the next such advisory vote will occur in ~~2021.~~

2024.

Vote Required; Recommendation of the Board

Proposal Two must be approved by the Required Vote, assuming a quorum is present. For this purpose, abstentions will be counted as a vote ~~against~~“AGAINST” the proposal, while brokernon-votes, if any, will have no effect on the outcome of the vote.

THE BOARD UNANIMOUSLY RECOMMENDS A VOTE

“FOR” PROPOSAL TWO.


12

~~2020 PROXY STATEMENT~~ ~~Proposal Three — Amendment to Bylaws to Elect Directors by a Majority Vote~~

~~Proposal Three — Amendment to Bylaws to Elect Directors by a Majority Vote~~

In Proposal 3, we are asking stockholders to approve an amendment and restatement of our current Bylaws to implement a majority voting standard for the election of directors in uncontested elections. Our current Bylaws provide for a plurality voting standing, pursuant to which the director nominees who receive a plurality of votes in an election for directors are elected whether or not they receive a majority of the votes cast. In response to suggestions by our stockholders in fiscal year 2019, the Board has determined it is in the best interests of the Company and stockholders and has adopted, subject to stockholder approval, an amendment and restatement of our Bylaws to provide that in an uncontested election of directors, each director must receive more “For” votes than “Withheld” votes to be elected. In any contested elections of directors, where there are two or more nominees for a board position, the election will continue to be decided by plurality vote.

Under existing Delaware law, a director not receiving a majority of votes in an uncontested election would continue to serve as a director as a “holdover director” until the director resigns or is replaced. The amendment and restatement also provides for a director resignation policy under which a director who is not reelected by a majority of the votes cast in an uncontested election will be required to tender his or her resignation to the Board, and the Board will then decide whether to accept or reject the resignation, or whether other action is required. Under the policy, a director who is proposed for reelection and who does not receive a majority of the votes cast will not automatically remain on the Board as a holdover director. Rather, his or her continued service as a director will be subject to review by the Board, taking into account the stockholders’ vote and any other relevant considerations.

The foregoing is a summary of the proposed amendment of our Bylaws, which is qualified in its entirety by reference to the full text of the Amended and Restated Bylaws as set forth in Exhibit A (with additions shown as underlined and deletions shown as struck through).

~~The Board is asking stockholders to cast a vote FOR the following resolution:~~

~~“RESOLVED, that the stockholders of the Company approve the Amended and Restated Bylaws in a form substantially as provided in Exhibit A to this Proxy Statement.”~~

~~THE BOARD UNANIMOUSLY RECOMMENDS A VOTE~~

~~“FOR”~~ ~~PROPOSAL 3~~

~~2020~~Table of Contents

2023 PROXY STATEMENT Executive Compensation

Executive Compensation

COMPENSATION DISCUSSION AND ANALYSIS

The following compensation discussion and analysis contains statements regarding future individual and Company performance targets and goals. These targets and goals are disclosed in the limited context of Arrowhead’s executive compensation ~~programs~~program and should not be understood to be statements of management’s expectations or guidance. Arrowhead cautions investors not to apply these statements to other contexts. Fiscal years are denoted as fiscal years, all other year references refer to calendar years.

This Compensation Discussion and Analysis describes the compensation program for our ~~Named Executive Officers.~~NEOs. During fiscal ~~year 2019,~~2022, these individuals were:

•Christopher Anzalone, our President and ~~CEO;~~

~~Bruce D. Given, our~~ Chief ~~Operating~~Executive Officer (our “~~COO~~CEO”);

•Kenneth Myszkowski, our Chief Financial Officer (our “CFO”);

•James Hamilton, our Chief of Discovery and Translational Medicine (our “CDTM”);

•Patrick O’Brien, our Chief Operating Officer and General Counsel (our “COO”and“GC”); and

~~Zhen Li,~~•Tracie Oliver, our ~~former Senior Vice President, Chemistry &Non-Clinical~~ ~~Development~~Chief Commercial Officer (our “~~SVP~~CCO”).

This Compensation Discussion and Analysis describes the material elements of our executive compensation program during ~~2019.~~fiscal 2022. It also provides an overview of our executive compensation philosophy and objectives and summarizes our executive compensation policies and practices. Finally, it analyzes how and why the Compensation Committee of our Board arrived at the specific compensation decisions for our executive officers, including our ~~Named Executive Officers~~NEOs, for ~~2019~~fiscal 2022 including the key factors that the Compensation Committee considered in determining their compensation.

Our Company

We develop medicines that treat intractable diseases by silencing the genes that cause them. Using a broad portfolio of RNA chemistries and efficient modes of delivery, our therapies trigger the RNA interference mechanism to induce rapid, deep and durable knockdown of target genes. RNA interference, or RNAi, is a mechanism present in living cells that inhibits the expression of a specific gene, thereby affecting the production of a specific protein. Arrowhead’s RNAi-based therapeutics leverage this natural pathway of gene silencing.

Arrowhead is focused on developing innovative drugs for diseases with a genetic basis, typically characterized by the overproduction of one or more proteins. The depth and versatility of our RNAi technologies enable us to potentially address conditions in virtually any therapeutic area and pursue disease targets that are not otherwise addressable by small molecules and biologics.

~~2019~~

2022 Business Highlights

~~Began dosing~~

•Dosed the first patients in its PALISADE study, a Phase ~~1 single~~3 clinical study to evaluate the safety and ~~multiple dose~~efficacy of ARO-APOC3 in adults with familial chylomicronemia syndrome (FCS);

•Filed for regulatory clearance to begin a Phase 1/2a study of~~ARO-ANG3,~~ ARO-C3 and subsequently dosed the first subjects in AROC3-1001, a ~~subcutaneously administered RNAi~~Phase 1/2 clinical study of ARO-C3, the Company’s investigational RNA interference (RNAi) therapeutic ~~targeting angiopoietin like protein~~designed to reduce production of complement component 3 ~~being developed~~(C3) as a potential ~~treatment~~therapy for various complement mediated diseases;

•Presented additional interim clinical data from AROHSD-1001, AROAAT-2002, and AROAPOC3-1001;

•Completed enrollment in Phase 2b ARCHES-2 study of investigational ARO-ANG3 for patients with ~~dyslipidemias~~mixed dyslipidemia;

•Filed for regulatory clearance to initiate Phase 1/2a study of ARO-RAGE and ~~metabolic diseases;~~

~~Began dosing in a Phase 1 single and multiple dose study ofARO-APOC3,~~ ~~a subcutaneously administered RNAi therapeutic targeting apolipoproteinC-III,~~ ~~being developed as a potential~~subsequently dosed first subjects for treatment ~~for patients with hypertriglyceridemia;~~

of Asthma;

~~Expanded the AROHBV1001 Phase 1/2 study to include a new triple combination cohort (cohort 12) that includesJNJ-3989~~ ~~and additional undisclosed agents selected by Arrowhead’s partner, Janssen Pharmaceuticals, Inc.;~~

~~Began dosing patients in an adaptive design Phase 2/3 trial, called SEQUOIA, with the potential to serve as a pivotal registrational study ofARO-AAT,~~ ~~Arrowhead’s second generation subcutaneously administered RNAi therapeutic being developed as a treatment for a rare genetic liver disease associated withalpha-1~~ ~~antitrypsin deficiency;~~

~~Presented new clinical data on our two cardiometabolic candidates,ARO-APOC3~~ ~~andARO-ANG3,~~ ~~in two late-breaking oral presentations at the American Heart Association Scientific Sessions 2019);~~


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~~In April 2019,~~•Filed for regulatory clearance to initiate Phase 1/2a study of ARO-MUC5AC and subsequently dosed first subjects for treatment of muco-obstructive lung disease;

•Filed for regulatory clearance to initiate Phase 1/2a study of ARO-MMP7 for treatment of idiopathic pulmonary fibrosis (IPF);

•Initiated and dosed the first patients in the Phase 2 GATEWAY clinical study of investigational ARO-ANG3 for the treatment of patients with homozygous familial hypercholersterolemia;

•Entered into definitive agreements to form a joint venture, Visirna Therapeutics, Inc., with Vivo Capital through which the Company ~~earned~~and Vivo Capital intend to expand the reach of innovative medicines in Greater China;

•Hosted a ~~$25 million milestone payment~~pulmonary research & development (R&D) day to discuss the Company’s emerging pipeline of pulmonary targeted RNA interference (RNAi) therapeutic candidates that leverage its proprietary Targeted RNAi Molecule (TRiMTM) platform, including an announcement of its previously undisclosed candidate designed to reduce expression of matrix metalloproteinase 7 (MMP7) as a potential treatment for idiopathic pulmonary fibrosis (IPF);

•Entered into an exclusive license agreement with GSK for ARO-HSD;

•Janssen presented clinical data from ~~Janssen following~~REEF-1, a Phase 2b study of different combination regimens, including JNJ-73763989 (JNJ-3989), formerly called ARO-HBV, and/or JNJ-56136379 (JNJ-6379), and a nucleos(t)ide analog (NA) for the ~~initiation~~treatment of ~~dosing~~chronic hepatitis B virus infection (CHB);

•In conjunction with Takeda, announced results from a Phase 2 clinical study (AROAAT-2002) of investigational fazirsiran (TAK-999/ARO-AAT) for the treatment of liver disease associated with alpha-1 antitrypsin deficiency (AATD), and was recently published in the ~~triple combination cohort (cohort 12)~~New England Journal of Medicine (NEJM) and presented in an oral presentation at The International Liver Congress™ 2022 - The Annual Meeting of the European Association for the Study of the Liver (EASL); and

•Completed the purchase of 13 acres of land in the ~~Company’s ongoing Phase 1 / 2 study~~Verona Technology Park in Verona, Wisconsin and held a groundbreaking ceremony on the site. As part of~~JNJ-3989(ARO-HBV).~~ ~~In August 2019,~~ this acquisition, the Company ~~earned an additional $25 million milestone payment from Janssen following the initiation of dosing in its phase 2b study ofJNJ-3989(ARO-HBV);~~

~~In December 2019, the Company closed an underwritten public offering and received gross proceeds of $266.8 million, before deducting underwriting discounts, commissions and other offering expenses;~~

~~Ended calendar 2019 with $528 million in cash and investments; and~~

~~Achieved 47% total stockholder return (“~~~~TSR~~~~”) in fiscal 2019.~~

~~Business Development~~

~~Janssen Pharmaceuticals, Inc.~~

~~In October 2018, we~~ entered into a development agreement with the City of Verona to construct certain infrastructure improvements within the tax incremental district and expects to be reimbursed up to $16.0 million by the City of Verona by future tax increment revenue generated from the developed property. The site is being developed into an approximately 160,000 square foot drug manufacturing facility and an approximately 140,000 square foot laboratory and office facility which will support the Company’s process development and analytical activities and is expected to be complete in late 2023 or early 2024. Additionally, the Company entered into a lease agreement for a new 144,000 square foot laboratory and office facility in San Diego, California to support discovery activities, which it currently anticipates to be available in April 2023.

Business Development

GlaxoSmithKline Intellectual Property (No. 3) Limited (“GSK”)

In November 2021, the Company entered into an exclusive license agreement with ~~Janssen Pharmaceuticals, Inc., part of the Janssen Pharmaceutical Companies of Johnson & Johnson,~~GSK to develop and commercialize~~ARO-HBV.~~ ~~In addition, we entered into~~ ARO-HSD, a ~~research collaboration~~Phase 2 investigational therapy in development to treat NASH. The exclusive license is worldwide with the exception of greater China, for which the Company retained rights to develop and ~~option agreement with Janssen to potentially collaborate~~commercialize ARO-HSD.

The Company has completed its Phase 1/2 study of ARO-HSD, and GSK is now wholly responsible for ~~up to three additional RNAi therapeutics against new targets to be selected by Janssen.~~

all clinical development and commercialization of ARO-HSD in its territory. Under the terms of the ~~license~~ agreement, wethe Company has received ~~$175 million as~~ an upfront ~~payment. Separately, Johnson & Johnson Innovation — JJDC, Inc. (JJDC) made~~payment of $120 million and is eligible for additional payments of $30 million at the start of Phase 2 and $100 million upon achieving a ~~$75 million equity investment~~successful Phase 2 trial readout and the first patient dosed in ~~Arrowhead at~~ a ~~price of $23.00 per share of Arrowhead common stock. As discussed above,~~Phase 3 trial. Furthermore, should the Phase 3 trial read out positively, and the potential new medicine receives regulatory approval in ~~April 2019,~~major markets, the deal provides for commercial milestone payments to the Company ~~earned a $25 million milestone payment from Janssen following the initiation~~ of ~~dosing in the triple combination cohort (cohort 12) in the Company’s ongoing Phase 1 / 2 study ofJNJ-3989(ARO-HBV)~~ ~~and an additional $25 million milestone payment from Janssen following the initiation of dosing in its phase 2b study ofJNJ-3989(ARO-HBV).~~

~~In addition, Arrowhead is eligible to receive~~ up to ~~approximately $1.6 billion in milestone payments under the license agreement. Arrowhead is also eligible to receive approximately $1.9 billion in option~~$190 million at first commercial sale, and ~~milestone payments under the collaboration and option agreement related to~~ up to ~~three additional targets. Arrowhead~~$590 million in sales-related milestone payments. The Company is further eligible to receive tiered royalties on net product sales in a range of mid-teens to twenty percent.

Visirna Therapeutics, Inc. (“Visirna”)

On April 25, 2022, Visirna and the Company entered into a License Agreement (the “Visirna License Agreement”), pursuant to which Visirna received an exclusive license to develop, manufacture and commercialize four of the Company’s RNAi-based investigational cardiometabolic medicines in Greater China (including the People’s Republic of China, Hong Kong, Macau and Taiwan). Pursuant to a Share Purchase Agreement entered into simultaneously


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with the Visirna License Agreement (the “Visirna SPA”), the Company acquired a majority stake in Visirna (after accounting for shares reserved for Visirna’s employee stock ownership plan) as partial consideration for the Visirna License Agreement. Under the Visirna SPA, entities affiliated with Vivo Capital also acquired a minority stake in Visirna in exchange for $60 million in cash to support the operations of Visirna. As further consideration under the Visirna License Agreement, the Company is also eligible to receive potential royalties on commercial sales.

Royalty Pharma Investments 2019 ICAV (“Royalty Pharma”)

On November 9, 2022, the Company and Royalty Pharma entered into an agreement, pursuant to which Royalty Pharma agreed to pay up to ~~mid teens~~$410.0 million in cash to the Company in consideration for the Company’s future royalty interest in Olpasiran, a small interfering RNA (siRNA) originally developed by the Company and licensed to Amgen in 2016 under the ~~license agreement~~Olpasiran Agreement. Pursuant to the Royalty Pharma Agreement, Royalty Pharma paid $250 million upfront on November 9, 2022. The Company will retain rights to the $400 million in development, regulatory, and ~~up to low teens under the collaboration and option agreement on product sales.~~

sales milestone payments potentially due from Amgen.

Platform

In fiscal ~~2019, Janssen selected its first of potentially three RNAi therapeutics under our 2018 collaboration agreement,ARO-JNJ1,~~ ~~against an undisclosed target.~~

~~Platform~~

~~In 2019, we~~2022, the Company continued to develop and deploy our Targeted RNAi Molecule platform or (“TRiM™,) to identify and develop new ~~therapeutics, including~~therapeutics. TRiM~~ARO-HIF2,ARO-HSD,~~™ ~~andARO-ENaC~~ ~~. TRiM~~^™ utilizes ligand-mediated delivery and is designed to enable tissue-specific targeting, while being structurally simple. The TRiM™ platform is designed to offer several potential competitive advantages including:

•A more sophisticated RNAi trigger selection and screening process that identifies potent sequences rapidly in locations that RNAi competitors may miss;

•Multiple routes of administration including subcutaneous, intravenous and inhaled;

•Faster time to clinical candidates;

•Optimal pharmacologic activity and longduration-of-effect;

•Potentially wide safety margins;

•Simplified manufacturing at reduced cost;

and

~~And, the promise of taking~~•The ability to take RNAi to tissues beyond the liver.


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Pipeline

~~We are~~

Arrowhead is focused on developing innovative drugs for diseases with a genetic basis, typically characterized by the overproduction of one or more ~~proteins.~~proteins that are involved with disease. The depth and versatility of ~~our~~Arrowhead's RNAi technologies ~~enable us~~enables Arrowhead to potentially address conditions in virtually any therapeutic area and pursue disease targets that are not otherwise addressable by small molecules and biologics.

Arrowhead is focused on bringing the promise of RNAi to address diseases outside of the liver, and its pipeline now includes disease targets in the liver, lung, muscle and other undisclosed tissue types.

The timing of our planned and already filed clinical trial applications ~~(CTA)~~(“CTA”) discussed below are based on calendar years, not fiscal years.


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~~2020 PROXY STATEMENT~~
~~Executive Compensation~~

Arrowhead Proprietary Clinical Stage Candidates

~~ARO-AAT~~ ~~is a clinical-stage RNAi therapeutic candidate for the treatment of liver disease associated withalpha-1~~ ~~antitrypsin deficiency.ARO-AAT~~ ~~is designed to knock down theAlpha-1~~ ~~antitrypsin (AAT) gene transcript and reduce the hepatic production of the mutant AAT protein.ARO-AAT~~ ~~is a next-generation subcutaneously administered compound that follows a previous generation AAT compoundARC-AAT.~~

~~2017:ARO-AAT~~ ~~nominated; CTA filed~~

•

~~2018: Clinical trial commenced. Initial results from AROAAT1001 were presented in November 2018 at The Liver Meeting~~^®~~, the Annual Meeting of the American Association for the Study of Liver Disease (AASLD). Key data include:~~

~~Three monthly doses of 300 mgARO-AAT~~ ~~led to reductions in serumalpha-1~~ ~~antitrypsin to below the level of quantitation in 100% of subjects.~~

~~Reductions were sustained for greater than 14 weeks indicating that quarterly or less frequent dosing appears feasible.~~

~~Single and multiple doses ofARO-AAT~~ ~~appeared to be well-tolerated at all doses tested.~~

~~2019: One phase 2/3 and one Phase 2 trial were initiated (enrolling concurrently):~~

~~SEQUOIA, a potentially pivotal multi-center, multi-dose, placebo-controlled, adaptive Phase 2/3 study to evaluate the safety, efficacy and tolerability ofARO-AAT,~~ ~~administered subcutaneously to patients withalpha-1~~ ~~antitrypsin deficiency~~

~~AROAAT2002, a pilot open-label, multi-dose, Phase 2 study to assess changes in a novel histological activity scale in response toARO-AAT~~ ~~over time in patients withalpha-1~~ ~~antitrypsin deficiency associated liver disease.~~

ARO-ANG3 is designed to reduce production of angiopoietin-like protein 3 ~~(ANGPTL3)~~(“ANGPTL3”), a liver synthesized inhibitor of lipoprotein lipase and endothelial lipase. ANGPTL3 inhibition has been shown to lower serum LDL, serum and liver triglyceride and has genetic validation as a novel target for cardiovascular disease.

Arrowhead is currently investigating ARO-ANG3 in two Phase 2b clinical trials.

~~2017: Target identified~~

~~2018: Filed~~•Dyslipidemia and Hypertriglyceridemia: Dyslipidemia and hypertriglyceridemia are risk factors for ~~regulatory clearance~~atherosclerotic coronary heart disease and cardiovascular events.

•Study Name: Study of ARO-ANG3 in Adults With Mixed Dyslipidemia (ARCHES-2)
A Double-blind, Placebo-controlled Phase 2b Study to ~~begin a~~ Evaluate the Efficacy and Safety of ARO-ANG3 in Adults With Mixed Dyslipidemia
ClinicalTrials.gov Identifier: NCT04832971

•Study Name: Study of ARO-ANG3 in Participants With Homozygous Familial Hypercholesterolemia (HoFH) (GATEWAY)
Phase ~~1 study.~~

~~2019: Clinical trial commenced. Initial results from AROANG1001 presented at~~2 Study to Evaluate the ~~2019 Global Summit on Cardiology~~Safety and ~~heart Diseases and the November 2019 American Heart Association meeting. Key data include:~~

~~Dose dependent reductions~~Efficacy of ARO-ANG3 in ~~serum ANGPTL3 (mean maximum reduction ranging from 55% in the 35 mg cohort to 83% in the 300 mg cohort), which were maintained through the end of the study.~~

Subjects with Homozygous Familial Hypercholesterolemia (HoFH)
ClinicalTrials.gov Identifier: NCT05217667

~~Dose dependent reduction in triglycerides andVLDL-C~~ ~~(mean maximum triglyceride reduction ranging from 31% in the 35 mg cohort and 66% in the 200 mg cohort and mean maximumVLDL-C~~ ~~ranging from 30% in the 35 mg cohort to 65% in the 200 mg cohort). Reductions in triglycerides andVLDL-C~~ ~~in the 200 mg and 300 mg cohorts were maintained through end of study.~~

ARO-APOC3 is designed to reduce production of Apolipoprotein~~C-III(apoC-III)~~ C-III (apoC-III), a component of triglyceride rich lipoproteins ~~(TRLs)~~(“TRLs”) including VLDL and chylomicrons and a key regulator of triglyceride metabolism. ~~The company~~Arrowhead believes that knocking down the hepatic production ofapoC-III may result in reduced VLDL synthesis and assembly, enhanced breakdown of TRLs and better clearance of VLDL and chylomicron remnants.

Arrowhead is currently investigating ARO-APOC3 in two Phase 2b clinical trials and one Phase 3 clinical trial.

~~2017: Target identified~~

~~2019: Clinical trial commenced. Initial results from AROAPOC31001 presented at~~•Study Name: Study to Evaluate ARO-APOC3 in Adults With Severe Hypertriglyceridemia (SHASTA-2)
A Double-Blind, Placebo-Controlled Phase 2b Study to Evaluate the ~~2019 Global Summit on Cardiology~~Efficacy and ~~heart Diseases~~Safety of ARO-APOC3 in Adults With Severe Hypertriglyceridemia
ClinicalTrials.gov Identifier: NCT04720534

•Study Name: Study of ARO-APOC3 in Adults With Mixed Dyslipidemia (MUIR)
A Double-Blind, Placebo-Controlled Phase 2b Study to Evaluate the Efficacy and Safety of ARO-APOC3 in Adults With Mixed Dyslipidemia
ClinicalTrials.gov Identifier: NCT04998201

•Study Name: Study of ARO-APOC3 in Adults With FCS (PALISADE)
A Phase 3 Study to Evaluate the ~~November 2019 American Heart Association meeting. Key data include:~~

~~Dose dependent reductions~~Efficacy and Safety of ARO-APOC3 in ~~serum APOC3 (mean maximum reduction ranging from 72% in the 10 mg cohort~~Adults With Familial Chylomicronemia Syndrome
ClinicalTrials.gov Identifier: NCT05089084

ARO-C3 is designed to ~~94% in the 100 mg cohort), which were maintained through the end~~reduce production of ~~the study.~~

~~Dose dependent reduction in triglycerides andVLDL-C~~ ~~(mean maximum triglyceride reduction ranging from 53% in the 10 mg cohort and 64% in the 100 mg cohort and mean maximumVLDL-C~~ ~~ranging from 53% in the 10 mg cohort to 68% in the 50 mg cohort). These reductions were maintained through the end of study.~~

~~ARO-HIF2~~ ~~is being developed~~complement component 3 (C3) as a ~~treatment~~potential therapy for patients with ~~clear cell~~various complement mediated or complement associated renal ~~cell carcinoma (ccRCC). ccRCC~~and hematological diseases. Arrowhead is ~~one~~currently investigating ARO-C3 in a Phase 1/2 clinical trial.

•Paroxysmal Nocturnal-Hemoglobinuria: Paroxysmal nocturnal hemoglobinuria (PNH) is a rare, acquired, clonal disorder involving hematopoietic stem cells and is characterized by destruction of ~~the most common forms of kidney cancer. Most patients with ccRCC have a mutation in the Von Hippel-Lindau gene, rendering them unable to degrade~~red blood cells,

~~HIF-2a,~~
~~which leads to accumulation during tumor hypoxia and promotes tumor growth.~~

~~2019: Investigational New Drug application (IND) filed.~~


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~~ARO-HSD~~ ~~is being developed as~~

blood clots, and impaired bone marrow function. Silencing hepatic C3 expression may be a viable therapeutic approach for systemic C3 inhibition in PNH.

•Complement-Mediated Renal Disease: A number of rare renal diseases result from uncontrolled activation of the alternative pathway of complement, leading to progressive glomerular damage, proteinuria, hematuria, and impaired kidney function, and often resulting in end-stage renal disease (ESRD). In addition, dysregulation of the alternative complement pathway has been shown to play a role in the pathogenesis and progression of disease in some of the more common glomerulopathies. Silencing C3 may be a therapeutic approach for treatment ~~for patients with alcohol related~~of these conditions.

•Study Name: Study of ARO-C3 in Adult Healthy Volunteers and ~~nonalcohol related liver diseases such as nonalcoholic steatohepatitis (NASH).~~Patients With Paroxysmal Nocturnal Hemoglobinuria and Complement-Mediated Renal Disease~~ARO-HSD~~
A Phase 1/2a Dose-Escalating Study to Evaluate the Safety, Tolerability, Pharmacokinetics, and/or Pharmacodynamics of ARO-C3 in Adult Healthy Volunteers and in Adult Patients With Paroxysmal Nocturnal Hemoglobinuria and Adult Patients With Complement-Mediated Renal Disease
ClinicalTrials.gov Identifier: NCT05083364

ARO-RAGE is designed to reduce ~~the~~ production of ~~HSD17B13,~~the Receptor for Advanced Glycation End products (RAGE) as a ~~member~~potential treatment for various inflammatory pulmonary diseases. Arrowhead is currently investigating ARO-RAGE in a Phase 1/2 clinical trial.

•Study Name: Study of ARO-RAGE in Healthy Subjects and Patients With Asthma
A Phase 1/2a Study Evaluating the ~~hydroxysteroid dehydrogenase family involved~~Effects of ARO-RAGE in Healthy Subjects and Patients With Asthma ClinicalTrials.gov Identifier: NCT05276570

ARO-MUC5AC is designed to reduce production of mucin 5AC (MUC5AC) as a potential treatment for various muco-obstructive pulmonary diseases. Arrowhead is currently investigating ARO-MUC5AC in a phase 1/2 clinical trial.

•Study Name: Study of ARO-MUC5AC in Healthy Subjects and Patients With Asthma
A Phase 1/2a Study to Evaluate the ~~metabolism~~Effects of ~~hormones, fatty acids,~~ARO-MUC5AC in Healthy Subjects and bile acids. Published genetic data indicate a loss of function mutation in HSD17B13 provides strong protection against alcoholic hepatitis, cirrhosis, and NASH. This genetic validation gives us confidence about the target gene.

Patients with Asthma ClinicalTrials.gov Identifier: NCT05292950

~~2019: Clinical trial application filed.~~

Partnered Programs

The Takeda Pharmaceutical Company Limited

~~JNJ-3989~~Fazirsiran (formerly~~ARO-HBV)~~ ARO-AAT) is ana clinical-stage RNAi therapeutic candidate for the treatment of ~~chronic~~liver disease associated with alpha-1 antitrypsin deficiency. ARO-AAT is designed to knock down the Alpha-1 antitrypsin (“AAT”) gene transcript and reduce the hepatic production of the mutant AAT protein.

•Study Name: Study to Check the Safety of Fazirsiran and Learn if Fazirsiran Can Help People With Liver Disease and Scarring (Fibrosis) Due to an Abnormal Version of Alpha-1 Antitrypsin Protein
A Randomized, Double-blind, Placebo-Controlled, Phase 3 Study to Evaluate the Efficacy and Safety of Fazirsiran in the Treatment of Alpha-1 Antitrypsin Deficiency-Associated Liver Disease With METAVIR Stage F2 to F4 Fibrosis
ClinicalTrials.gov Identifier: NCT05677971

Janssen Pharmaceuticals

JNJ-3989 (also referred to as JNJ-73763989 and formerly referred to as ARO-HBV) is a subcutaneous RNAi therapy candidate which is designed to silence all HBV gene products and intervenes upstream of the reverse transcription process where current standard-of-care nucleotide and nucleoside analogues act. Arrowhead believes this, especially the elimination of hepatitis B ~~infection with~~surface antigen (HBsAg), may allow the ~~goal of achieving~~body’s natural immune defenses to clear the virus and potentially lead to a functional cure.~~JNJ-3989(ARO-HBV)~~ JNJ-3989 is ~~a next-generation subcutaneously administered compound that follows previous generation HBV compounds~~currently being investigated in multiple Phase 2 clinical trials being conducted by Janssen. The Phase 1/2a study and its preceding studies were conducted by Arrowhead.

~~ARC-520~~•Study Name: A Study of Different Combination Regimens Including JNJ-73763989 and/or JNJ-56136379 for the Treatment of Chronic Hepatitis B Virus Infection (REEF-1)
A Phase 2b, Multicenter, Double-blind, Active-controlled, Randomized Study to Investigate the Efficacy and Safety of Different Combination Regimens Including JNJ-73763989 and/or JNJ-56136379 for the Treatment

~~ARC-521.~~

~~2017:JNJ-3989(ARO-HBV)~~ ~~nominated; CTA filed.~~

	•		~~2018: Clinical trial commenced. Clinical data presented at the World Gastroenterologists Summit and at the AASLD Liver Meeting~~^® ~~2018 demonstrating:~~
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~~Mean HBsAg reduction~~

Table of Contents

~~-1.9~~2023 PROXY STATEMENT ~~Log10(-98.7%)~~Executive Compensation ~~with a range~~

of Chronic Hepatitis B Virus Infection
ClinicalTrials.gov Identifier: NCT03982186

~~-1.3~~• ~~Log10(-95.0%)~~ to~~-3.8~~ ~~Log10(-99.98%).~~

~~JNJ-3989(ARO-HBV)~~ ~~appeared~~Study Name: A Study of JNJ 73763989+JNJ 56136379+Nucleos(t)Ide Analog (NA) Regimen Compared to ~~be well-tolerated at monthly doses up~~NA Alone in e Antigen Negative Virologically Suppressed Participants With Chronic Hepatitis B Virus Infection
A Randomized, Double Blind, Placebo-controlled Phase 2b Study to ~~400 mg.~~

Evaluate Efficacy, Pharmacokinetics, and Safety of 48-week Study Intervention With JNJ 73763989+JNJ 56136379+Nucleos(t)Ide Analog (NA) Regimen Compared to NA Alone in e Antigen Negative Virologically Suppressed Participants With Chronic Hepatitis B Virus Infection
ClinicalTrials.gov Identifier: NCT04129554

•Study Name: A Study of JNJ-73763989 in Healthy Chinese Adult Participants
A Randomized, Open-Label, Parallel, Single Dose Study to Investigate Pharmacokinetics, Safety, and Tolerability of JNJ-73763989 in Healthy Chinese Adult Participants
ClinicalTrials.gov Identifier: NCT04586439

•Study Name: A Study to Evaluate the Effect of Hepatic Impairment on JNJ-73763989
A Phase 1, Single-Dose, Open-Label, Parallel-Group Study to Evaluate the Effect of Hepatic Impairment on the Pharmacokinetics of JNJ-73763989
ClinicalTrials.gov Identifier: NCT04208386

•Study Name: A Study of JNJ-73763989 + Nucleos(t)Ide Analog in Participants Co-Infected With Hepatitis B and Hepatitis D Virus (REEF-D)
A Phase 2, Multicenter, Randomized, Double-blind, Placebo-Controlled Study With Deferred Active Treatment to Investigate the Efficacy, Safety, and Pharmacokinetics of JNJ-73763989 + Nucleos(t)Ide Analog in Participants Co-Infected With Hepatitis B and Hepatitis D Virus
ClinicalTrials.gov Identifier: NCT04535544

•Study Name: A Study of JNJ-73763989 + JNJ-56136379 + Nucleos(t)Ide Analog (NA) Regimen With or Without Pegylated Interferon Alpha-2a (PegIFN-α2a) in Treatment-Naive Participants With Hepatitis B e Antigen (HBeAg) Positive Chronic Hepatitis B Virus (HBV) Infection and Normal Alanine Aminotransferase (ALT)
A Phase 2, Randomized, Open-label, Multicenter Study to Evaluate Efficacy, Pharmacokinetics, Safety, and Tolerability of Response-guided Treatment With JNJ-73763989 + JNJ-56136379 + Nucleos(t)Ide Analog Regimen With or Without Pegylated Interferon Alpha-2a in Treatment-naive Patients With HBeAg Positive Chronic Hepatitis B Virus Infection and Normal ALT
ClinicalTrials.gov Identifier: NCT04439539

•Study Name: A Study to Assess Intrahepatic and Peripheral Changes of Immunologic and Virologic Markers in Chronic Hepatitis B Virus Infection (INSIGHT)
A Phase 2 Randomized, Open-label, Parallel-group, Multicenter Study to Assess Intrahepatic and Peripheral Changes of Immunologic and Virologic Markers in Response to Combination Regimens Containing JNJ-73763989 and Nucleos(t)Ide Analog With or Without JNJ-56136379 in Patients With Chronic Hepatitis B Virus Infection
ClinicalTrials.gov Identifier: NCT04585789

•Study Name: A Study of JNJ-73763989 in Adult Participants With Renal Impairment
An Open-label, Single-dose, Parallel-group Study to Evaluate the Effect of Renal Impairment on the Pharmacokinetics of JNJ-73763989 in Adult Participants
ClinicalTrials.gov Identifier: NCT04963738

•Study Name: A Study of JNJ-73763989, Pegylated Interferon Alpha-2a and Nucleos(t)Ide Analogs in Participants With Chronic Hepatitis B Virus Infection (PENGUIN-2)
A Phase 2, Open-label, Multicenter Study to Assess Efficacy, Safety, Tolerability, and Pharmacokinetics of Treatment With JNJ-73763989, Nucleos(t)Ide Analogs, and Pegylated Interferon Alpha-2a in Patients With Chronic Hepatitis B Virus Infection
ClinicalTrials.gov Identifier: NCT05005507

	•		~~2018: Signed a license agreement with Janssen Pharmaceuticals, Inc., part of the Janssen Pharmaceuticals Companies of Johnson & Johnson, forJNJ-3989(ARO-HBV)~~ ~~and a collaboration agreement for up to three RNAi therapeutic candidates that use our proprietary TRiM~~^™ ~~platform against new targets to be selected by Janssen.~~
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~~The total potential deal value~~

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2023 PROXY STATEMENT Executive Compensation

•Study Name: A Study of JNJ-73763989, JNJ-56136379, Nucleos(t)Ide Analogs, and Pegylated Interferon Alpha-2a in Virologically Suppressed Participants With Chronic Hepatitis B Virus Infection (PENGUIN)
A Phase 2, Open-label, Single-arm, Multicenter Study to Assess Efficacy, Safety, Tolerability, and Pharmacokinetics of Treatment With JNJ-73763989, JNJ-56136379, Nucleos(t)Ide Analogs, and Pegylated Interferon Alpha-2a in Virologically Suppressed Patients With Chronic Hepatitis B Virus Infection
ClinicalTrials.gov Identifier: NCT04667104

JNJ-75220795 (formerly referred to as ARO-JNJ1) is ~~approximately $3.7 billion plus royalties on commercial sales.~~

~~Received $175 million as~~ an ~~upfront payment~~investigational therapeutic being developed by Janssen. It utilizes Arrowhead’s proprietary TRIMTM platform and ~~received $75 million~~is designed to reduce expression in the ~~form~~liver of ~~an equity investment by Johnson & Johnson Innovation — JJDC,~~patatin like phospholipase domain containing 3 (PNPLA3) as a potential treatment for patients with non-alcoholic steatohepatitis (NASH).

•Study Name: A Single and Multiple Ascending Dose Study of Subcutaneously Administered JNJ-75220795
A Double-Blind, Placebo-Controlled, Randomized, Multipart, Single and Multiple Ascending Dose Study to Investigate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Subcutaneously Administered JNJ-75220795
ClinicalTrials.gov Identifier: NCT04844450

•Study Name: A Study of JNJ-75220795 in Japanese Participants
A Double-Blind, Placebo-Controlled, Randomized, Single Ascending Dose Study to Investigate the Safety, Tolerability, Pharmacokinetics, and Pharmacodynamics of Subcutaneously Administered JNJ-75220795 in Japanese Participants
ClinicalTrials.gov Identifier: NCT05039710

Amgen Inc.~~, at a premium price of $23.00 per share of Arrowhead common stock.~~

~~2019: Arrowhead initiated dosing in the triple combination cohort (cohort 12) in the Company’s ongoing Phase 1 / 2 study ofJNJ-3989(ARO-HBV)~~
~~earning a $25 million milestone payment. The Company earned an additional $25 million milestone payment following the initiation of dosing in its phase 2b study of~~

~~JNJ-3989(ARO-HBV).~~

~~2019: Janssen selected one of its three potential targets under the 2018 collaboration agreement and the Company is developing a drug,ARO-JNJ1,~~ ~~under the collaboration.~~

Olpasiran (formerly AMG 890 ~~(formerly~~and ARO-LPA) is designed to reduce production of apolipoprotein A, a key component of lipoprotein(a), which has been genetically linked with increased risk of cardiovascular diseases, independent of cholesterol and LDL levels.

~~2016:~~ Amgen ~~Inc. acquired~~completed a ~~worldwide, exclusive license to develop~~Phase 2 clinical study evaluating the efficacy, safety, and ~~commercialize AMG 890(ARO-LPA)~~tolerability of Olpasiran in subjects with elevated levels of lipoprotein(a).

~~2018:~~ Amgen ~~administers~~reported Phase 2 clinical results at the ~~first dose~~American Heart Association (AHA) Scientific Sessions in November 2022 and simultaneously published in the New England Journal of ~~AMG 890(ARO-LPA)~~Medicine. Olpasiran is currently being evaluated in a Phase ~~1 clinical~~3 study ~~which earned Arrowhead~~to assess its impact on major cardiovascular events in participants with atherosclerotic cardiovascular disease and elevated lipoprotein(a), in a ~~$10~~double-blind, randomized, placebo-controlled, multicenter study. In December 2022, Amgen enrolled the first subject to its Phase 3 trial of Olpasiran, triggering a $25 million milestone ~~payment.~~

payment to Arrowhead.

~~ARO-AMG1~~• ~~was being developed against an undisclosed genetically-validated cardiovascular target under a license~~Study Name: A Study Olpasiran Trials of Cardiovascular Events and ~~collaboration agreement with Amgen. We completed~~Lipoprotein(a) Reduction (OCEAN(a)) - Outcomes Trial
A Double-blind, Randomized, Placebo-controlled, Multicenter Study Assessing the ~~Arrowhead Deliverable, as defined~~Impact of Olpasiran on Major Cardiovascular Events in ~~our collaboration agreement with Amgen, during 2018. The option period expired on August 7, 2019,~~Participants With Atherosclerotic Cardiovascular Disease and ~~Amgen advised the Company it did not intend to exercise its option.~~

~~Candidates in Development~~

Elevated Lipoprotein(a)
ClinicalTrials.gov Identifier: NCT05581303

GlaxoSmithKline Intellectual Property (No. 3) Limited (“GSK”)

~~ARO-ENaC~~ARO-HSD is designed to reduce production of ~~the epithelial sodium channel alpha subunit (~~HSD17B13, a~~ENaC)~~ hydroxysteroid dehydrogenase involved in the ~~airways~~metabolism of hormones, fatty acids and bile acids. Published human genetic data indicate that a loss of function mutation in HSD17B13 provides strong protection against nonalcoholic steatohepatitis (NASH) cirrhosis and alcoholic hepatitis and cirrhosis. Arrowhead completed a Phase 1/2 clinical trial and GSK is preparing to begin a Phase 2b clinical trial.

Nonalcoholic Steatohepatitis: NASH is liver inflammation and damage caused by a buildup of fat in the liver. This can cause scarring of the ~~lung. In cystic fibrosis patients, increased ENaC activity contributes~~liver and in advanced cases can lead to ~~airway dehydration~~cirrhosis.

•Study Name: Study of ARO-HSD in Healthy Volunteers and ~~reduced mucociliary transport.~~ Patients With Non-Alcoholic Steatohepatitis (NASH) or Suspected NASH
A ~~CTA is planned for~~Phase 1/2a Single and Multiple Dose-Escalating Study to Evaluate the ~~first half~~Safety, Tolerability, Pharmacokinetics and Pharmacodynamic Effects of ~~2020.~~

~~Financial Results~~

ARO-HSD in Normal Healthy Volunteers as Well as in Patients With NASH or Suspected NASH
ClinicalTrials.gov Identifier: NCT04202354

•

~~Revenue~~ ~~— Generated revenue of $168.8 million in fiscal 2019, compared to revenues of $16.1 million in fiscal 2018 and $31.4 million in fiscal 2017;~~

•

~~Net Income~~ ~~— Recorded net income of $68.0 million in fiscal 2019, compared to net losses of $54.5 million in fiscal 2018 and $34.4 million in fiscal 2017;~~

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Horizon Therapeutics plc

HZN-457 (formerly ARO-XDH) is designed to reduce production of xanthine dehydrogenase (XDH) as a potential treatment for people with uncontrolled gout. In December 2022, Horizon enrolled its first subject in a Phase 1 randomized, placebo-controlled trial to assess the safety, tolerability, pharmacokinetics and pharmacodynamics of its development-stage medicine HZN-457. The enrollment of its first subject triggered a $15 million milestone payment to Arrowhead.

Financial Results

•Revenue — Generated revenue of $243.2 million, compared to revenues of $138.3 million in fiscal 2021 and $88.0 million in fiscal 2020;

•Net Loss — Recorded net loss of $176.1 million, compared to net losses of $140.8 million in fiscal 2021 and $84.6 million in fiscal 2020;

•Net Loss Per Share — Recorded net loss per share (diluted) of $1.67, compared to net loss per share (diluted) of $1.36 in fiscal 2021 and $0.84 in fiscal 2020;

•Cash at end of fiscal 2022 — Cash and investments of cash totaled $482 million at September 30, 2022; and

•Total Stockholder Return — Achieved a three-year total stockholder return (“TSR”) at the 50th percentile of our peer group as measured in September 2022. Since 2017, our stockholder return has compared exceptionally well against relevant indices.

The comparisons in the above graph are based on historical data and are not intended to forecast the possible future performance of our common stock.

	•		*~~Net Income Per Share~~* ~~— Recorded net income per share (diluted) of $0.69 in fiscal 2019, compared to net losses per share (diluted) of $0.65 in fiscal 2018 and $0.47 in fiscal 2017.~~
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~~Cash at end of fiscal 2019~~ ~~— Cash and investments of cash totaled $302.9 million at September 30, 2019, and $528 million as of December 31, 2019.~~

•

~~Total Stockholder Return~~ ~~— 47% in fiscal 2019.~~

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Executive Compensation Highlights

Say-on-Pay Vote and Response to Stockholder Feedback

At our 2022 Annual Meeting of Stockholders, 20.4% of the stockholder votes cast on our non-binding, advisory proposal (the “Say-on-Pay” vote) on the executive compensation program were in favor of the program. Our Board of Directors was disappointed with this result as well as the failure of Dr. Perry, Dr. Ferrari, and Mr. Waddill, members of the Compensation Committee, to receive a majority of the votes cast on their respective re-election to our Board, which we believe was largely due to concerns about our executive compensation program. Based onfeedback from our stockholders as well as proxy advisory firms, we understand that concerns with our executive compensation program relate primarily to the quantum of equity in our long-term incentive compensation arrangements for our CEO, Dr. Anzalone.

In response to the results of the 2021 and 2022 Say-on-Pay and to address the stockholder concerns that were voiced, the Compensation Committee determined it would revise the equity award that was granted to our CEO on January 2, 2022 (as described below).

Our CEO’s Fiscal 2022 Equity Award

In revising the January 2, 2022 equity award, the Compensation Committee relied on a competitive market analysis prepared by its compensation consultant. The Compensation Committee determined it would seek to revise the equity award to achieve a total direct compensation program meeting that of the median total direct compensation of CEOs among the peer group. The Compensation Committee, after noting the median compensation level of the chief executive officers of the companies in our compensation peer group, opted to limit the size of our CEO’s fiscal 2022 equity award to an amount equal to the difference between this median compensation level and our CEO’s target total cash compensation opportunity for fiscal 2022. After dividing this dollar amount by the market value of our common stock on the proposed date of the grant revision (July 8, 2022), the Compensation Committee revised our CEO’sequity award from its original 800,000 shares to an award covering a total of 248,083shares of our common stock, comprising two separate awards.

•The first award representing 40% of the total value of our CEO’s fiscal 2022 equity compensation was granted in the form of a time-based restricted stock unit (“RSU”) award covering 99,521 shares, subject to annual service-based vesting over a four-year period beginning on January 1, 2023. Each unit granted pursuant to the RSU award represents a contingent right to receive one share of our common stock for each unit that vests over the four-year vesting period.

•The second award for the remaining 60% of the total value of our CEO’s fiscal 2022 equity incentive was granted in the form of a performance-based RSU (“PRSU”) award covering 149,282 shares eligible to vest upon the achievement of each of three performance goals as follows, but only if each performance goal is achieved on or before July 8, 2026:


Performance Goal	Number of Shares That Will Vest Upon Achievement of Performance Goal (#)	Vesting Deadline
Initiation by the Company of a Phase 3 clinical study of an investigation drug for a non-orphan indication	49,761	July 8, 2026

Initiation of a Phase 2 Study by the Company or one of its licensees for one of the Company’s non-hepatocyte targeted investigational drugs	49,761	July 8, 2026

Achievement of 15 Arrowhead-discovered drugs in clinical study or clinical use (inclusive of wholly-owned and outlicensed drugs).	49,760	July 8, 2026


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The Compensation Committee believes achievement of these goals represent potential value milestones for the company.

Each unit granted pursuant to the PRSU award represents a contingent right to receive one share of our common stock for each unit that is earned and vests. In the event that our CEO’s employment with us is terminated for cause before the vesting of all or any portion of his RSU award and/or PRSU award, the then-unvested portion of such awards will immediately terminate and be forfeited.

Stockholder Engagement

As an additional response to the results of the Say-On-Pay vote at our 2022 Annual Meeting of Stockholders, our Board directed our Corporate Secretary and the Compensation Committee Chair to reach out to our principal stockholders to discuss and better understand the reasons for their votes, including the concerns about our executive compensation program and the director retention votes for Dr. Perry, Dr. Ferrari, and Mr. Waddill, and to ensure the changes we made to our CEO’s 2022 compensation adequately addressed the concerns leading to the prior voting results. During the summer and fall of 2022, our Corporate Secretary and Mr. Waddill, the Compensation Committee Chair, requested meetings with 25 stockholders (beneficially owning in the aggregate 52% of the outstanding shares of our common stock (or approximately 79% of votes cast at the 2022 Annual Meeting)) to discuss our executive compensation program and their views on other matters related to the Company. Six of those stockholders, which collectively beneficially owned 22%of the outstanding shares of our common stock (or approximately 34% of votes cast at the 2022 Annual Meeting) and were all among our top 20 largest stockholders, spoke to our Corporate Secretary and Mr. Waddill. Of the six stockholders engaging in these discussions, five voted against our 2022 Say-on-Pay proposal and one voted in favor of it. Of those stockholders who voted against our 2022 Say-on-Pay proposal, each stated that their primary concern about the proposal was the quantum of stock awarded to our CEO in fiscal 2021. All six of the stockholders who engaged with us stated that the revisions made mid-2022 to our CEO's equity award in 2022, as well as the Compensation Committee’s commitment that it intended to make a similarly structured award to the CEO in January 2023, and a representation that the Compensation Committee had no present intention to make any future awards inconsistent with that methodology, fully resolved the material concerns of these stockholders that had led to their respective votes in 2022 on named executive officer compensation and director retention.

Below is a summary of our outreach process:


Say on Pay Vote:			March 17, 2022
Say on Pay Support:			20.4% of votes cast (% of votes For / For + Against)
Engagement Period:			Between November 2022 and January 2023
Breadth of Outreach:			Top 25 institutional stockholders representing 52% of outstanding common stock (or approximately 79% of votes cast at the 2022 Annual Meeting)
Breadth of Engagement:			Six stockholders representing 22% of outstanding common stock (or approximately 34% of our votes cast at the 2022 Annual Meeting)
Participants:			Mr. Waddill, the Compensation Committee Chair, and our Corporate Secretary

Below is a summary of our stockholder feedback:


What We Heard			How We Responded


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Of those stockholders who voted against our 2022 Say-on-Pay proposal, each stated that their primary concern was the quantum of stock awarded to the CEO in 2021.			As noted above, in July 2022, the Compensation Committee revised our CEO’s compensation to the median compensation of his peers by revising his equity award from its original 800,000 shares to an award covering a total of 248,083 shares of our common stock, comprising two separate awards. All six of the stockholders who engaged with the Company stated that the revisions made mid-2022 to the CEO stock award in 2022, as well as the Compensation Committee’s commitment that would not make a similar award to the CEO in January 2023, and a representation that the Compensation Committee had no present intention to deviate from a median total compensation strategy, fully resolved any material concerns they had leading to their respective votes in 2022 on executive compensation and director retention.
Stockholders requested that we provide additional disclosure around our annual incentive goals.			As described further below under Annual Incentive Compensation, the Compensation Committee provided enhanced disclosure of the qualitative objectives, including specific targets and achievements, taking into account and being respectful of the competitive harm that could occur by disclosing sensitive R&D achievements.
One Stockholder expressed concern that our Board lacked a sufficient number of women.			In May 2022 the Board added another woman. The Stockholder expressed satisfaction with the Board’s efforts toward diversification.

Aggressive Performance Fueled by Incentives

The Compensation Committee expects and has observed aggressive performance from the entire executive management team as evidenced by stockholder return as compared against major indices and our compensation peer group. Our philosophy has been to foster this expectation with reasonably aggressive incentive compensation. Based on our overall operating environment, feedback from our stockholders, and ~~these~~stockholder return results, in addition to the modifications to our CEO's compensation described above, the Compensation Committee took the following key actions and maintained key policies with respect to the compensation of all of our ~~Named Executive Officers~~NEOs for ~~2019:~~

fiscal 2022:

•Base Salary — Approved base salary increases for our current NEOs based on performance and market adjustments.

•Annual Incentive Compensation — Certified performance and approved annual cash bonuses for our NEOs for fiscal 2022 in amounts of up to 100% of their target annual cash incentive compensation opportunities, including an annual cash bonus for our CEO in the amount of $783,315, equal to 90% of his target annual cash incentive compensation opportunity.

•Equity Compensation — In addition to the modified equity award for our CEO described above, the Compensation Committee granted our other NEOs long-term incentive compensation opportunities in the form of time-based RSU awards that may be settled for shares of our common stock with grant date values ranging from $2.0 million to $2.3 million. The awards vest in four equal annual installments beginning in 2023.

•Clawback Policy — Maintained a clawback policy allowing Arrowhead to recover incentive compensation from our executive officers should our Board determine that a material misstatement of our financial statements was due to fraud, negligence or intentional misconduct by any such executive officer.

•Stock Ownership Guidelines — Maintained guidelines mandating ownership of Arrowhead stock in amounts equal to, for our CEO, six times annual base salary and, for our CFO, two times annual base salary.

•“Double Trigger” Feature for Acceleration of Equity Awards — Maintained the agreements for outstanding equity awards granted to our CEO pursuant to our 2013 and 2021 Incentive Plans to provide that, upon a change in control of Arrowhead, the vesting of such awards will accelerate only in the event of a subsequent involuntary termination of employment (i.e., on a “double-trigger” basis).

	•		*~~Base Salary~~* ~~— Approved base salary increases of4-10%~~ ~~for our current Named Executive Officers, including a 5% increase for our CEO.~~
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~~Annual Incentive Compensation~~ — Approved annual cash bonuses for 2019 ranging from 130% to 243% of target annual incentive compensation opportunities, including an annual cash bonus for our CEO in the amount of $1,540,000, equal to 226% of his target annual incentive compensation opportunity.

•

~~Equity Compensation~~ ~~— Granted our CEO a long-term incentive compensation opportunity in the form of a performance-based restricted stock unit (“~~~~PRSU~~~~”) award with a grant date value of $7,452,000. This CEO PRSU award will vest upon the achievement of three equally weighted,~~

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2023 PROXY STATEMENT ~~pre-established~~ and rigorous performance milestones. The Compensation Committee also granted our other Named Executive Officers long-term incentive compensation opportunities in the form of time-based restricted stock unit (“~~RSU~~”) awards that may be settled for shares of our common stock with grant date values ranging from $869,400 to $2,608,200. A minimum three-year vesting is required for time-based equity awards granted to our other executive officers.

•

~~Clawback Policy~~ — Maintained a clawback policy allowing the Company to recover compensation from any executive officer should the Board determine that a material misstatement of the Company’s financial statements was due to fraud, negligence, or intentional misconduct by any executive officer of the Company.

•

~~Ownership Guidelines~~ ~~— Maintained the achievement of stock ownership guidelines of six times his annual base salary for our CEO and twice their annual base salary for our COO and CFO.~~

•

~~“Double Trigger” Feature for Acceleration of Equity Awards~~ — Maintained the agreements for outstanding equity awards granted to our CEO pursuant to our 2004 Equity Incentive Plan and 2013 Incentive Plan to provide that, upon a change in control of the Company, the vesting of such awards will accelerate only in the event of a subsequent involuntary termination of employment (a “double-trigger” arrangement).

~~Advisory Vote to Approve Named~~ Executive ~~Officer~~ Compensation

At our 2019 Annual Meeting of Stockholders, ~~in March 2019, we conducted anon-binding~~ ~~stockholder advisory vote to approve the compensation of our Named Executive Officers (commonly known as a“Say-on-Pay”~~ ~~vote). Our stockholders approved theSay-on-Pay~~ proposal with approximately 97% of the votes cast in favor of the proposal. Based on the vote and feedback from our stockholders, we attribute the high approval percentage primarily to the following factors:

~~Continued our practice of granting 100% performance-based equity awards for our CEO which is preferred by stockholders and unusual in our peer group;~~

Maintained our commitment to good corporate governance by continuing the following compensation practices: minimum vesting requirements; compensation recovery (“clawback”) policy, double-trigger acceleration of equity awards for our CEO; and stock ownership guidelines for our CEO, CFO and COO;

~~Achievement of aggressive corporate goals in 2018 and 2019; and~~

~~Substantial increases in market capitalization and TSR in 2018 and 2019.~~

In 2019, we continued our stockholder engagement program, reaching out to our top 20 institutional stockholders beneficially owning over 50% of our outstanding common stock to solicit their views and concerns and reviewed the feedback and policies of ISS. Based on this review, as well as our commitment to good corporate governance, as noted above, the Compensation Committee continued the above mentioned practices for the executive compensation review in 2019.

~~During our 2019 annual meeting in March 2019,~~ we asked our stockholders to recommend the frequency of future Say-on-Pay stockholder advisory votes on the compensation of ~~the Company’s named executive officers. Stockholders~~our NEOs. Our stockholders recommended an annual Say-on-Pay non-binding vote, and ~~we are following~~our Board of Directors has decided continue to follow that recommendation.


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~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

We value the opinions of our stockholders and will continue to consider the outcome of futureSay-on-Pay votes, as well as feedback received throughout the year, when making compensation decisions for our executive officers. The Compensation Committee is committed to being responsive to stockholder feedback regarding our executive compensation program, policies, and practices, including concerns expressed through theSay-on-Pay vote.

Pay-for-Performance Analysis

We believe our executive compensation program is reasonable, competitive, and appropriately balances the goals of attracting, motivating, rewarding, and retaining our executive officers with the ~~goal~~objective of aligning their interests with those of our stockholders. To ensure this alignment and to motivate and reward individual initiative and effort, a significant portion of our executive officers’ target ~~annual~~ total direct compensation opportunity is both performance-based and~~“at-risk.~~ “at-risk.”

We emphasize performance-based compensation that appropriately rewards our executive officers, including our ~~Named Executive Officers,~~NEOs, through two separate compensation elements:

•First, we provide the opportunity to participate in our annual incentive compensation plan which provides cash payments if ~~they~~executive officers produce short-term financial, operational, and strategic results that meet or exceed the objectives set forth each year in our annual operating plan.

•In addition, we grant equity awards as long-term incentive compensation. For our CEO in fiscal ~~2019, this~~2022, as described above, 60% of his equity award is to be earned based ~~entirely~~ on the achievement ofpre-established corporate ~~performance~~ objectives ~~which~~that are ~~both challenging~~substantial and designed to drive our financial and operational performance and long-term growth, and, in the case of our other executive officers, are either dependent on the future appreciation in value of our common stock or are subject to the risk of fluctuations in the value of our common stock and, therefore, are “at risk.”

~~The pay mix for our CEO for each of the last three fiscal years illustrates the ongoing emphasis on our performance-based compensation philosophy~~:

We believe that, ultimately, the creation of sustainable long-term stockholder value will depend on our ability to successfully bring to market the products we develop or ~~partner~~our success in partnering with strategic collaborators to bring them to market. Consequently, the Compensation Committee strives to incent our executive officers to create that value through the discovery and development of a robust and attractive pipeline of drug candidates. ~~As a result,~~To achieve that end, our executive compensation program is designed to provide incentives that facilitate these efforts. Particularly for our CEO, the Compensation Committee has awarded ~~performance milestone-based~~60% of his long term incentive compensation as performance-based equity awards ~~directly linked~~designed to ~~goals that promote the development of our pipeline and other related business and market-based objectives.~~produce stockholder value. The Compensation Committee closely tracks the progress against these objectives ~~to monitor~~and, in conjunction with the independent members of our ~~success over each product’s development period and evaluates our executive officers primarily on that progress.~~

Board, ensures the objectives are met using sound, ethical business practices before certifying performance achievement of the awards.

To ensure that we remain faithful to our compensation philosophy, the Compensation Committee regularly evaluates the relationship between the reported values of the equity awards granted to our executive officers, the amount of compensation realizable (and, ultimately, realized) from such awards in subsequent years, and our total stockholder return over this period.


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~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Executive Compensation Policies and Practices

We endeavor to maintain sound governance standards consistent with our executive compensation policies and practices. The Compensation Committee evaluates our executive compensation program on a regular basis to ensure that it is consistent with our short-term and long-term goals given the dynamic nature of our business and the market in which we compete for executive talent. The following summarizes our executive compensation and related policies and practices:


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WHAT WE DO

WHAT WE DON’T DO

✓ Maintain an Independent Compensation Committee. The Compensation Committee consists solely of independent directors.

✓ Retain an Independent Compensation Advisor. The Compensation Committee engaged its own compensation advisor to provide information and analysis with its ~~2019~~fiscal 2022 compensation review, and other advice on executive compensation independent of management. This consultant performed no consulting or other services for us in ~~2019.~~

fiscal 2022.

✓Annual Executive Compensation Review. ~~Executive~~ ~~Compensation~~ ~~Review~~. The Compensation Committee conducts an annual review and approval of our compensation strategy, including a review and determination of our compensation peer group ~~used for comparative purposes~~ and a review of our compensation-related risk profile to ensure that our compensation programs do not encourage excessive or inappropriate ~~risk-taking and that the level of risk that they do encourage is not reasonably likely to have a material adverse effect on us.~~

risk-taking.

✓Compensation At-Risk.~~At-Risk~~. Our executive compensation program is designed so that a significant portion of compensation is “at risk” based on our performance, as well as short-term cash and long-term equity incentives to align the interests of our executive officers and stockholders.

✓CEO Annual Incentive Compensation Cap. Our CEO’s annual cash incentive compensation opportunity is capped at 150% of his base salary.

✓Stock Ownership Policy. We maintain a stock ownership policy that requires our CEO ~~COO,~~ and CFO to maintain a minimum ownership level of our common stock.

✓Compensation Recovery (“Clawback”) Policy. We have established a clawback policy allowing ~~the Company~~us to recover compensation should ~~the~~our Board determine that a material misstatement of ~~the Company’s~~our financial statements was due to fraud, negligence or intentional misconduct by any executive officer of the Company.

✓Conduct an Annual Stockholder Advisory Vote on ~~Named Executive Officer~~NEO Compensation. We conduct an annual stockholder advisory vote on the compensation of our ~~Named Executive Officers.~~

NEOs.

✓Use a Pay-for-Performance Philosophy.~~Pay-for-Performance~~ ~~Philosophy.~~ The majority of our CEO’s compensation is directly linked to ~~corporate performance;~~achievement of milestones to the benefit of all stakeholders; we also structure target total direct compensation opportunities with a significant long-term equity component, thereby making a substantial portion of ~~the~~our CEO’s and each additional executive officer’s target total direct compensation dependent upon our stock price and/or total stockholder return.

✓“Double Trigger” Feature for Acceleration of CEO Equity Awards — The outstanding equity awards granted to our CEO pursuant to our ~~2004 Equity~~2013 Incentive Plan and ~~2013~~2021 Incentive Plan provide that, upon a change in control of the Company, the vesting of such awards will accelerate only in the event of a subsequent involuntary termination of employment ~~(a“double-trigger”~~(a “double-trigger” arrangement).

×✘ No Executive Retirement ~~Plans~~Plans.. We do not offer pension arrangements or retirement plans or arrangements to our executive officers that are different from or in addition to those offered to our other employees.

×✘ No Perquisites. ~~Currently, we~~ We do not provide perquisites or other personal benefits to our executive officers.

×✘No Special Welfare or Health Benefits. No ~~Special~~ ~~Welfare~~ or ~~Health~~ ~~Benefits.~~ Our executive officers participate in broad-based Company-sponsored health and welfare benefits programs generally on the same basis as our other full-time, salaried ~~employees, except for a premium for life insurance for our CEO.~~

employees.

×✘No Post-Employment Tax Payment Reimbursement. ~~Post-Employment~~ ~~Tax~~ ~~Payment~~ ~~Reimbursement.~~ We do not provide any tax reimbursement payments (including~~“gross-ups”~~ “gross-ups”) on any severance orchange-in-control payments or benefits.

×✘No Hedging and Limit on Pledging of Our Equity Securities. We prohibit our employees, executive officers and thenon-employee members of our Board from hedging our equity securities. ~~Executive~~Our board members and executive officers may pledge up to 50% of owned and vested shares with the approval of ~~the~~our Board.

×✘No Dividends or Dividend Equivalents Payable on Unvested Equity Awards. We do not pay dividends or dividend equivalents on unvested RSU awards or PRSU awards.

×✘No Stock OptionRe-pricing. Our employee stock plan does not permit options to purchase shares of our common stock to be repriced to a lower exercise or strike price without the approval of our stockholders.


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Executive Compensation Philosophy

Our executive compensation philosophy reflects our two fundamental objectives:

•to attract, motivate and retain a highly skilled team of executives; and

•to align our executive officers’ interests with those of our stockholders by rewarding short-term and long-term performance and aligning compensation to increases in stockholder value.

We believe that the compensation of our executive officers should be directly linked to the achievement of specific objectives that are expected to increase stockholder value. In furtherance of this goal, the Compensation Committee has established the following guidelines as a foundation for compensation decisions:

•provide a competitive total compensation package that enables us to attract, retain and motivate highly-qualified executives with the skills and experience required for the achievement of business goals;

•promote the achievement of key strategic and financial performance measures by linking short-term and long-term compensation to the achievement of measurable goals;

•reward significant achievements outside of pre-established goals;

~~pre-established~~• ~~goals;~~

recognize that pharmaceutical research, development and commercialization require sustained and focused effort over many years, and involve a high degree of risk and therefore balance incentives for short-term and long-term compensation;

•employ ~~outside~~external compensation expertise and market data from industry peers to help assure that our compensation policies and practices are consistent with industry practice and meet our goals for our compensation program;

•consider our cash resources and cost of capital to balance cash and equity compensation; and

•align our ~~executive officers’~~executives’ incentives with the creation of stockholder value.

Executive Compensation Program Design

Our practice is to combine a mixture of compensation elements that balance achievement of our short-term goals with our longer-term performance. Currently, our executive compensation program consists of three principal elements:

•base salary;

•an annual cash incentive compensation opportunity; and

•long-term incentive compensation in the form of equity awards.

We believe that cash compensation in the form of base salary and an annual incentive compensation opportunity provides our executive officers with short-term rewards for success in operations, and that long-term incentive compensation in the form of RSU and PRSU awards that may be settled for shares of our common stock, and options to purchase shares of our common stock, align the objectives of our executive officers with those of our stockholders with respect to long-term performance and success.

The Compensation Committee takes into consideration, among other things, our financial and working capital condition when approving performance objectives and making compensation decisions for our executive officers. Since we seek to ~~preserve~~invest our cash prudently and do not have marketed products, overall target total direct compensation opportunities are weighted more heavily toward long-term incentive compensation in the form of equity awards. Thus, a significant portion of each executive officer’s target total direct compensation opportunity is “at risk,” and dependent on the increase in the value of our common stock. The Compensation Committee periodically reassesses the appropriate weighting of cash and equity compensation.

In the case of long-term incentive compensation, typically the Compensation Committee designs these awards to vest, or be earned, over a multi-year period, meaning that long-term value creation, contrasted with short-term gain, presents the best opportunity for our executive officers to benefit from their awards.

We do not maintain a specific policy on the percentage allocation between short-term and long-term incentive compensation elements.

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Governance of Executive Compensation Program

Role of the Compensation Committee

The Compensation Committee discharges many of the responsibilities of our Board relating to the compensation of our executive officers, including our ~~Named Executive Officers,~~NEOs, and thenon-employee members of our Board. The Compensation Committee has overall responsibility for overseeing our compensation and benefits philosophy and policies generally, overseeing and evaluating the compensation plans, policies and practices applicable to our CEO and our other executive officers, and ensuring that the target total direct compensation opportunities of our executive officers, including our ~~Named Executive Officers,~~NEOs, are consistent with our compensation philosophy, policies and objectives.

The members of the Compensation Committee are appointed by our Board, and each member is an independent director (as “independence” is currently defined in Rule 5605(a)(2) of ~~the~~ Nasdaq listing standards). Currently, the members of the Compensation Committee are William Waddill (Committee Chair), Marianne De Backer, Adeoye Olukotun, and Michael ~~S. Perry (Chairman), Mauro Ferrari, and William Waddill.~~

Perry.

The Compensation Committee reviews our executive compensation program annually on a calendar year basis, generally in December. The Compensation Committee draws on a number of resources to assist in the evaluation of the various ~~components~~elements of our executive compensation program including, but not limited to, feedback from our stockholders, input from our CEO, the advice of an external compensation consultant (as identified below) retained by the Compensation Committee, information provided in the public filings of industry peers and industry data compiled yearly by Radford in its Global Life Sciences Survey, which represents a nationally-based assessment of executive compensation widely used within the pharmaceutical and biotechnology industry sectors.

The Compensation Committee relies upon the judgment of its members in making compensation decisions. In addition, the Compensation Committee incorporates its members' judgment in the assessment process to respond to and adjust for the evolving business environment. The members of the Compensation Committee have extensive experience in executive management, as well as compensation practices and policies.

Compensation-Setting Process

The Compensation Committee develops recommendations for the target total direct compensation opportunities for our executive officers, including our ~~Named Executive Officers.~~NEOs. The Compensation Committee does not use a single method or measure in making its compensation decisions, nor does it ordinarily position compensation levels based upon a specific or target level relative to a compensation peer group or other companies. Nonetheless, the pay practices at other companies are an important factor that the Compensation Committee considers in assessing the reasonableness of compensation and ensuring that our compensation practices are competitive in the marketplace.

Generally, the Compensation Committee evaluates the compensation of our executive officers relative to the median of the competitive market. However, as discussed hereafter, various other factors are taken into consideration in determining our executive officers’ compensation and the Compensation Committee does not target compensation at any specific level relative to the competitive market. When reviewing our current executive compensation arrangements and approving each compensation element and the target total direct compensation opportunity for our executive officers, the Compensation Committee considers the following factors:

•Our performance against the financial and operational objectives established by the Compensation Committee and our Board;

•Each individual executive officer’s skills, experience and qualifications relative to other similarly-situated executives at the companies in our compensation peer ~~group;~~

group and in selected broad-based compensation surveys;

•The scope of each executive officer’s role compared to other similarly-situated executives at the companies in our compensation peer ~~group;~~

group and in selected broad-based compensation surveys;

•The performance of each individual executive officer, based on a subjective assessment of his or her contributions to our overall performance, ability to lead his or her business unit or function and work as part of a team, all of which reflect our core values;

•The compensation practices of our compensation peer group and the companies in selected broad-based compensation surveys and the positioning of each executive officer’s compensation in a ranking of peer company compensation levels; and


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•The recommendations provided by our CEO with respect to the compensation of our other executive officers.


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~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

These factors provide the framework for compensation decision-making and final decisions regarding the compensation opportunity for each executive officer. No single factor is determinative in setting pay levels, nor was the impact of any factor on the determination of pay levels quantifiable.

Role of Chief Executive Officer

In discharging its responsibilities, the Compensation Committee works with members of our management, including our CEO. Our management assists the Compensation Committee by providing information on corporate and individual performance, market compensation data and management’s perspective on compensation matters. The Compensation Committee solicits and reviews our CEO’s recommendations with respect to the compensation levels for individual executive officers other than himself based on ~~the~~his performance evaluation of each executive ~~officer’s manager and his own evaluation of the executive officer’s performance.~~

officer.

The Compensation Committee reviews and discusses these recommendations and proposals with our CEO and considers them as one factor in ~~formulating the recommendations for~~determining the compensation for our executive officers, including our other ~~Named Executive Officers.~~NEOs. Our CEO recuses himself from all discussions and recommendations regarding his own compensation.

Role of Compensation Consultant

The Compensation Committee engages an external compensation consultant to assist it by providing information, analysis and other advice relating to our executive compensation program and the decisions resulting from its annual executive compensation review. The Compensation Committee has the final authority to engage and terminate the engagement of any compensation consultant that it retains.

~~For the period from~~

Since October 2018, ~~through present,~~ the Compensation Committee has engaged Compensia ~~Inc. (“~~~~Compensia~~~~”), a national compensation consulting firm,~~ as its external compensation consultant. Compensia assisted the Compensation Committee in its review of executive officer andnon-employee director compensation practices for ~~2019,~~fiscal 2022, including the competitiveness of compensation levels, executive compensation design, comparisons with our industry peers, and other technical ~~considerations, such as:~~

considerations. Such assistance included:

~~Review~~

•Reviewing and ~~update of~~updating our compensation peer group;

~~Review~~•Reviewing and ~~analysis of~~analyzing the compensation arrangements for our executive officers, including our ~~Named Executive Officers;~~

NEOs;

~~Review~~•Reviewing and ~~analysis of~~analyzing the compensation arrangements for thenon-employee members of our Board;

~~Review~~•Reviewing and ~~update~~updating of the Compensation Discussion and Analysis section of our proxy statement for our ~~2020~~2023 Annual Meeting of Stockholders; and

•

~~Support on other~~~~ad hoc~~ ~~matters.~~

•Supporting on other ad hoc matters.

The terms of Compensia’s engagement include reporting directly to the Compensation Committee and to the Compensation Committee ~~chair.~~

Chair.

In ~~2019,~~fiscal 2022, Compensia did not provide any ~~other~~ services to ~~us.~~us other than those described above. The Compensation Committee has evaluated Compensia’s independence pursuant to the listing standards of ~~the~~ Nasdaq and the relevant SEC rules and has determined that no conflict of interest has arisen as a result of the work performed by Compensia.

Competitive Positioning

For each of the past ~~six~~nine years, the Compensation Committee has directed its external compensation consultant to conduct a comparative study and report on compensation levels and practices relative to industry peers, including a competitive assessment of our executive compensation program as compared to the market data for base salaries, target total cash compensation, long-term incentive compensation and target total direct compensation. Typically, the findings of this study are presented to the Compensation Committee by the compensation consultant in conjunction with the Compensation Committee’s annual review of our executive compensation program.


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~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Because the biotechnology sector is dynamic, the comparator group used by the Compensation Committee to assess the competitive positioning of the compensation of our executive officers is updated annually to ensure that peer companies continue to meet the established criteria. For purposes of its review of our executive compensation


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program in fiscal ~~2019,~~2022, the Compensation Committee directed Compensia to update ~~its~~the compensation peer group reflecting the competitive market for executive talent based on the following criteria:

•Publicly-held,~~pre-commercial~~ U.S. biotechnology companies;

•Companies with lead assets that are in mid to late clinical stage or early commercialization stage;

•Companies with market capitalizations between ~~0.5x~~0.2x to ~~2.0x~~3.0x our market capitalization at the time of the peer selection; and

•Companies with between 50133 to ~~500~~1,453 employees.

The compensation peer group was selected in such a manner that our market capitalization was very near the median for all peer companies. Consideration was also given to the frequency or infrequency with which a company was identified as a peer with other peer companies. ~~The increase in the Company’s market capitalization indicated significant redesign of the peer group for 2019.~~

For ~~2019,~~fiscal 2022, the compensation peer group was generated in the first quarter of fiscal 2022 and consisted of the following companies:


ACADIA Pharmaceuticals, Inc.		FibroGen
Acceleron Pharma,		Inc.	Global Blood Therapeutics, Inc.
~~Assembly Biosciences~~Alnylam Pharmaceuticals, Inc.				~~Immunomedics~~Intellia Theraputics
~~Allogene Therapeutics~~		Biohaven Pharmaceutical Holding Company Ltd.	Mirati ~~Therapeutics~~Therapeutcis
~~Atara Biotherapeutics~~bluebird bio, Inc.,				~~MyoKardia~~
~~BioCryst Pharmaceuticals~~	~~Progenics Pharmaceutical~~Novavax
Blueprint Medicines		Reata Pharmaceuticals
BridgeBio Pharma		~~Rgel Pharmaceuticals~~Sarepta Therapeutics
ChemoCentryx				~~Sangamo Therapeutics~~Ultragenyx Pharmaceuticals
~~Dicerna Pharmaceuticals~~CRISPR Therapeutics AG				~~Xencor~~Vir Biotechnology
~~Geron~~Denali Therapeutics				~~Zogenix~~

Acceleron Pharma, Alnylam Pharmaceuticals, Biohaven Pharmaceutical, bluebird bio, and Global Blood Therapeutics were added to the compensation peer group due to changes in our business complexity, employee base and market capitalization, as well as mergers, changes to business complexity, employee base and market capitalization among our prior peer group.

The compensation study prepared by Compensia and presented in December ~~2019~~2021 provided an assessment of our compensation practices as compared to industry peers. Compensation levels for our executive officers, in the aggregate, were determined to be within the range of compensation provided to similarly placed executives and consistent with our compensation philosophy.

Individual Compensation Elements

In ~~2019,~~2022, the principal elements of our executive compensation program were as follows:

•base salary;

•an annual cash incentive compensation opportunity;

•long-term incentive compensation in the form of equity awards;

•welfare and health benefits; and

•post-employment compensation arrangements.

Base Salary

Base salary represents the fixed portion of the compensation of our executive officers, including our ~~Named Executive Officers,~~NEOs, and is an important element of compensation intended to attract and retain highly-talented individuals.


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The initial base salaries for our executive officers were negotiated on an individual basis at the time of hire. Thereafter, using the competitive market data provided by its external compensation consultant, the Compensation Committee reviews and determines adjustments to the base salaries for each of our executive officers, including our ~~Named Executive Officers,~~NEOs, as part of its annual executive compensation review. In addition, the base salaries of our executive officers may be adjusted by the Compensation Committee in the event of a promotion or significant change in responsibilities. Generally, the Compensation Committee sets base salaries with reference to the competitive range of the market median of our compensation peer group and applicable executive compensation survey data, as well as its assessment of the factors described in “Governance of Executive Compensation Program — Compensation-Setting Process” above.


24

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

The base salaries of our ~~Named Executive Officers~~NEOs for ~~2018~~fiscal 2021 and ~~2019~~fiscal 2022 were as follows:

Named Executive
Officer


2019
Base Salary


2018
Base Salary


Percentage
Adjustment

Christopher Anzalone
President & CEO

   $

682,500

   $

650,000



5

%

Bruce Given
Chief Operating Officer

   $

500,000

   $

455,000



10

%

Kenneth Myszkowski
Chief Financial Officer

   $

430,000

   $

400,000



8

%

Patrick O’Brien
General Counsel

   $

426,400

   $

410,000



4

%

Zhen Li (1)
Senior Vice President
Chemistry &Non-Clinical Development

   $

390,000

   $

300,000



30

%

~~(1)~~

~~Dr. Li’s employment with the Company terminated in February 2019.~~


Named Executive Officer	Fiscal 2022 Base Salary (2)	Fiscal 2022 Base Salary (after July 1, 2022 adjustment)	Fiscal 2021 Base Salary	Percentage Adjustment (3)
Christopher Anzalone President & CEO	$870,350	$870,350	$844,600	3%
Kenneth Myszkowski Chief Financial Officer	$503,928	$529,124	$489,250	8%
Patrick O’Brien Chief Operating Officer and General Counsel	$498,623	$523,554	$484,100	8%
James Hamilton Chief of Discovery and Translational Medicine	$449,904	$472,399	$432,600	9%
Tracie Oliver (1) Chief Commercial Officer	$437,750	$446,250	N/A	N/A

(1)Ms. Oliver joined the Company in June 2022 and the rate shown in column "Fiscal 2022 Base Salary" is her base salary on an annualized basis.

(2)Mr. Myszkowski, Mr. O’Brien, Dr. Hamilton, and Ms. Oliver received a 5% increase in base salary mid-year in accordance with a company-wide inflation and employee retention adjustment. Dr. Anzalone did not receive a mid-year adjustment.

(3)A portion of this percentage increase includes the 5% mid-year company-wide inflation adjustment referred to in footnote 2.

The actual base salaries paid to our ~~Named Executive Officers~~NEOs in fiscal ~~2019~~2022 are set forth in the “Fiscal ~~2019~~2022 Summary Compensation Table” below.

Annual Cash Incentive Compensation

We provide our executive officers, including our ~~Named Executive Officers,~~NEOs, with the opportunity to earn performance-based annual incentive awards, payable in cash, which are designed to reward them for our overall corporate performance as well as their individual performance. Generally, our executive officers are evaluated each year for eligibility to receive an annual cash incentive compensation opportunity. Through a collaborative planning process involving our Board and management, corporate performance objectives are established at the beginning of each year and evaluated regularly by our Board for their continued relevance to our status.

Target Annual Cash ~~Bonus~~Incentive Award Opportunities

For purposes of the ~~2019~~fiscal 2022 performance-based incentive awards, each of our ~~Named Executive Officers~~NEOs was assigned a target annual cash incentive award opportunity based upon a percentage of his or her base salary. The target annual cash incentive award opportunities for our executive officers, including our ~~Named Executive Officers,~~NEOs, were recommended by our CEO (except with respect to his own target annual cash incentive award opportunity) based on each executive officer’s accountability, scope of responsibilities, and potential impact on our performance, and approved by the Compensation Committee. The determination of target annual cash incentive award opportunities was also based on the factors described in “Governance of Executive Compensation Program — Compensation-Setting Process” above. ~~Based on higher levels of control and accountability for~~For our ~~overall performance,~~NEOs other than Ms. Oliver, who joined the Company in June 2022, target annual cash incentive award opportunities did not change from fiscal 2021. In some instances the cash incentive award to our NEOs was a ~~higher percentage of each executive officer’s total~~cash equivalent in common stock.

The target cash ~~compensation was dependent on his or her performance-based annual incentive awards.~~

~~The target~~ annual incentive award opportunities for our ~~Named Executive Officers~~NEOs were as follows:

Named Executive
Officer


2019 Target Annual
Incentive Award
Opportunity (as a
percentage of base
salary)

2018 Target Annual
Incentive Award
Opportunity (as a
percentage of base
salary)

Dr. Anzalone



100

%

100

%

Dr. Given



70

%

70

%

Mr. Myszkowski



45

%

45

%

Mr. O’Brien



45

%

45

%

Dr. Li (1)



40

%

40

%

~~(1)~~

~~Dr. Li’s employment with the Company terminated in February 2019.~~

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2023 PROXY STATEMENT Executive Compensation


Named Executive Officer	Fiscal 2022 Target Annual Incentive Award Opportunity (as a percentage of base salary)	Fiscal 2021 Target Annual Incentive Award Opportunity (as a percentage of base salary)
Dr. Anzalone	100%	100%
Mr. Myszkowski	45%	45%
Mr. O’Brien	45%	45%
Dr. Hamilton	45%	45%
Ms. Oliver (1)	40%	N/A

(1)Ms. Oliver joined the Company in June 2022.

Performance Objectives

In determining the amount of the annual cash incentive award for each of our executive officers, including each of our ~~Named Executive Officers,~~NEOs, the Compensation Committee evaluated the corporate performance objectives that had been established at the beginning of the calendar year (as set forth below) as well as other corporate and individual achievements and performance throughout the year. These performance objectives addressed milestones for our lead products, research and development milestones for our drug pipeline and business development objectives. In December ~~2019,~~2022, the Compensation Committee determined that we had largely achieved or exceeded our primary business objectives set for calendar ~~2019,~~2022, as described below.

~~Goal~~

~~Achievement~~

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2023 PROXY STATEMENT Executive Compensation


Goal		Achievement Highlights
Corporate ~~Development~~ Weight: ~~22%~~ 20% Meet certain goals related to capital formation, market capitalization; board interface with scientific leaders		Met, ~~and Exceeded~~ including some stretch goals Ended ~~year~~fiscal 2022 with ~~a market capitalization of $6.3 billion.~~ ~~Ended year with $533M cash.~~ ~~Developed strategic indication and regulatory plans forARO-APOC3~~ ~~andARO-ANG3~~ ~~Completed a financing~~more than $700 million cash Generated more than $100 million in ~~December 2019 that generated gross~~ ~~proceeds of $266.8 million~~ non-dilutive capital
New Business DevelopmentWeight: 15% Meet certain goals with regard to new pharma collaborations		Met ~~InitiatedJNJ-1~~ ~~program under collaboration agreement with Janssen.~~ ~~Triggered milestone payments under Janssen licensing agreement relating~~ Formed joint venture in China to~~JNJ-3989(ARO-HBV).~~ develop and commercialize certain assets in China; raised more than $50 million for China operations.
Manufacturing Weight: 10% Meet certain requirements pursuant to ~~GMP~~ manufacturing capabilities		Met, ~~GMP facility construction complete.~~ including stretch goals Increased in-house production of clinical drug substance supply by more than 20% Meaningful breakthrough in drug substance process development.
~~Clinical~~ Discovery and Early DevelopmentWeight: 25% Meet certain goals with regard to progress on ~~the Company’s~~ our pre-clinical and early clinical programs		Met, ~~and Exceeded~~ ~~Filed IND for~~including some stretch goals ~~ARO-HIF2~~ ~~Filed CTA for~~ Nomination of a first drug candidate in a not-yet-disclosed new tissue. ~~ARO-HSD~~ ~~(NASH target).~~ ~~Completed enrollment and presented data forARO-ANG3~~ ~~Completed enrollment and presented data for ARO-APOC3~~ ~~Initiated potentially pivotal~~ Achieve target knock-down in non-human primate study for a pulmonary drug ~~ARO-AAT~~ Submit new clinical trial applications for four new studies. Establish pre-clinical proof-of-concept evidence in an entirely new (undisclosed) cell type.
~~Pre-Clinical~~Clinical Development ~~Development~~Weight: ~~14%~~ 25% Meet certain goals relating to Phase 2 and 3 studies in our clinical programs.		Met, ~~except certain~~including some stretch goals ~~Good progress on Company’s discovery and new target projects~~ Complete enrollment for ARO-ANG2 Phase 2 trial Complete ARO-APOC3 sHTG Phase 2 trial Complete enrollment of ARO-APOC3 MD Phase 2 trial Significant number of patients dose in two cardiometabolic trials.
~~Next Generation~~ Early Commercial Weight: ~~14%~~ 5% Meet certain goals for ~~Company’s new~~our early commercial capabilities	~~Met and exceeded~~ ~~Developed muscle- and pulmonary-targeting capability~~ ~~Advanced other significant new capabilities~~


Met 26				Optimize target product profiles for three early clinical programs.

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Annual Incentive Award Payments

The actual annual cash incentive award payments earned by our ~~Named Executive Officers~~incumbent NEOs ranged from ~~130% to 243%~~90%-100% of ~~their~~the respective target ~~annual incentive~~ award opportunities. Except for the annual incentive award for our CEO, these awards were recommended by our CEO and approved by the Compensation Committee based on the overall achievement of ~~the Company’s~~our goals, their contributions to the goals and the overall performance of each executive officer during the year. The following table sets forth the target annual cash incentive award opportunities, the ~~actual~~target award ~~payment~~expressed as a percentage of each ~~Named Executive Officer’s~~NEO’s base salary and the actual award payment made in cash or cash equivalents to each of our ~~Named Executive Officers~~NEOs based on their performance in ~~2019:~~

Named Executive
Officer



Target Annual
Incentive Award
Opportunity (as a
percentage of base
salary)

Actual Annual
Incentive Award
(as a percentage of
base salary)

Actual Annual
Incentive Award
($)

Dr. Anzalone



100

%

226

%

$

1,540,000

Dr. Given



70

%

170

%

$

850,000

Mr. Myszkowski



45

%

59

%

$

251,550

Mr. O’Brien



45

%

59

%

$

249,444

Dr. Li (1)



40

%

0

%

$

0

fiscal 2022:

~~(1)~~	~~Dr. Li’s employment with the Company terminated in February 2019.~~
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2023 PROXY STATEMENT Executive Compensation


Named Executive Officer	Target Annual Incentive Award Opportunity (as a percentage of base salary)	Achievement target bonus	Actual Annual Incentive Award ($)
Dr. Anzalone	100%	90%	$783,315
Mr. Myszkowski	45%	100%	$238,106
Mr. O’Brien	45%	100%	$235,599
Dr. Hamilton	45%	100%	$212,580
Ms. Oliver (1)	40%	100%	$94,874

(1)Ms. Oliver joined the Company in June 2022. Ms. Oliver received 100% of her target bonus, which was pro-rated to 53% of her target annual incentive opportunity based on her hire date.

The annual cash incentive award payments made to our ~~Named Executive Officers~~NEOs for fiscal ~~2019~~2022 are set forth in the “Fiscal ~~2019~~2022 Summary Compensation Table” below.

Long-Term Incentive Compensation

We view long-term incentive compensation in the form of equity awards as a critical element of our executive compensation program. The realizable value of these equity awards over time bears a direct relationship to our stock price, and, therefore, these awards are an incentive for our executive officers, including our ~~Named Executive Officers,~~NEOs, to create value for our stockholders. Equity awards also help us retain qualified executive officers in a competitive market.

Long-term incentive compensation opportunities in the form of equity awards are granted to our executive officers by the Compensation Committee. The amount and forms of such equity awards are determined by the Compensation Committee after considering the factors described in “Governance of Executive Compensation Program — Compensation-Setting Process” above.

~~2019~~

2022 Long-Term Incentive Awards

Performance-Based RSU Award for Chief Executive Officer

Annual equity awards granted to our executive officers are solely in the form of RSU awards that may be settled for shares of our common stock. Our CEO's award was initially designed entirely as a performance-based award. In July of 2022, in response to stockholder feedback and with the ~~case~~consent of Dr. Anzalone, our ~~CEO,~~CEO’s fiscal 2022 compensation was revised to achieve a total, direct compensation equal to the median of his peers. This was achieved by significantly reducing the equity award ~~is entirely performance-based. On~~and re-formulating the equity award to consist 60% of performance-based RSUs and 40% of time-based RSUs. Accordingly, Dr. Anzalone’s revised and recalculated equity award for fiscal 2022 consists of 248,803 RSUs, 40% (99,521) of which are time-based units that vest in four equal installments commencing on January 1, ~~2019, Dr. Anzalone was granted a performance-based RSU (“PRSU”)~~2023, and 60% (149,282) of ~~600,000 shares~~which are PRSU awards to be ~~vested~~earned in three ~~equal~~ installments on the achievement of the following milestones:

~~Achieve market capitalization~~

i.Initiation by the Company of ~~$2 billion~~a Phase 3 clinical study of an investigational drug for a non-orphan indication (49,761 units);

ii.Initiation of a Phase 2 study by the Company or one of its licensees for one of the Company’s non-hepatocyte targeted investigational drugs (49,761 units); and ~~hold for 6 six months;~~

~~File a~~

iii.Achievement of 15 Arrowhead-discovered drugs in clinical ~~trial application~~study or ~~IND for lung- or muscle-targeted candidate;~~clinical use (inclusive of wholly-owned and

out licensed drugs) (49,760 units).

•

~~Mantain 8 TRiM~~^™~~-enabled candidates in the clinic at the same time. Candidates can either be wholly owned or partnered.~~

The performance milestones must be achieved by January 1, ~~2021~~2026 or the ~~grant~~portion of the PRSU tied to each specific milestone will expire.

Each unit granted pursuant to the PRSU award represents a contingent right to receive one share of our common stock for each unit earned prior to the end of the performance period.

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2023 PROXY STATEMENT Executive Compensation

Results from PRSU Awards Previously Granted

~~The~~

In fiscal 2022, the Compensation Committee ~~has~~ certified achievement of the performance milestones ~~and the vesting of~~relating to the following ~~PRSUs granted to our CEO.~~

PRSU awards:

Performance Goal

Achievement

N~~No.~~o. of Shares

Certified as Vested

Achieve ~~market capitalization~~the largest active clinical pipeline of ~~$2 billion and hold for six months~~

~~Granted~~RNAi therapeutics

Issued 01/~~01/2019~~

2020

Certified ~~on 12/6/2019~~

in October 2021

~~200,000~~

100,000 shares pursuant to a PRSU award

~~Initiate a study that could be pivotal or meet criteria that big pharma would consider to be~~

Complete Sequoia enrollment and maintain leadership in the field

~~proof-of-concept~~

~~Granted~~

Issued 01/~~01/2018~~

2020

Certified ~~on 12/6/2019~~

in December 2021

~~166,666~~

100,000 shares pursuant to a PRSU award

~~Execute a business development transaction for a target outside hepatocytes~~

~~Granted 1/1/2018~~

~~The compensation committee deemed this performance goal to be met on 12/22/2019 as the intent of the performance goal was substantially met.~~

~~166,667 shares pursuant to a PRSU award~~

~~Achieve $1 billion market capitalization and hold for 2 quarters~~

~~Granted 1/1/2016~~

~~Achieved on 12/18/2018~~

~~180,000 shares pursuant to a PRSU award~~

~~File an IND or equivalent for an extra-hepatic target~~

~~Granted 1/1/2016~~

~~The Compensation Committee deemed this completed on 12/11/2018, given that the Company could have filed an IND for an extra-hepatic target, but chose to delay this filing for strategic purposes~~

~~180,000 shares pursuant to a PRSU award~~

~~Execute a significant business development transaction by 12/31/2019~~

~~Granted 4/12/2017~~

~~Janssen collaboration~~

~~163,000 shares pursuant to a PRSU award~~

~~Equity~~

RSU Awards for Other Named Executive Officers

The Compensation Committee approved the following aggregate ~~equity~~RSU awards for our ~~Named Executive Officers~~other NEOs for ~~2019:~~

Named Executive
Officer


Restricted Stock Unit
Awards
(number of shares)


Restricted Stock Unit
Grant Date Fair Values
($)

Mr. Given



210,000

   $

2,608,200

Mr. Myszkowski



85,000

   $

1,055,700

Mr. O’Brien



70,000

   $

869,400

Dr. Li (1)



75,000

   $

931,500

~~(1)~~

~~Dr. Li’s employment with the Company terminated in February 2019.~~


28

2022:


Named Executive Officer	Restricted Stock Unit Awards (number of shares)	Restricted Stock Unit Awards ($)
Mr. Myszkowski	60,000	$3,978,000
Mr. O’Brien	60,000	$3,978,000
Dr. Hamilton	55,000	$3,646,500
Ms. Oliver (1)	70,000	$2,517,200

~~2020 PROXY STATEMENT~~
~~Executive Compensation~~

~~The awards~~

RSUs granted to our NEOs in fiscal 2022 vest over 4four years in 4 equal ~~installments.~~

annual installments, subject to the NEO’s continued employment on each applicable vesting date.

The equity awards granted to our ~~Named Executive Officers~~NEOs in fiscal ~~2019~~2022 are set forth in the “Fiscal ~~2019~~2022 Summary Compensation Table” and the “Fiscal ~~2019~~2022 Grants of Plan-Based Awards Table” below.

Welfare and Health Benefits

Our executive officers, including our ~~Named Executive Officers,~~NEOs, are eligible to participate in all of our employee benefit plans, including medical, dental, vision, life and disability insurance, in each case on the same basis as our other employees, subject to applicable law. In addition, we provide an additional life insurance ~~for~~benefit to our CEO for the benefit of his heirs. We also provide vacation and other paid holidays to all our employees, including our executive officers, all of which we believe to be comparable to those provided atthe companies in our compensation peer ~~companies.~~group. These benefit programs are designed to enable us to attract and retain our workforce in a competitive marketplace. Our health, welfare and vacation benefits are designed to ensure that we have a productive and focused workforce through reliable and competitive health and other benefits.

Our retirement savings plan (“401(k) ~~plan~~”plan”) is atax-qualified retirement savings plan, pursuant to which qualified employees, including our ~~Named Executive Officers,~~NEOs, are able to contribute certain amounts of their annual compensation, subject to limits prescribed by the Internal Revenue Service. Historically, we have made matching contributions of 100% of the first 3% of base salary and of 50% of the next 2% of base salary contributed to the plan. The value of these benefits for each of our ~~Named Executive Officers~~NEOs is reflected in the “All Other Compensation” column of the ~~“Summary~~“Fiscal 2022 Summary Compensation Table” below.


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2023 PROXY STATEMENT Executive Compensation

Perquisites and Other Personal Benefits

Currently, we do not view perquisites or other personal benefits as a significant component of our executive compensation program. Accordingly, we do not provide significant perquisites or other personal benefits to our executive officers, including our ~~Named Executive Officers,~~NEOs, except as generally made available to our employees, or in situations where we believe it is appropriate to assist an individual in the performance of his or her duties, to make our executive officers more efficient and effective and for recruitment and retention purposes.

In the future, we may provide perquisites or other personal benefits in limited circumstances, such as those described in the preceding paragraph. All future practices with respect to perquisites or other personal benefits will be approved and subject to periodic review by the Compensation Committee.

Employment Arrangements

We have entered into a written employment agreement with our CEO and have written employment offer letters with our other executive officers.In filling each of our executive positions, we recognized the need to develop competitive compensation packages to attract qualified candidates in a dynamic labor market. At the same time, in formulating these compensation packages, we were sensitive to the need to integrate new executive officers into the executive compensation structure that we were seeking to develop, balancing both competitive and internal equity considerations. Each of these arrangements provides for “at will” employment.

For detailed descriptions of the employment arrangements we maintained with our ~~Named Executive Officers for 2019,~~NEOs during fiscal 2022, see “Termination Benefits — Potential Payments Upon Termination or Change in Control” below.

Post-Employment Compensation Arrangements

We have entered into ana written employment agreement with our CEO, and we also have agreements with our CFO and Chief Operating and General Counsel that provide for certain payments and benefits in the event of certain involuntary terminations of employment. We believe that having in place reasonable and competitive post-employment compensation arrangements are essential to attracting and retaining highly-qualified executive officers. These agreements are designed to provide reasonable compensation these to executive officers ~~who~~if they were to leave our employ under certain circumstances to facilitate their transition to new employment. Further, in some instances we seek to mitigate any potential employer liability and avoid future disputes or litigation by requiring a departing executive officer to sign a separation and release agreement acceptable to us as a condition to receiving post-employment compensation payments or benefits.

The Compensation Committee does not consider the specific amounts payable under these agreements when establishing annual compensation. We do believe, however, that these arrangements are necessary to offer compensation packages that are competitive.


					29

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

In addition, our 2013 Incentive Plan and our 2021 Incentive Plan each provides for the acceleration of vesting of outstanding and unvested equity awards in the event of a change in control of the Company, as defined in the ~~plan,~~plans, except as otherwise determined by our Board. ~~The Company has amended~~However, the agreements for ~~outstanding~~ equity awards granted to our CEO pursuant to our ~~2004 Equity~~2013 Incentive Plan and ~~2013~~our 2021 Incentive Plan to provide that, upon a change in control of the Company, the vesting of such awards will accelerate only in the event of a subsequent involuntary termination of employment (a “double-trigger” arrangement).

For detailed descriptions of the post-employment compensation arrangements we maintained with our ~~Named Executive Officers for 2019,~~NEOs during fiscal 2022, as well as an estimate of the potential payments and benefits payable under these arrangements, see “Termination Benefits — Potential Payments Upon Termination or Change in Control” below.

Other Compensation Policies and Practices

Equity Awards Grant Policy

We do not have any program, plan, or obligation that requires us to grant equity awards on specified dates, although historically we have granted such awards to our existing executive officers and employees at least annually and to newly-hired employees onupon the commencement of their employment. We do not have any program, plan or practice to grant ~~options to purchase shares~~equity awards of our common stock to our executive officers in coordination with the release of material


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2023 PROXY STATEMENT Executive Compensation

nonpublic information. Equity awards may occasionally be granted following a significant change in job responsibilities or to meet other special retention or performance objectives.

Authority to grant equity awards to our employees rests with the Compensation Committee, although the Compensation Committee has delegated authority to our CEO to grant equity awards tonon-executive employees within prescribed limits set by the Compensation Committee. With respect to our executive officers, except for our CEO, recommendations for equity awards are made by our CEO and reviewed and approved by the Compensation Committee.

Under the terms of our ~~2013~~2021 Incentive Plan, pursuant to which new equity awards are granted, the exercise price of any option to purchase shares of our common stock awarded under the plan must be equal to at least 100% of the fair market value of our common stock (which is determined based on the closing sales price of our common stock on the Nasdaq Global Market) on the date of grant.

Stock Ownership Policy

We maintain a stock ownership policy for our CEO ~~COO,~~ and CFO to further align their respective interests with the interests of our stockholders, and to further promote our commitment to sound corporate governance. This policy requires our CEO to own a minimum number of shares of our common stock equal to a value of six times his annualized base salary and our ~~COO and~~ CFO to own a minimum number of shares of our common stock equal to a value of twice ~~their~~his annualized base salary. ~~Each of these executive officers has~~Our CEO and CFO have each achieved the respective required ~~ownership.~~

ownership level.

Compensation Recovery (“Clawback”) Policy

In December 2017, our Board adopted a compensation recovery (“clawback”) policy as follows:

“If Arrowhead Pharmaceuticals, Inc. (the “Company”) is required to materially restate any of its financial statements, the Board of Directors (the “Board”) shall assess the degree to which any fraud, negligence, or intentional misconduct by any executive officer of the Company was responsible for such restatement. If the Board determines that any executive officer was responsible for causing such restatement, the Board shall, in addition to any other lawful remedies the Board or the Company may take, seek recovery of all or a portion of the incentive compensation awarded to the executive officer for the performance period covered by the restated financial statement, provided that such recovery shall not extend to payments made more than three years prior to the date the financial record was restated. In addition, the Board may, in its absolute discretion, revoke any of the responsible executive officer’s unpaid or unvested incentive compensation outstanding as of the date of the Board’s determination of the executive officer’s responsibility for the financial restatement.”

In addition, our 2013 Incentive Plan and our 2021 Incentive Plan each provides for the recovery of awards made under the plan in accordance with any applicable compensation recovery or recoupment policy, including as required by law, regulation or national securities exchange rule.


30

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Policy Prohibiting Hedging and Limiting Pledging

Our Insider Trading Policy prohibits our employees, ~~including~~ our executive officers, and thenon-employee members of our Board from short-term trading, options trading, trading on margin, pledging our common stock as collateral, and all hedging transactions with respect to our securities, except ~~for pledging~~our board members and executive officers may pledge up to 50% owned and vested stock as collateral for a loan subject to the approval of ~~the~~our Board.

Tax and Accounting Considerations

Deductibility of Executive Compensation

~~Prior to the US Tax Cuts and Jobs Act enacted in December of 2017 (the “~~~~US Tax Act~~~~”), compensation that satisfied conditions set forth under~~

Section 162(m) of the Internal Revenue Code ~~to qualify as “performance-based compensation” was not subject to a $1 million limit on~~limits the federal income tax deductibility ~~and the limit did not apply to~~of certain compensation paid to the Chief Financial Officer. The US Tax Act eliminates the performance-based compensation exception and applies the limit to the Chief Financial Officer and certain former executive officers. However, it provides a transition rule with respect to remuneration provided under a written contract which was in effect on November 2, 2017 and which was not materially modified after that date. With eliminating the exemption for performance-based compensation, we expect that we will be unable to deduct all compensationamounts in excess of $1 million paid to our Chief Executive Officer, Chief Financial Officer and our other Named Executive Officers covered by the new tax law, other than previously granted awards that comply with the transition rules. We monitor the application of Section 162(m) and the associated Treasury regulations on an ongoing basis and the advisability of qualifyingcertain executive ~~compensation for deductibility. Notwithstanding the repeal of the exemption for “performance-based compensation,”~~officers. While the Compensation Committee ~~intends~~generally seeks to ~~maintain its commitment~~pay compensation that is tax-deductible, it reserves the right to ~~structuring~~pay non-deductible compensation to the ~~Company’s executive compensation programs in a manner designed to align pay with performance.~~

extent it deems appropriate.


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Accounting for Stock-Based Compensation

We follow the Financial Accounting Standard Board’s Accounting Standards Codification Topic 718 (“FASB ASC Topic ~~718~~”718”) for our stock-based compensation awards. FASB ASC Topic 718 requires us to measure the compensation expense for all share-based payment awards made to our employees andnon-employee members of our Board, including options to purchase shares of our common stock and other stock awards, based on the grant date “fair value” of these awards. This calculation is performed for accounting purposes and reported in the executive compensation tables required by the federal securities laws, even though the recipient of the awards may never realize any value from their awards.

~~2020~~Table of Contents

2023 PROXY STATEMENT Executive Compensation

Compensation Risk Assessment

In reviewing our various compensation programs, the Compensation Committee considers how our compensation policies and practices may affect our risk profile and whether such policies and practices may encourage undue risk-taking by our employees. More specifically, the Compensation Committee considers the general design philosophy of our policies and practices for our employees whose conduct would be most affected by incentives established pursuant to these compensation policies. In considering these issues, the Compensation Committee concluded that the use of a performance-based annual incentive compensation plan and long-term incentive compensation opportunities in the form of equity awards did not appear to create undue risks for us or encourage excessive risk-taking behavior on the part of our ~~Named Executive Officers.~~

NEOs.

With respect to the annual incentive awards for our executive officers, the amount of an individual’s award depends principally on overall Company performance, as determined by the Compensation Committee, which reduces the ability and incentive for an individual to take undue risks at the expense of our performance in an effort to increase the amount of his or her annual incentive award. Our performance objectives are reviewed regularly by the Compensation Committee and our Board and are considered to be generally of the nature that promote the steady progression of our development programs and would not encourage or reward excessive risk-taking. In addition, our Board has the ability to intervene in instances where actions by our executive officersvis-à-vis Company performance objective attainment would be considered unduly risky to prevent or penalize such actions.

Compensation Committee Report

The Compensation Committee of the Company has reviewed and discussed with management the Compensation Discussion and Analysis required by Item 402(b) ofRegulation S-K. Based on this review and discussion, the Compensation Committee recommended to ~~the~~our Board that the foregoing Compensation Discussion and Analysis be included in this proxy statement.

Submitted by the Compensation

Committee of the Board of Directors

~~Michael S. Perry, Chairman~~

William Waddill, Committee Chair

Marianne De Backer

Mauro Ferrari

~~William Waddill~~


32

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Adeoye Olukotun

Michael Perry

Compensation Committee Interlocks and Insider Participation

During ~~2019,~~2022, Dr. Perry, Dr. De Backer, Dr. Ferrari, Dr. Olukoton and Mr. Waddill served on the Compensation Committee. During fiscal year ~~2019~~2022 and through December ~~2019,~~2022, there were no compensation committee interlocks between the Company and other entities involving the Company’s executive officers and directors.


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Fiscal 2022 Summary Compensation Table

The following table summarizes compensation earned for services rendered during fiscal ~~2019, 2018,~~2022, 2021, and ~~2017~~2020 by our Chief Executive Officer, our Chief Financial Officer, our Chief Operating Officer ~~our~~and General Counsel, our Chief of Discovery and Translational Medicine, and our ~~Senior Vice President of Chemistry andNon-Clinical~~ ~~Development,~~Chief Commercial Officer, collectively our “Named Executive Officers”:

Name and
Principal Position    Year    Salary
($)
Stock
Awards (1)
($)

Non-Equity
Incentive Plan
Compensation (2)
($)

All Other
Compensation (3)
($)
   Total

Christopher Anzalone

President and Chief
Executive Officer



2019



674,375



—

(4)

1,540,000



1,889



2,216,264



2018



643,012



—

(5)

975,000



1,889



1,619,901



2017



616,068



537,900

(6)

715,357



1,889



1,871,214

Kenneth Myszkowski
Chief Financial Officer



2019



422,500



1,055,700

251,550



11,799



1,741,549



2018



384,841



276,000

180,000



12,177



853,018



2017



336,099



224,750

152,713



11,809



725,371

Bruce D. Given

Chief Operating Officer



2019



488,750



2,608,200

850,000



11,799



3,958,759



2018



450,362



644,000

445,900



11,799



1,552,061



2017



432,250



589,000

351,340



11,599



1,384,189

Patrick O’Brien

General Counsel



2019



422,300



869,400

249,444



11,799



1,552,943



2018



406,196



220,800

184,500



11,799



823,295



2017



390,988



224,750

177,653



11,599



804,990

Zhen Li (7)
Senior Vice President,
Chemistry and Non-
Clinical Development


2019



150,257



931,500

—



4,236



1,085,993



2018



287,462



239,200

150,000



9,462



686,124



2017



247,448



131,750

120,000



6,798



505,996


Name and Principal Position	Year	Salary ($)	Bonus (S)	Stock Awards (1) ($)		Non-Equity Incentive Plan Compensation (2) ($)	All Other Compensation (3) ($)	Total
Christopher Anzalone	2022	863,417	—	10,382,549	(4)	783,315	355	12,029,636
President and Chief Executive Officer	2021	837,031	—	23,019,000	(5)	845,000	2,824	24,703,855
	2020	785,625	—	12,686,000	(6)	820,000	2,892	14,294,517
Kenneth Myszkowski	2022	509,648	—	3,978,000		238,106	12,555	4,738,309
Chief Financial Officer	2021	484,865	—	4,603,800		231,171	13,734	5,333,570
	2020	463,750	—	5,391,550		213,750	12,802	6,081,852
Patrick O’Brien	2022	500,466	—	3,978,000		235,599	12,555	4,726,620
Chief Operating Officer and General Counsel	2021	479,762	—	4,603,800		239,630	13,734	5,336,926
	2020	459,100	—	4,440,100		211,500	12,802	5,123,502
James Hamilton	2022	450,436	—	3,646,500		212,580	12,555	4,322,071
Chief of Discovery and Translational Medicine	2021	426,109	—	3,836,500		233,604	13,734	4,509,947
	2020	376,362	—	2,854,350		169,363	12,802	3,412,877
Tracie Oliver (7)	2022	111,154	16,344	2,517,200		94,874	4,505	2,744,077
Chief Commercial Officer	2021	—	—	—		—	—	—
	2020	—	0	—		—	—	—

(1)These columns represent the total grant date fair value, computed in accordance with ASC 718, of restricted stock units granted during fiscal year 2022, 2021 and 2020. The assumptions used to calculate the value of the stock underlying the restricted stock unit awards are set forth in Note 9 of the Notes to the Consolidated Financial Statements included with the Company’s Annual Report on Form 10-K.

(2)These bonus amounts represent the amounts earned for performance under the Company’s Annual Bonus Incentive Plan during calendar year 2022, 2021 and 2020 and paid in fiscal year 2023, 2022 and 2021, respectively. The Annual Bonuses are described in more detail in the “Bonus Incentive” section.

(3)Amounts consist of 401(k) matching contribution, as well as life insurance premiums for the benefit of each executive officer.

(4)In July of 2022, our CEO’s fiscal 2022 compensation was revised by reducing his equity award and re-formulating the equity award to consist 60% of performance-based RSUs and 40% of time-based RSUs. The CEO's Stock Awards are described in more detail in the "Our CEO’s Fiscal 2022 Equity Award"section. The amounts reported for Christopher Anzalone in the Stock Awards column reflect the grant date fair value of a July 2022 restricted stock unit award that is subject to vesting upon the achievement of specific performance conditions, as described above in the Compensation Discussion and Analysis. We determined the performance conditions that were probable and not probable of being achieved as of the grant date, as defined under applicable accounting guidance, and assigned a grant date fair value of $6,229,538 based on this evaluation. The amounts reported in the Summary Compensation Table for these awards may not represent the amounts that Christopher Anzalone will realize from the awards. Whether, and to what extent, an NEO realizes value will depend on our actual operating performance, stock price fluctuations and the NEO’s continued employment.

~~(1)~~

This column represents the total grant date fair value, computed in accordance with ASC 718, of restricted stock units granted during fiscal year 2019, 2018 and 2017. The assumptions used to calculate the value of the stock underlying the option and restricted stock unit awards are set forth in Note 8 of the Notes to the Consolidated Financial Statements included with the Company’s Annual Report on~~Form 10-K.~~

~~(2)~~

These bonus amounts represent the amounts earned for performance under the Company’s Annual Bonus Incentive Plan during calendar year 2019, 2018 and 2017 and paid in fiscal year 2020, 2019 and 2018, respectively. The Annual Bonuses are described in more detail in the “Bonus Incentive” section.

~~(3)~~

~~Amounts consist of 401(k) matching contribution, as well as life insurance premiums for the benefit of each executive officer.~~

~~(4)~~

The amounts reported for Christopher Anzalone in the Stock Awards column reflect the grant date fair value of a January 2019 restricted stock unit award that is subject to vesting upon the achievement of specific performance conditions, as described above in the Compensation Discussion and Analysis. We determined the performance conditions that were probable and not probable of being achieved as of the grant date, as defined under applicable accounting guidance, and assigned a grant date fair value of $0 based on this evaluation. If we had determined that as of the date of the grant it was probable that 100% of the performance conditions would be achieved, we would have assigned a grant date fair value of $7,452,000 for the restricted stock units. The amounts reported in the Summary Compensation Table for these awards may not represent the amounts that Christopher Anzalone will realize from the awards. Whether, and to what extent, a named executive officer realizes value will depend on our actual operating performance, stock price fluctuations and the named executive officer’s continued employment.

~~(5)~~

The amounts reported for Christopher Anzalone in the Stock Awards column reflect the grant date fair value of a January 2018 restricted stock unit award that is subject to vesting upon the achievement of specific performance conditions, as described above in the Compensation Discussion and Analysis. We determined the performance conditions that were probable and not probable of being achieved as of the grant date, as defined under applicable accounting guidance, and assigned a grant date fair value of $0 based on this evaluation. If we had determined that as of the date of the grant it was probable that 100% of the performance conditions would be achieved, we would have assigned a grant date fair value of $1,840,000 for the restricted stock units. The amounts reported in the

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2023 PROXY STATEMENT Executive Compensation

(5)The amounts reported for Christopher Anzalone in the Stock Awards column reflect the grant date fair value of a January 2021 restricted stock unit award that is subject to vesting upon the achievement of specific performance conditions, as described above in the Compensation Discussion and Analysis. We determined the performance conditions that were probable and not probable of being achieved as of the grant date, as defined under applicable accounting guidance, and assigned a grant date fair value of $23,019,000 based on this evaluation. If we had determined that as of the date of the grant it was probable that 100% of the performance conditions would be achieved, we would have assigned a grant date fair value of $61,384,000 for the restricted stock units. The amounts reported in the Summary Compensation Table for these awards may not represent the amounts that Christopher Anzalone will realize from the awards. Whether, and to what extent, an NEO realizes value will depend on our actual operating performance, stock price fluctuations and the NEO’s continued employment. Additionally, in December 2021, these awards were modified to change the vesting to be subject entirely based on market capitalization-based thresholds rather than performance conditions. This modification did not result in any incremental fair value associated with the award.

(6)The amounts reported for Christopher Anzalone in the Stock Awards column reflect the grant date fair value of a January 2020 restricted stock unit award that is subject to vesting upon the achievement of specific performance conditions, as described above in the Compensation and Analysis. We determined the performance conditions that were probable and not probable of being achieved as of the grant date, as defined under applicable accounting guidance, and assigned a grant date fair value of $12,686,000 based on this evaluation. If we had determined that as of the date of the grant it was probable that 100% of the performance conditions would be achieved, we would have assigned a grant date fair value of $57,087,000 for the restricted stock units. The amounts reported in the Summary Compensation Table for these awards may not represent the amounts that Christopher Anzalone will realize from the awards. Whether, and to what extent, an NEO realizes value will depend on our actual operating performance, stock price fluctuations and the NEO’s continued employment.

(7)Ms. Oliver's employment with us began in June 2022.

	Summary Compensation Table for these awards may not represent the amounts that Christopher Anzalone will realize from the awards. Whether, and to what extent, a named executive officer realizes value will depend on our actual operating performance, stock price fluctuations and the named executive officer’s continued employment.
						45

~~(6)~~

The amounts reported for Christopher Anzalone in the Stock Awards column reflect the grant date fair value of an April 2017 restricted stock unit award that is subject to vesting upon the achievement of specific performance conditions. We determined the performance conditions that were probable and not probable of being achieved as of the grant date, as defined under applicable accounting guidance, and assigned a grant date fair value of $537,900 based on this evaluation. If we had determined that as of the date of the grant it was probable that 100% of the performance conditions would be achieved, we would have assigned a grant date fair value of $1,613,700 for the restricted stock units. The amounts reported in the Summary Compensation Table for these awards may not represent the amounts that Christopher Anzalone will realize from the awards. Whether, and to what extent, a named executive officer realizes value will depend on our actual operating performance, stock price fluctuations and the named executive officer’s continued employment.

~~(7)~~

~~Dr. Li’s employment with the Company terminated in February 2019.~~

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2023 PROXY STATEMENT Executive Compensation

Fiscal 2022 Grants of Plan Based Awards Table

The following table sets forth cash bonus and equity grants made to the ~~named executive officers~~NEOs in fiscal ~~2019:~~

            Estimated Future Payouts
UnderNon-Equity
Incentive Plan Awards (1)

Estimated
Future Payouts
Under Equity
Incentive Plan
Awards (2)
   All Other Stock
Awards: Number
of Shares of
Stock or Units
(#) (3)
Grant
Date Fair
Value
Name
   Grant Date
Target

Target

Christopher Anzalone



Cash Bonus


$

682,500



—



—

—

PRSUs (4)



1/1/2019



—



200,000



—

—

PRSUs (4)



1/1/2019



—



200,000



—

—

PRSUs (4)



1/1/2019



—



200,000



—

—

Kenneth Myszkowski



Cash Bonus


$

193,500



—



—

—

RSUs



1/1/2019



—



—



85,000

$

1,055,700

Bruce D. Given



Cash Bonus


$

350,000



—



—

—

RSUs



1/1/2019



—



—



210,000

$

2,608,200

Patrick O’Brien



Cash Bonus


$

191,880



—



—

—

RSUs



1/1/2019



—



—



70,000

$

869,400

Zhen Li



Cash Bonus


$

156,000



—



—

—

RSUs



1/1/2019



—



—



75,000

$

931,500

2022:


		Estimated Future Payouts Under Non-Equity Incentive Plan Awards (1)	Estimated Future Payouts Under Equity Incentive Plan Awards (2)	All Other Stock Awards: Number of Shares of Stock or Units (#) (3)	Grant Date Fair Value
Name	Grant Date	Target	Target
Christopher Anzalone
Cash Bonus		$870,350	—	—	—
RSUs	7/8/2022	—	99,521	—	$4,153,011
PRSUs	7/8/2022	—	149,282	—	$6,229,538
Kenneth Myszkowski
Cash Bonus		$226,768	—	—	—
RSUs	1/1/2022	—	—	60,000	$3,978,000
Patrick O’Brien
Cash Bonus		$224,380	—	—	—
RSUs	1/1/2022	—	—	60,000	$3,978,000
James Hamilton
Cash Bonus		$202,457	—	—	—
RSUs	1/1/2022	—	—	55,000	$3,646,500
Tracie Oliver(4)
Cash Bonus		$175,100	—	—	—
RSUs	7/1/22	—	—	70,000	2,517,200

(1)Amounts listed represent cash award targets for our NEOs in fiscal 2022. Actual payments were made in fiscal 2023 and the amounts are reported in the Summary Compensation Table above. There are no thresholds or maximum levels applicable under our annual cash incentive awards.

(2)These RSU and PRSU are described above in the “Compensation Discussion and Analysis” under the heading “Equity Compensation”.

(3)RSUs granted in fiscal 2022 vest in four equal annual installments beginning 1 year from the grant date.

(4)Ms. Oliver’s employment with us began in June 2022. Under her fiscal 2022 compensation arrangements, Ms. Oliver had the opportunity to receive an incentive cash bonus of 40% of her base salary.

~~(1)~~

Amounts listed represent cash award targets for our named executive officers in 2019. Actual payments were made in fiscal 2020 and the amounts are reported in the Summary Compensation Table above. There are no thresholds or maximum levels for such awards.

~~(2)~~

~~These RSU and PRSU awards are described above in the “Compensation Discussion and Analysis” under the heading “Equity Compensation”.~~

~~(3)~~

~~RSUs have various vesting parameters. The RSUs granted in 2019 vest in four equal annual installments beginning 1 year from the grant date.~~

~~(4)~~

We determined that as of the date of the grant it was not probable as defined under applicable accounting guidance that any of the performance vesting conditions for these PRSU awards would be achieved and assigned a grant date fair value of $0 based on this evaluation.


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Fiscal 2022 Outstanding Equity Awards at Fiscal Year End Table

The following table provides information, with respect to the ~~Named Executive Officers,~~NEOs, concerning the outstanding equity awards covering shares of the Company’s common stock as of September 30, ~~2019.~~

      Option Awards          Stock Awards
Name
Grant
Date
Number of
Securities
Underlying
Unexercised
Options (#
Exercisable)
(1) Number of
Securities
Underlying
Unexercised
Options (#
Unexercisable) Option
Exercise
Price ($) Option
Expiration
Date
Number of
Shares or
Units of
Stock
That
Have Not
Vested
(#) (3)

Market
Value of
Shares or
Units of
Stock
That
Have
Not
Vested
($) (4)

Equity
Incentive
Plan
Awards:
Number of
Unearned
Shares or
Units of
Stock
That
Have
Not
Vested
(#) (2)

Equity
Incentive
Plan
Awards:
Market
Value
of
Unearned
Shares or
Units of
Stock
That
Have
Not
Vested
($) (4)

  Christopher Anzalone
3/4/2010 56,325 — 5.20 3/4/2020 — — — —
8/16/2010 50,000 — 9.90 8/16/2020 — — — —
10/21/2011 15,000 — 4.60 10/21/2021 — — — —
2/16/2012 170,000 — 5.19 2/16/2022 — — — —
9/28/2012 40,624 — 2.62 9/28/2022 — — — —
5/6/2013 159,928 — 2.01 5/6/2023 — — — —
9/21/2013 69,991 — 4.75 9/21/2023 — — — —
2/6/2014 60,000 — 14.54 2/6/2024 — — — —
3/6/2015 300,000 — 7.75 3/6/2025 — — — —
1/1/2016 73,333 6,667 6.15 1/1/2026 — — — —
1/1/2018 — — — — — — 333,333 6,389,994
1/1/2019 — — — — — — 600,000 16,908,000

  Kenneth Myszkowski
8/16/2010 12,000 — 9.90 8/16/2020 — — — —
2/16/2012 48,000 — 5.19 2/16/2022 — — — —
2/6/2014 50,000 — 14.54 2/6/2024 — — — —
3/6/2015 50,000 — 7.75 3/6/2025 — — — —
1/1/2016 36,666 3,334 6.15 1/1/2026 — — — —
1/1/2018 — — — — 56,250 1,585,125 — —
1/1/2019 — — — — 85,000 2,395,300 — —

  Bruce D. Given
10/26/2011 30,000 — 5.20 10/26/2021 — — — —
2/16/2012 110,000 — 5.19 2/16/2022 — — — —
9/21/2013 40,000 — 4.75 9/21/2023 — — — —
2/6/2014 50,000 — 14.54 2/6/2024 — — — —
3/6/2015 60,000 — 7.75 3/6/2025 — — — —
1/1/2016 55,000 5,000 6.15 1/1/2026 — — — —
1/1/2018 — — — — 131,250 3,698,625 — —
1/1/2019 — — — — 210,000 5,917,800 — —

  Patrick O’Brien
12/2/2014 90,000 — 5.22 12/2/2024 — — — —
1/1/2016 55,000 5,000 6.15 1/1/2026 — — — —
1/1/2018 — — — — 45,000 1,268,100 — —
1/1/2019 — — — — 70,000 1,972,600 — —

  Zhen Li (5)
— — — — — — — — —

2022.


		Option Awards				Stock Awards
Name	Grant Date	Number of Securities Underlying Unexercised Options (# Exercisable) (1)	Number of Securities Underlying Unexercised Options (# Unexercisable)	Option Exercise Price ($)	Option Expiration Date	Number of Shares or Units of Stock That Have Not Vested (#) (3)	Market Value of Shares or Units of Stock That Have Not Vested ($) (4)	Equity Incentive Plan Awards: Number of Unearned Shares or Units of Stock That Have Not Vested (#) (2)	Equity Incentive Plan Awards: Market Value of Unearned Shares or Units of Stock That Have Not Vested ($) (4)
Christopher Anzalone	5/6/2013	104,928	—	2.01	5/6/2023	—	—	—	—
	9/21/2013	57,755	—	4.75	9/21/2023	—	—	—	—
	2/6/2014	57,499	—	14.54	2/6/2024	—	—	—	—
	3/6/2015	300,000	—	7.75	3/6/2025	—	—	—	—
	1/1/2016	51,726	—	6.15	1/1/2026	—	—	—	—
	1/1/2020	—	—	—	—	—	—	900,000	29,745,000
	1/1/2021	—	—	—	—	—	—	800,000	26,440,000
	7/8/2022	—	—	—	—	—	—	248,803	8,222,939
Kenneth Myszkowski	1/1/2019	—	—	—	—	21,250	702,313	—	—
	1/1/2020	—	—	—	—	42,500	1,404,625	—	—
	1/1/2021	—	—	—	—	45,000	1,487,250	—	—
	1/1/2022	—	—	—	—	60,000	1,983,000	—	—
Patrick O’Brien	1/1/2019	—	—	—	—	17,500	578,375	—	—
	1/1/2020	—	—	—	—	35,000	1,156,750	—	—
	1/1/2021	—	—	—	—	45,000	1,487,250	—	—
	1/1/2022	—	—	—	—	60,000	1,983,000	—	—
James Hamilton	1/1/2019	—	—	—	—	15,000	495,750	—	—
	1/1/2020	—	—	—	—	22,500	743,625	—	—
	1/1/2021	—	—	—	—	37,500	1,239,375	—	—
	1/1/2022	—	—	—	—	55,000	1,817,750
Tracie Oliver	7/1/2022	—	—	—	—	70,000	2,313,500	—	—

(1)Options are priced at the market closing price on the date of grant. Options have various vesting parameters, but generally vest within 48 months after the award is granted.

(2)The amounts reported for Christopher Anzalone in this column reflect the January 2020, January 2021, and July 2022 awards that contain performance-based vesting conditions. These awards and their vesting conditions are described above in the “Compensation Discussion and Analysis” under the heading “Equity Compensation”.

~~(1)~~

~~Options are priced at the market closing price on the date of grant. Options have various vesting parameters, but generally vest within 48 months after the award is granted.~~

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2023 PROXY STATEMENT Executive Compensation

(3)Restricted stock units have various vesting parameters but generally vest in four equal annual installments beginning 1 year from the grant date.

(4)Value is based on our Company’s Common Stock closing price of $33.05 on September 30, 2022.

~~(2)~~	The amounts reported for Christopher Anzalone in this column reflect the January 2018 and January 2019 awards that contain performance-based vesting conditions. These awards and their vesting conditions are described above in the “Compensation Discussion and Analysis” under the heading “Equity Compensation”.
						48

~~(3)~~

~~Restricted stock units have various vesting parameters but generally vest in four equal annual installments beginning 1 year from the grant date.~~

~~(4)~~

~~Value is based on the Company’s Common Stock closing price of $28.18 on September 30, 2019.~~

~~(5)~~

~~Dr. Li’s employment with the Company terminated in February 2019.~~

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2023 PROXY STATEMENT Executive Compensation

Fiscal 2022 Options ~~Exercised~~Exercises and Stock Vested Table

The following table provides information, with respect to the ~~Named Executive Officers,~~NEOs, concerning options exercised or RSUs or PRSUs vested during fiscal ~~2019.~~

      Option Awards    Stock Awards
Name

Number of Shares
Acquired on
Exercise
   Value Realized on
Exercise (1)    Number of Shares
Acquired on
Vesting
Value Realized on
Vesting (2)

Christopher Anzalone


162,098


3,723,993


523,000

$
7,425,050

Kenneth Myszkowski


43,000


759,456


180,417

$
2,602,667

Bruce D. Given


206,000


3,528,708


473,750

$
6,429,238

Patrick O’Brien


—


—


160,000

$
2,323,200

Zhen Li


146,041


1,331,278


101,250

$
1,439,775

~~(1)~~

~~Value is calculated as the price of the Company’s Common Stock upon exercise, less the exercise price, multiplied by the number of shares exercised.~~

~~(2)~~

~~Value is calculated as the price of the Company’s Common Stock upon vesting, multiplied by the number of shares vested.~~

2022.

Option Awards Stock Awards
Name

Number of Shares
Acquired on
Exercise
Value Realized on
Exercise (1) Number of Shares
Acquired on
Vesting
Value Realized on
Vesting (2)
Christopher Anzalone 228,125 $ 996,462.00 200,000 $ 13,534,000.00
Kenneth Myszkowski — — 76,250 $ 4,959,300.00
Patrick O’Brien 28,000 $ 172,200.00 65,000 $ 4,227,600.00
James Hamilton — — 51,250 $ 3,524,338.00
Tracie Oliver — — — —

(1)Value is calculated as the price of our Common Stock upon exercise, less the exercise price, multiplied by the number of shares exercised.

(2)Value is calculated as the price of our Common Stock upon vesting, multiplied by the number of shares vested.

Termination Benefits — Potential Payments Upon Termination or Change in Control

The Company has the following severance or change of control arrangements with its ~~Named Executive Officers:~~

NEOs:

Dr. Anzalone’s employment agreement with the Company provides that, if the Company terminates Dr. Anzalone’s employment without Cause or if Dr. Anzalone terminates his employment for Good Reason, on his date of termination, Dr. Anzalone will receive aone-time lump sum payment equal to the sum of: (i) one month of base salary and (ii) premiums for 30thirty (30) days of medical and dental benefits. To receive such payments Dr. Anzalone is required to execute a general release in favor of the Company.

For purposes of Dr. Anzalone’s employment agreement:

“Cause” means (i) the conviction (by trial or upon a plea of nolo contendere) of a felony or other crime involving moral turpitude or the commission of any other material act or omission involving dishonesty, disloyalty or fraud with respect to the Company or any of its subsidiaries or any of their customers or suppliers, (ii) reporting to work under the influence of alcohol or illegal drugs, the use of illegal drugs (whether or not at the workplace) or other repeated conduct causing the Company or any of its subsidiaries substantial public disgrace or disrepute or economic harm, (iii) the engaging of gross misconduct and the failure to cease such conduct and rectify any harm to the Company resulting therefrom within 30 days after written demand therefor by the Company identifying with reasonable particularity such conduct and harm, or (iv) any other material breach by Dr. Anzalone of ~~the~~his employment agreement ~~by Executive~~ and the failure to cease such breach and rectify any harm to the Company within 30 days after written demand by the Company identifying with reasonable particularity such breach and harm; and

“Good Reason” means (i) ~~Executive’s~~Dr. Anzalone’s duties, responsibilities, titles or offices are diminished as compared to those described in ~~the~~his employment agreement without ~~Executive’s~~his written consent, and the Company fails to reinstate such duties, responsibilities, titles or offices within 30 days after written demand by ~~Executive~~Dr. Anzalone identifying with reasonable particularity the diminishment, (ii) the relocation of ~~Executive’s~~Dr. Anzalone’s base office to an office that is more than thirty (30) highway miles from Pasadena, CA, (iii) the failure of the Company to obtain a satisfactory agreement from any successor to assume and agree to perform the obligations under the


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employment agreement and (iv) any other material breach of ~~this~~Dr. Anzalone’s employment agreement by the Company and the failure to cease such breach and rectify any harm to ~~Executive~~Dr. Anzalone resulting within 30 days after written demand by ~~Executive~~Dr. Anzalone identifying with reasonable particularity the breach and harm.

Pursuant to his offer of employment by the Company, Mr. Myszkowski is entitled to severance pay equal to three months’ base salary plus an amount equal to the premiums on his medical and dental benefits for the same period upon termination of his employment without cause.


36

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Pursuant to his offer of employment by the Company, Mr. O’Brien is entitled to severance pay equal to six months’ base salary upon a qualifying termination of his employment without ~~cause~~case only upon change of control as defined in the Company’s 2013 Incentive Plan.

The Company has not entered into a severance arrangement with Dr. ~~Given.~~

San Martin, Dr. Hamilton, or Ms. Oliver.

Additionally, pursuant to the 2004 Equity Incentive Plan, the 2013 Incentive Plan, and the ~~2013~~2021 Incentive Plan, any unvested awards held by plan participants, including the ~~Named Executive Officers,~~NEOs, become fully vested upon a change of control of the Company, except as otherwise determined by the Board and except with respect to the outstanding awards held by the CEO whose awards will only become fully vested ~~upon~~if he experiences a qualifying termination of employment following a change of control.

The following tables set forth information regarding potential termination and change of control arrangements with our executive officers had their employment been terminated or a change in control of the Company taken place on September 30, ~~2019:~~

2022:


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2023 PROXY STATEMENT Executive Compensation

Termination Payments

Triggering Event    Salary
($)    Benefits
($)    Stock
Awards
(1)($)    Option
Awards
(1)($)    Total

           Termination by Employer without Cause

Christopher Anzalone (2)


56,875



1,888



—



—



58,673

Kenneth Myszkowski


107,500



8,619



—



—



116,119

Bruce D. Given


—



—



—



—



—

Patrick O’Brien


—



—



—



—



—

Zhen Li (3)


N/A



N/A



N/A



N/A



N/A

           Change in Control

Christopher Anzalone


—



—



—



—



—

Kenneth Myszkowski


107,500



8,619



3,980,425



73,448



4,169,992

Bruce D. Given


—



—



9,616,425



110,150



9,726,575

Patrick O’Brien


—



—



3,240,700



110,150



3,350,850

Zhen Li (3)


N/A



N/A



N/A



N/A



N/A

           Involuntary Termination Following a Change in Control

Christopher Anzalone


56,875



1,888



26,301,324



146,874



26,506,961

Patrick O’Brien


213,200



—



—



—



213,200

~~(1)~~	For stock awards the value is calculated as the number of unvested shares multiplied by the Company’s closing stock price at September 30, 2019 of $28.18. For option awards the value is calculated as the number of shares issuable upon unvested options multiplied by the difference between the Company’s closing stock price at September 30, 2019 of $28.18 less the applicable exercise price.


Triggering Event	Salary ($)	Benefits ($)	Stock Awards (1)($)	Option Awards (1)($)	Total
Termination by Employer without Cause
Christopher Anzalone (2)	72,529	2,026	—	—	74,555
Kenneth Myszkowski	125,982	8,825	—	—	134,807
Patrick O’Brien	—	—	—	—	—
James Hamilton	—	—	—	—	—
Tracie Oliver	—	—	—	—	—
Change in Control					—
Christopher Anzalone (2)	—	—	—	—	—
Kenneth Myszkowski	125,982	8,825	11,549,550	—	11,684,357
Patrick O’Brien	—	—	10,144,875	—	10,144,875
James Hamilton	—	—	7,881,788	—	7,881,788
Tracie Oliver	—	—	—	—	—
Involuntary Termination Following a Change in Control					—
Christopher Anzalone	72,529	2,026	106,131,000	—	106,205,555
Patrick O’Brien	249,312	—	—	—	249,312

(1)For stock awards the value is calculated as the number of unvested shares multiplied by the Company’s closing stock price at September 30, 2022 of $33.05.

(2)Dr. Anzalone’s employment contract also provides for payment of the values set forth above upon his resignation for “good reason” as defined in his employment agreement.

~~(2)~~	~~Dr. Anzalone’s employment contract also provides for payment of the values set forth above upon his resignation for “good reason” as defined in his employment agreement.~~
						51

~~(3)~~

~~Dr. Li’s employment with the Company terminated in February 2019.~~

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2023 PROXY STATEMENT Executive Compensation

CEO Pay Ratio

Pursuant to Item 402(u) of RegulationS-K, we are required to calculate and disclose the median of the annual total compensation of all of our employees (excluding our CEO, Dr. Anzalone), the annual total compensation of Dr. Anzalone, and the ratio of these two amounts.


					37

~~2020 PROXY STATEMENT~~ ~~Executive Compensation~~

Based on the fact that we had a significant number of new hires during fiscal 2022, we did not elect to use the same median employee as the prior year. Our median employee was identified using the entire population of our employees as of September 30, ~~2019~~2022 based on a consistently applied compensation measure, (“or CACM,~~”),~~ that reasonably reflects the annual compensation of our employees. The CACM selected by us for our disclosure included annual base salary, ~~overtime for theyear-to-date~~ ~~period ended September 30, 2019,~~ the cash bonus amount for fiscal ~~2019,~~2022, the grant-date fair value for stock-based awards (calculated in accordance with requirements for the Summary Compensation Table), and welfare and health benefits for fiscal ~~2019.~~

2022.

Based on the CACM methodology described above, we identified the median employee and calculated the ~~2019~~fiscal 2022 compensation for this selected employee in the same manner we determine the annual total compensation of our ~~Named Executive Officers~~NEOs for purposes of the Summary Compensation Table. The median ~~employee~~of the annual total compensation ~~is $179,403.~~of all our employees was $192,354.66. Dr. Anzalone’s ~~2019~~fiscal 2022 annual total compensation as disclosed in the Fiscal 2022 Summary Compensation Table ~~is $2,216,264.~~was $12,029,636. As a result, our CEO to median employee pay ratio for ~~2018~~fiscal 2022 is ~~12:~~60:1.

This pay ratio is a reasonable estimate calculated by a method consistent with the SEC requirements, described above, based on our payroll and employment records. As a result of a variety of factors, including employee populations, potential differences in the components used for the CACM, compensation philosophies and certain assumptions, pay ratios reported by other companies may not be comparable to our pay ratio. The pay ratio is not utilized by our management or our compensation committee for compensation-related decisions.


38						52

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Proposal Three — Approval of Amendment to Arrowhead Pharmaceuticals, Inc.’s Amended and Restated Certificate Of Incorporation To Increase The Number Of Authorized Shares Of Common Stock

Background Regarding Proposed Amendment

The Board is asking stockholders to approve an amendment to the Company’s Amended and Restated Certificate of Incorporation (the “Certificate”) to increase the authorized number of common shares, par value $0.001 per share (the “Common Stock”), from 145,000,000 to 290,000,000, which would also increase the total number of authorized shares of capital stock from 150,000,000 to 295,000,000 (the “Proposed Certificate Amendment”). If our stockholders approve the Proposed Certificate Amendment, which the Board has approved and declared advisable, we expect to file a certificate of amendment with the Delaware Secretary of State to increase the number of authorized shares of our common stock and capital stock as soon as practicable following stockholder approval. On filing of the certificate of amendment with the Delaware Secretary of State, the first sentence of Article FOURTH of the Certificate would be amended and restated in its entirety as follows:

“FOURTH: The total number of shares which the Corporation shall have authority to issue is 150,000,000295,000,000, of which 145,000,000290,000,000 shares shall be common stock, $.001 par value (“Common Stock”), and 5,000,000 shares shall be preferred stock, $.001 par value (“Preferred Stock”).”

Under the Proposed Certificate Amendment, the authorized number of shares of preferred stock, of which none are currently outstanding, would remain unchanged.

Purposes of the Proposed Amendment

As of January 19, 2023, the Record Date, our Common Stock share utilization was as follows:


	Number of Shares of Common Stock
Authorized for issuance		145,000,000
Issued and outstanding		106,706,695
Reserved for issuance
• Outstanding equity awards under our equity compensation plans and inducement awards		6,123,516
• Available for future grants under our equity compensation plans		7,053,236
• Available for future issuance under our existing at-the-market securities offering		7,807,620
Total share usage (issued and outstanding + reserved for issuance)		127,691,067
Total share usage as percentage of authorized		88.1%

As a result, only approximately 13,027,269,shares of our Common Stock (or 8.98% of the total authorized) remain available for future issuance.

The Board believes that the availability of additional authorized shares of Common Stock is needed to provide us with additional flexibility to issue Common Stock for a variety of general corporate purposes as the Board may determine to be desirable. This includes, but is not limited to, using Common Stock as consideration for acquisitions, mergers, business combinations or other corporate transactions, raising equity capital, including any future at-the-market equity programs, adopting additional employee benefit plans or reserving additional shares for issuance under existing plans, implementing stock splits or stock dividends and other general corporate purposes. The Company does not have any current intention to issue shares in connection with acquisitions or pursuant to any equity financing outside its existing equity compensation plans and at-the-market securities offering. However, unless our stockholders approve the Proposed Certificate Amendment, we may not have sufficient unissued and unreserved authorized shares to engage in similar transactions in the future. Further, our success also depends in part on our continued ability to attract, retain, and motivate highly qualified management and key personnel. If this proposal is not approved


						53

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2023 PROXY STATEMENT Executive Compensation

by our stockholders, the lack of unissued and unreserved authorized shares of Common Stock to provide future equity incentive opportunities could adversely impact our ability to achieve these goals.

Having additional authorized Common Stock available for future use will allow us to issue additional shares of Common Stock without the expense and delay of arranging a special meeting of stockholders. We may seek further increases in authorized shares from time to time in the future as considered appropriate by the Board.

Effect of Increasing the Number of Shares of Authorized Common Stock

The Proposed Certificate Amendment would not change the number of shares of Common Stock outstanding, nor will it have any immediate dilutive effect. However, if this proposal is approved, unless otherwise required by applicable law or Nasdaq rules, the Board will be able to issue the additional shares of Common Stock from time to time in its discretion without further action or authorization by the stockholders. Any future issuance of additional shares of Common Stock authorized by the Proposed Certificate Amendment may occur at times or under circumstances as to have a dilutive effect on earnings per share, book value per share or the percentage voting or ownership interest of the present holders of our Common Stock, none of whom have preemptive rights under the Certificate to subscribe for additional securities that we may issue.

The Proposed Certificate Amendment has been prompted by business and financial considerations. The Board currently is not aware of any attempt by a third-party to accumulate shares of Common Stock or take control of the Company by means of a merger, tender offer, or solicitation in opposition to management or the Board. Moreover, we currently have no plans to issue newly authorized shares of Common Stock to discourage third parties from attempting to take over the Company. However, the Proposed Certificate Amendment could, under certain circumstances, have an anti-takeover effect or delay or prevent a change in control of the Company by providing the Company the capability to engage in actions that would be dilutive to a potential acquiror, to pursue alternative transactions, or to otherwise increase the potential cost to acquire control of the Company. Thus, while we currently have no intent to use the additional authorized shares as an anti-takeover device, the Proposed Certificate Amendment may have the effect of discouraging future unsolicited takeover attempts.

Once the Proposed Certificate Amendment is approved, no further action by the stockholders would be necessary prior to the issuance of additional shares of Common Stock unless required by applicable law or Nasdaq rules. Each of the newly authorized shares of Common Stock will have the same rights and privileges as currently authorized shares of Common Stock. Adoption of the Proposed Certificate Amendment will not affect the rights of the holders of currently outstanding Common Stock, nor will it change the par value of the Common Stock.

A complete copy of the Company’s current Amended and Restated Certificate of Incorporation is available as an exhibit to our Annual Report on Form 10-K for the fiscal year ended September 30, 2022 (https://ir.arrowheadpharma.com/financial-information).

Effectiveness and Vote Required; Recommendation of the Board

The Proposed Certificate Amendment is binding. If the Proposed Certificate Amendment is approved, it will become effective upon filing of the certificate of amendment with the Secretary of State for the State of Delaware.

Proposal Three must be approved by the affirmative vote of a majority of the outstanding shares of Common Stock entitled to vote thereon. Abstentions and broker non-votes, if any, will have the same effect as a vote “AGAINST” this proposal.


			THE BOARD UNANIMOUSLY RECOMMENDS A VOTE “FOR” PROPOSAL THREE.


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Proposal Four — Ratification of Appointment of Independent Auditors

~~Proposal Four — Ratification of Appointment of Independent Auditors~~

Our Audit Committee, with the ratification of our Board, selected the accounting firm of Rose, Snyder & Jacobs, LLP (“RS&J”) as the Company’s independent auditors for the fiscal year ending September 30, ~~2020,~~2023, and that selection is now being submitted to the stockholders.

A representative of RS&J ~~will~~is expected to be available at the Annual Meeting to respond to appropriate stockholder questions or make any other statements such representative deems appropriate.

Stockholders are not required to ratify the appointment of RS&J as our independent auditor. However, we are submitting the appointment for ratification as a matter of good corporate practice. If stockholders fail to ratify the appointment, the Audit Committee will consider whether or not to retain RS&J. Even if the appointment is ratified, the Audit Committee may direct the appointment of a different independent auditor at any time during the year if it determines that such a change would be in the best interests of the Company and our stockholders.

Vote Required; Recommendation of the Board

In order to be ratified, Proposal Four must be approved by ~~a majority of~~the Required Vote, assuming a quorum is present. For this purpose, abstentions and broker non-votes, if any, will be counted as a vote ~~against~~“AGAINST” the proposal.

THE BOARD UNANIMOUSLY RECOMMENDS A VOTE

“FOR” PROPOSAL FOUR.

~~2020~~Table of Contents

2022 PROXY STATEMENT Audit Fees

Audit Fees

The Audit Committee regularly reviews and determines whether specific projects or expenditures with our independent auditors, RS&J, may potentially affect their independence. The Audit Committee’s policy is topre-approve all audit and permissiblenon-audit services provided by RS&J.Pre-approval is generally provided by the Audit Committee for up to one year, detailed to the particular service or category of services to be rendered and is generally subject to a specific budget. The Audit Committee may alsopre-approve additional services of specific engagements on acase-by-case basis. All engagements of our independent registered public accounting firm in ~~2019~~2022 and ~~2018~~2021 werepre-approved by the audit committee.

The following table sets forth the aggregate audit fees ~~invoiced~~billed and expected to be billed by RS&J for the indicated fiscal ~~years ended September 30, 2019~~year and ~~September 30, 2018:~~

      Year Ended September 30,
              2019                     2018

Audit fees (1)
   $ 231,325    $ 194,000

Audit-related fees (2)
   17,000    59,500

Tax Fees
   —    —

All other fees
   —    —

Total
   $ 248,325    $ 253,500

the fees billed by RS&J for all other services rendered during the indicated fiscal year:


	Year Ended September 30,
	2022	2021
Audit fees (1)	$324,750	$295,400
Audit-related fees (2)	45,200	70,250
Tax Fees	—	—
All other fees	—	—
Total	$369,950	$365,650

(1)Fees invoiced by RS&J include year-end audit and periodic reviews of Forms 10-Q and 10-K.

(2)Fees invoiced by RS&J related to Comfort Letters and Consents for financings and registration statements, and other agreed-upon procedures.

~~(1)~~

~~Fees invoiced by RS&J includeyear-end~~ ~~audit and periodic reviews of Forms10-Q~~ ~~and10-K.~~

~~(2)~~

~~Fees invoiced by RS&J related to Comfort Letters and Consents for financings and registration statements, and other agreed-upon procedures.~~


40										56

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2022 PROXY STATEMENT Report of the Audit Committee

Report of the Audit Committee

The following is the report of the Audit Committee with respect to the Company’s audited financial statements for fiscal ~~2019,~~2022, which include the consolidated balance sheets of the Company as of September 30, ~~2019~~2022 and September 30, ~~2018,~~2021, and the related consolidated statements of operations, stockholders’ equity and cash flows for the fiscal years ended September 30, ~~2019,~~2022, September 30, ~~2018~~2021 and September 30, ~~2017,~~2020, and the notes thereto.

Composition. At September 30, ~~2019, The~~2022, the Audit Committee of the Board was comprised of ~~three~~four directors and ~~operates~~operated under a written charter adopted by the Board. The members of the Audit Committee for fiscal 2022 were William Waddill, ~~Mauro Ferrari~~Marianne De Backer, Adeoye Olukotun, and Michael S. Perry. All members of the Audit Committee were “independent,” as defined in Rule10A-3 under the Exchange Act and Rule 5605(c) of the Nasdaq Marketplace Rules, and are financially literate.

Responsibilities. The responsibilities of the Audit Committee include engaging an accounting firm as the Company’s independent registered public accounting firm. Management has primary responsibility for the Company’s internal controls and financial reporting process. The independent registered public accounting firm is responsible for performing an independent audit of the Company’s consolidated financial statements in accordance with generally accepted auditing standards and for issuing a report thereon. The Audit Committee’s responsibility is to oversee these processes.

Review with Management and independent registered public accounting ~~firm.~~ ~~On November 18, 2019, the Audit Committee consisted of William Waddill, Mauro Ferrari and Michael S. Perry. On that date, the~~firm. The Audit Committee met separately to review the Company’s consolidated audited financial statements and held discussions with management and RS&J. Management represented to the Audit Committee that the Company’s consolidated financial statements were prepared in accordance with generally accepted accounting principles. The members of the Audit Committee discussed with RS&J matters required to be discussed under the applicable standards of the Public Company Accounting Oversight ~~Board.~~Board (“PCAOB”) and the SEC. The Company’s independent registered public accounting firm also provided to the Audit Committee the written disclosures and the letter required by the ~~Public Company Accounting Oversight Board~~PCAOB regarding the independent registered public accounting firm’s communications with the Audit Committee concerning independence and the Audit Committee discussed the firm’s independence with RS&J.

Conclusion. Based upon the Audit Committee’s review of the financial statements and discussions with management and RS&J, the Audit Committee’s review of the representations of management and the report of RS&J to the Audit Committee, the Audit Committee recommended that the Board include the audited consolidated financial statements in the Company’s Annual Report on Form10-K for the fiscal year ended September 30, ~~2019,~~2022, as filed with the SEC.

This report is submitted by the Audit Committee of the Board.

William Waddill, ~~Chairman~~

~~Mauro Ferrari~~

Committee Chair

Marianne De Backer

Adeoye Olukotun

Michael S. Perry

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2022 PROXY STATEMENT Voting Securities of Principal Stockholders and Management

Voting Securities of Principal Stockholders and Management

The following table sets forth the beneficial ownership of the Company’s Common Stock as of January ~~14, 2020,~~10, 2023, by (i) each of the ~~named executive officers~~NEOs named in the table under “Executive Compensation and Related Information,” (ii) each director, (iii) all current directors and executive officers as a group, and (iv) the holders of greater than 5% of our total shares outstanding known to us. Unless otherwise specified in the footnotes to the table below, the persons and entities named in the table have sole voting and investment power with respect to all shares beneficially owned, subject to community property laws, where applicable, and the address of each stockholder is c/o Arrowhead Pharmaceuticals, Inc., 177 E. Colorado Blvd, Suite 700, Pasadena, CA, 91105 unless otherwise indicated.

Number and Percentage of Shares
Beneficially Owned (1)



      Shares



      Percentage

5% Beneficial Owners



BlackRock Inc (2)
55 East 52nd Street, New York, NY 10055



14,869,280



14.6

%

The Vanguard Group (3)
100 Vanguard Blvd., Malvern, PA 19355



10,844,571



10.7

%

Executive Officers and Directors



Christopher Anzalone (4)



2,350,780



2.3

%

Kenneth Myszkowski (5)



354,402



*

Bruce D. Given (6)



713,993



*

Patrick O’Brien (7)



255,875



*

Douglass Given



172,925



*

Michael S. Perry (8)



113,000



*

Mauro Ferrari (9)



26,900



*

William Waddill



46,500



*

Marianne De Backer



—



*

All Executive Officers and Directors as a group (9 persons) (10)



4,034,375



4.0

%


	Number and Percentage of Shares Beneficially Owned (1)
	Shares	Percentage
5% Beneficial Owners
BlackRock Inc (2) 55 East 52nd Street, New York, NY 10055	12,008,063	11.3%
The Vanguard Group (3) 100 Vanguard Blvd., Malvern, PA 19355	9,358,719	9.5%
Named Executive Officers and Directors
Christopher Anzalone (4)	3,720,714	3.5%
Kenneth Myszkowski	396,704	*
Patrick O’Brien	413,375	*
Javier San Martin	151,500	*
James Hamilton	191,484	*
Tracie Oliver	70,500	*
Douglass Given	124,135	*
Michael S. Perry	99,767	*
Mauro Ferrari	50,838	*
William Waddill	36,817	*
Marianne De Backer	31,267	*
Adeoye Olukotun	19,217	*
Victoria Vakiener	23,284	*
All Executive Officers and Directors as a group (11 persons)	5,329,602	5.0%

*Less than 1%

(1)Based on 106,624,931 shares of Common Stock issued and outstanding as of January 10, 2023. Shares not outstanding but deemed beneficially owned by virtue of the right of a person to acquire them as of January 10, 2023, or within sixty days of such date are treated as outstanding only when determining the percentage owned by such individual and when determining the percentage owned by a group.

(2)Based on Amendment No. 5 to Schedule 13G/A filed January 27, 2022 by BlackRock Inc.. According to Amendment No. 5, BlackRock Inc. has sole voting power and sole dispositive power over 11,860,689 shares and 12,008,063 shares, respectively, and has shared voting power and shared dispositive power over 0 shares and 0 shares, respectively.

(3)Based on Amendment No. 3 to Schedule 13G/A filed February 09, 2022. According to Amendment No. 3, The Vanguard Group has sole voting power and sole dispositive power over 0 and 9,358,719 shares, respectively, and has shared voting power and shared dispositive power over 191,955 shares and 281,424 shares, respectively.

(4)Includes 0 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 10, 2023.

*	~~Less than 1%~~

~~(1)~~

Based on 101,529,466 shares of Common Stock issued and outstanding as of January 14, 2020. Shares not outstanding but deemed beneficially owned by virtue of the right of a person to acquire them as of January 14, 2020, or within sixty days of such date are treated as outstanding only when determining the percentage owned by such individual and when determining the percentage owned by a group.

~~(2)~~

Based on a Schedule 13G filed October 10, 2019 by The Vanguard Group. According to the Form 13G, The Vanguard Group has sole voting power and sole dispositive power over 198,567 shares and 10,639,170 shares, respectively, and has shared voting power and shared dispositive power over 16,160 shares and 205,041 shares, respectively.

~~(3)~~

Based on Amendment No. 1 to Schedule 13G filed on June 7, 2019 by BlackRock Inc. According to the Amendment No. 1, BlackRock Inc. has sole voting power of 14,646,012 shares and sole dispositive power with respect to all of the Arrowhead shares it beneficially holds.

~~(4)~~

~~Includes 945,543 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~

~~(5)~~

~~Includes 149,467 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~

~~(6)~~

~~Includes 350,000 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~

~~(7)~~

~~Includes 150,000 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~

~~(8)~~

~~Includes 77,000 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~

~~(9)~~

~~Includes 20,000 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~

~~(10)~~

~~Includes 1,692,010 shares issuable upon the exercise of stock options that are exercisable within 60 days of January 14, 2020.~~


42										58

~~2020~~Table of Contents

2022 PROXY STATEMENT Equity Compensation Plan Information

Equity Compensation Plan Information

The following table provides information as of September 30, ~~2019~~2022 with respect to shares of our Common Stock that may be issued under our equity compensation plans.

Equity Compensation Plan Information



Number of
Shares to
be Issued
upon
exercise of
outstanding
options,
warrants
and rights



Weighted
average
exercise price
of outstanding
options,
warrants and
rights



Number of
securities
remaining
available for
future issuance
under equity
compensation
plans (excluding
securities
reflected in
column (a))

Equity compensation plans approved by security holders (1)



5,984,992



$

7.00



341,294

Equity compensation plans not approved by security holders (2)



851,511



$

13.57



—

Total



6,836,503



$

8.16



341,294

~~(1)~~

Includes options outstanding representing 1,099,337 and 2,831,322 shares of Common Stock under the 2004 Equity Incentive Plan and the 2013 Incentive Plan, respectively. Also includes 2,054,333 restricted stock units subject to the 2013 Incentive Plan.

~~(2)~~

~~Includes 843,011 inducement option grants and 8,500 inducement restricted stock unit grants issued to newly hired employees.~~


	Equity Compensation Plan Information
	Number of Shares to be Issued upon exercise of outstanding options, warrants and rights	Weighted average exercise price of outstanding options, warrants and rights	Number of securities remaining available for future issuance under equity compensation plans (excluding securities reflected in column (a))
Equity compensation plans approved by security holders (1)	6,790,815	$46.04	7,190,077
Equity compensation plans not approved by security holders (2)	1,617,050	$43.88	—
Total	8,407,865	$45.62	7,190,077

(1)Includes options outstanding representing 175,083, 2,543,301 and 3,000 shares of Common Stock under the 2004 Equity Incentive Plan, the 2013 Incentive Plan, and the 2021 Incentive Plan, respectively. Also includes 3,145,886 and 923,545 restricted stock units subject to the 2013 Incentive Plan and the 2021 Incentive Plan, respectively. There is no exercise price associated with a restricted stock unit award. Accordingly, these have been excluded from the column in the table reporting the weighted-average exercise price of outstanding awards.

(2)Includes 778,425 inducement option grants and 838,625 inducement restricted stock unit grants issued to newly hired employees.

Current Executive Officers of the Registrant

The names, ages, and positions of our current executive officers serving as of January ~~14, 2020~~10, 2023 are provided below. Biographical information regarding these officers is set forth under the following table, except for Dr. Anzalone, whose biography is set forth above with our other directors.

Name

Age

~~Name~~

~~Age~~

Position with Arrowhead

Christopher Anzalone

Chief Executive Officer & President and Director

Kenneth A. Myszkowski

Chief Financial Officer

~~Bruce Given~~

Javier San Martin

Chief Medical Officer

James Hamilton

Chief of Discovery and Translational Medicine

Patrick O’Brien

Chief Operating Officer

and General Counsel

~~Patrick O’Brien~~

Tracie Oliver

~~General Counsel~~

Chief Commercial Officer

Kenneth A. Myszkowski, Chief Financial Officer, joined the Company in 2009. Prior to joining Arrowhead, Mr. Myszkowski served as the corporate controller for Broadwind Energy, a public energy company which provides products and services to the wind energy industry. Previous to his position at Broadwind, Mr. Myszkowski was controller for Epcor USA, the U.S. headquarters for Epcor Utilities, Inc., a public energy company. Prior to Epcor, Mr. Myszkowski was controller for twostart-up ventures: NanoInk, specializing in Dip Pen Nanolithography, a nanofabrication technology, and Delphion, which providedon-line tools for intellectual property research. Mr. Myszkowski also held several corporate roles at FMC Corporation and Premark International, both Fortune 500 conglomerates. He began his career in the audit practice of Arthur Andersen & Co. in Chicago, Illinois. Mr. Myszkowski received his undergraduate degree from the University of Illinois, and his MBA from the University of Chicago Booth School of Business. He is a certified public accountant.

Patrick C. O’Brien, Chief Operating Officer and General Counsel, joined the Company in December 2014, where he has served as Chief Operating Officer since July 2022 and as General Counsel since 2014. Mr. O’Brien has practiced

~~2020~~Table of Contents

2023 PROXY STATEMENT Equity Compensation Plan Information

~~Dr.~~ ~~Bruce Given~~, Chief Operating Officer, joined the Company in 2011. Dr. Given was a member of the board of directors for ICON, plc. from 2004 until his retirement in 2013 and Chairman of its Board of Directors from 2010 to 2013. Dr. Given served as the President and Chief Executive Officer, and as a member of the board of directors of Encysive Pharmaceuticals, an~~R&D-based~~ commercial pharmaceutical company, roles he held from 2002 through 2007. Subsequent to his tenure at Encysive until 2011, Dr. Given was President of Bruce Given Consulting, a firm that provides consulting services to biotech companies. Since October 1, 2009, Dr. Given has been a director of Calando Pharmaceuticals, Inc., and from February 2010 until its dissolution in October 2014, Dr. Given was the Chief Executive Officer of Leonardo Biosystems, Inc., in which Arrowhead held a minority equity interest. Prior to his tenure at Encysive, Dr. Given held several senior executive roles at Johnson & Johnson, Sandoz Pharmaceuticals and Schering-Plough. Dr. Given obtained his bachelor of sciences degree from Colorado State University, graduating Phi Beta Kappa. He received his M.D. degree with honors from the University of Chicago, Pritzker School of Medicine and completed his medical training at the University of Chicago and at Brigham and Women’s Hospital in Boston, where he was a Clinical Fellow at Harvard Medical School. He is board certified in internal medicine and endocrinology and metabolism and has authored 33 scientific publications. Dr. Bruce Given is a brother of Dr. Douglass Given, a director of the company.

~~Patrick C. O’Brien~~~~, General Counsel, joined the Company in December 2014. Mr. O’Brien has practiced~~

in the healthcare legal field for over 2530 years. Before joining the Company, from 2012 to 2014, Mr. O’Brien was with Shire, as global pharmaceutical company, where he was Group Vice President, Law. Immediately prior to working with Shire he was a partner with the international law firm of Holland & Knight LLP in its Washington, DC office. In 2010, Mr. O’Brienco-founded the law firm O’Brien Gould PLLC which joined Holland & Knight in 2011. From 2009 to 2010, Mr. O’Brien was a partner in Burke O’Neil LLC. From 2001 to 2009, Mr. O’Brien served in several legal roles with Johnson & Johnson, including serving as Vice President of Law for J&J’s Centocor Ortho-Biotech unit. Mr. O’Brien previously served as Regulatory Counsel with the United States Food & Drug Administration. Mr. O’Brien was awarded a BS in Pharmacy and a PharmD from the University of Arizona before completing a residency in Clinical Pharmacy with the University of Illinois at Chicago Hospital. He was also awarded his JD from the University of Arizona.

~~Dr.~~ ~~Curt Bradshaw,~~Chief Scientific Officer, joined the Company in November 2019. From 2018 to November 2019 Dr. Bradshaw was President, Chief Scientific Officer, and a member of the board of directors for Tollnine, a company he

~~co-founded~~ to develop novel antibody conjugates for immuno-oncology. From 2012 — 2019 he served as Chief Scientific Officer and a member of the board of directors of Solstice Biologics, where he managed and oversaw all company operations and research exploring novel siRNA technologies for the development of human therapeutics. Before Solstice, Dr. Bradshaw was Vice President of Research and Development and Chief Scientific Officer at Traversa Therapeutics. At Traversa, he had primary R&D oversight and was a key strategic contributor to internal technology development, business strategy, and oversaw research alliances with multiple major pharmaceutical collaborators. Prior to Traversa, Dr. Bradshaw spent 7 years at CovX Research, a cornerstone of the Pfizer, Inc. Bioinnovation and Biotherapeutics Center. Prior to CovX, he spent 4 years at Ligand Pharmaceuticals and was responsible for the chemical development of clinical-phase active pharmaceutical ingredients. Dr. Bradshaw started his career at Abbott Laboratories, where he spent 6 years as a Research Chemist, Senior Research Chemist, and Project Leader. He received a PhD. in Organic Chemistry from Texas A&M University.

Javier San Martin, Chief Medical Officer, joined the Company in November 2019. Dr. San Martin previously served as Senior Vice President and Head of Global Clinical Development at Ultragenyx from 2013 until November 2019. At Ultragenyx he led the development of burosumab, a novel drug for the treatment ofX-Linked Hypophosphatemia approved across major regions including the United States, the European Union, and Canada. Before his tenure at Ultragenyx, he served as Senior Vice President of Clinical Development at Alder Biopharmaceuticals, where he was responsible for managing the medical, regulatory, and clinical operations group focused on early clinical programs. From 2006 to 2011, Dr. San Martin was a Global Development Leader at Amgen, Inc., where he was responsible for two major development programs. He directed the romosozumab clinical program through the end of phase II, and before that, was responsible for the development and approval of denosumab, the largest branded anti-osteoporosis treatment for postmenopausal osteoporosis and the first monoclonal antibody to address a very prevalent disease treated by primary care physicians. Prior to his time at Amgen, he spent seven years at Eli Lilly and Company, supporting late stage clinical development as well as medical affairs activities, including the successful launch of Evista and Forteo. He received his medical degree from the University of Buenos Aires Medical School and completed his residence in internal medicine at CEMIC University Hospital in Buenos Aires, Argentina, serving as Chief Resident, and, thereafter, as Attending Physician responsible for the internal medicine ward.

James ~~Hassard,~~Hamilton, Chief of Discovery & Translational Medicine, joined the Company in 2014. He is responsible for target discovery as well as non-clinical and early clinical development. Previously, Dr. Hamilton served as Vice President, Clinical Development, responsible for clinical strategy, clinical trial design and execution including early translational and mid-stage development of all Arrowhead programs. He is experienced in multiple disease areas including virology, hepatology, cardiovascular disease, rare disease and oncology. Dr. Hamilton led the clinical development of ARO-HBV (now JNJ-3989), which was licensed to Janssen Pharmaceuticals. In parallel, Dr. Hamilton served as Head of Corporate Development and led Arrowhead’s in-licensing transaction of Novartis’s RNAi assets, as well as the out-licensing of ARO-LPA (now AMG890) to Amgen and the ARO-AAT partnership with Takeda. Dr. Hamilton started his employment at Arrowhead as Medical Director and Head of Corporate development. He holds both MD and MBA degrees from The Ohio State University. He is a licensed physician and completed residency training with board certification in emergency medicine.

Tracie Oliver, Chief Commercial Officer, joined Arrowhead in June 2022. Ms. Oliver has over 30 years of global experience in the ~~Company~~biopharmaceutical industry leading both R&D and Commercial organizations. Prior to joining Arrowhead, she had her own consulting practice focused on development of commercial and development strategy for small biotech companies since 2019. She joined Shire Pharmaceuticals in ~~January 2020. Mr. Hassard served as Senior Vice President~~2016 through the acquisition of ~~Marketing~~Baxalta and ~~Market Access at Coherus BioSciences since 2016, where he~~ was ~~instrumental in building the commercial organization~~Global Head of New Product Planning and ~~commercial capabilities. Heco-led~~ ~~the launch of Coherus’ first product, a biosimilar, pegfilgrastim; one of the most successful pharmaceutical launches of~~Device Strategy until 2019. Prior to ~~his tenure~~that she held several commercial roles at ~~Coherus, Mr. Hassard~~Baxter and Baxalta including establishing a new oncology franchise and leading the North America Immunology Business Unit and Autoimmune Franchise. Ms. Oliver began her career in the biopharmaceutical industry with Johnson & Johnson and served as ~~Vice President~~head of ~~Marketing at Medivation, prior to~~Ortho Biotech Nephrology Business Unit in Canada, Ortho McNeil Neurologics, and ~~through its acquisition by Pfizer Pharmaceuticals. From 1999 to~~

McNeil Pediatrics in the USA and led an internal venture developing an allogeneic cell therapy for acute ischemic stroke. She received her BSc and MSc from Queen’s University in Kingston, Ontario and her MBA from the Shulich School of Business, York University, Toronto.


44

~~2020 PROXY STATEMENT~~ ~~Equity Compensation Plan Information~~

2016, he held multiple increasingly senior commercial roles at Amgen, Inc., across sales and marketing, domestic and international, including an assignment as General Manager of Amgen Portugal. He was responsible for the launch, growth, and subsequent life-cycle management of several oncology and nephrology products, including darbepoetin alfa and cinacalcet. Prior to Amgen, Mr. Hassard spent several years at Schering-Plough Canada, in sales and marketing roles, in the therapeutic areas of oncology, cardiovascular and hepatitis. He received his Bachelor of Science in pharmacology from the University of Toronto and a master’s in business administration from Nova Southeastern University, Florida.

~~2020~~Table of Contents

2022 PROXY STATEMENT Review and Approval of Related-Party Transactions

Review and Approval of Related-Party Transactions

Our Board has adopted written policies and procedures for the review and approval of related-party transactions and has delegated to the Audit Committee the authority to review and approve the material terms of any proposed related-party transactions. To the extent that a proposed related-party transaction may involve anon-employee director or nominee for election as a director and may be material to a consideration of that person’s independence, the matter may also be considered by the other disinterested directors.

Pursuant to our Code of Business Conduct and Ethics and our Corporate Governance Committee Charter, each of our officers, directors and employees must disclose related-party transactions to our Board. In order to avoid conflicts of interest, our executive officers and directors may not acquire any ownership interest in any supplier, customer or competitor (other than nominal amounts of stock in publicly traded companies), enter into any consulting or employment relationship with any customer, supplier or competitor, or engage in any outside business activity that is competitive with any of our businesses, without first disclosing the proposed transaction. After the proposed transaction has been disclosed, a determination will be made by our Board or Audit Committee as to what course to follow, depending on the nature or extent of the conflict. Furthermore, our executive officers and directors may not serve on any board of directors of any customer, supplier or competitor unless such board service has been disclosed to us and approved by our Board.

In determining whether to approve or ratify a related-party transaction, the Board and/or Audit Committee may consider, among other factors it deems appropriate, the potential benefits to ~~us,~~the Company, the impact on a director’s or nominee’s independence or an executive officer’s relationship with or service to ~~us,~~the Company, whether the related-party transaction is on terms no less favorable than terms generally available to an unaffiliated third party under the same or similar circumstances, and the extent of the related party’s interest in the transaction. In deciding to approve a transaction, the Board or Audit Committee may, in its sole discretion, impose such conditions as it deems appropriate on us or the related party in connection with its approval of any transaction. Any transactions involving the compensation of executive officers, however, are reviewed and approved by the Compensation Committee. If a related-party transaction will be ongoing, the Audit Committee may establish guidelines to be followed in our ongoing dealings with the related party. Thereafter, the Audit Committee reviews and assesses the ongoing relationship with each related party to see that it is in compliance with the Audit Committee’s guidelines and that the related-party transaction remains appropriate.


46										61

~~2020~~Table of Contents

2022 PROXY STATEMENT Certain Relationships and Related Transactions, and Director Independence

Certain Relationships and Related Transactions, and Director Independence

As of September 30, ~~2019,~~2022, a majority of the members of the Board are independent directors, as defined by the Nasdaq Marketplace Rules. The Board has determined that all of the Company’s directors are independent, except Dr. Anzalone, the Company’s Chief Executive Officer, and Dr. Douglass Given, the brother of the Company’s former Chief Operating Officer.Non-employee directors do not receive consulting, legal or other fees from the Company, other than Board compensation.

Vincent Anzalone is the Company’s Vice President, Investor Relations and the brother of Christopher Anzalone, the Company’s ~~CEO.~~Chief Executive Officer. Vincent Anzalone earned base salary and bonus of ~~$273,560~~$311,173 during fiscal year ~~2019.~~2022. His current base salary is ~~$244,860.~~$294,581. In January ~~2019,~~2022, Mr. Anzalone was awarded ~~40,000~~15,000 restricted stock units, and this award vests in four annual tranches from the grant date. The grant date fair value of this award is ~~$496,800.~~

$994,500.

Annual Report on Form10-K

The Company will mail, without charge to any stockholder upon written request, a copy of the Company’s Annual Report on Form10-K for the year ended September 30, ~~2019~~2022 including the financial statements, schedules and a list of exhibits. Requests should be sent to Arrowhead Pharmaceuticals, Inc., 177 E. Colorado Blvd., Suite 700, Pasadena, CA 91105, Attn: Corporate Secretary, Phone(626) 304-3400.

Stockholders Sharing the Same Address

We may satisfy SEC rules regarding delivery of proxy statements including the proxy statement, annual report and Notice, by delivering a single Notice and, if applicable, a single set of proxy materials to an address shared by two or more of our stockholders. This delivery method can result in meaningful cost savings for us. To take advantage of this opportunity, we may deliver only one Notice, and if applicable, a single set of proxy materials to multiple stockholders who share an address, unless contrary instructions are received prior to the mailing date. Similarly, if you share an address with another stockholder and have received multiple copies of our Notice and/or other proxy materials, you may write or call us at the address and phone number below to request delivery of a single copy of these materials in the future. We undertake to deliver promptly upon written or oral request a separate copy of the Notice and/or other proxy materials to a stockholder at a shared address to which a single copy of these documents was delivered. If you hold stock as a record stockholder and prefer to receive separate copies of a Notice, and if applicable, other proxy materials either now or in the future, please contact us at the address provided below. If your stock is held through a brokerage firm or bank and you prefer to receive separate copies of a Notice and, if applicable, other proxy materials either now or in the future, please contact your brokerage firm or bank.

Arrowhead Pharmaceuticals, Inc.

177 E. Colorado Blvd., Suite 700

Pasadena CA 91105

Attn: Corporate Secretary

Phone(626) 304-3400


						62

Table of Contents

2022 PROXY STATEMENT Certain Relationships and Related Transactions, and Director Independence

Other Matters

The Company knows of no other matters to be submitted at the Annual Meeting. If any other matters properly come before the meeting, it is the intention of the persons named in the proxy card to vote ~~the shares they represent as the Board may recommend.~~

on such matters in accordance with their best judgment.


BY ORDER OF THE BOARD OF DIRECTORS

/s/ Patrick O’Brien
Patrick O’Brien,
Secretary
Pasadena, California
January ~~28, 2020~~30, 2023

~~2020~~Table of Contents

PRELIMINARY PROXY ~~STATEMENT~~ SUBJECT TO COMPLETION

~~Exhibit A~~

~~Exhibit A~~

~~Amended and Restated~~

~~Bylaws of~~

~~Arrowhead Pharmaceuticals, Inc.~~

~~ARTICLE I~~

~~STOCKHOLDERS~~

~~Section 1.1Annual Meeting~~.

~~(a)General. The annual meeting~~Table of ~~stockholders shall be held at the hour, date and place within or without the State~~Contents

Table of Delaware which is fixed by the Board of Directors, which time, date and place may subsequently be changed at any time by vote of the Board of Directors. If no annual meeting has been held for a period of thirteen (13) months after the corporation’s last annual meeting, a special meeting in lieu thereof may be held, and such special meeting shall have, for the purposes of these bylaws or otherwise, all the force and effect of an annual meeting. Any and all references hereafter in these bylaws to an annual meeting or annual meetings also shall be deemed to refer to any special meeting(s) in lieu thereof.

~~(b)Notice of Stockholder Business and Nominations~~.

(1) Nominations of persons for election to the Board of Directors and the proposal of other business to be considered by the stockholders may be brought before an annual meeting: (i) by or at the direction of the Board of Directors, or (ii) by any stockholder of the corporation who was a stockholder of record at the time of giving of notice provided for in this bylaw, who is entitled to vote at the meeting, who is present (in person or by proxy) at the meeting and who complies with the notice procedures set forth in this bylaw as to such nomination or business. For the avoidance of doubt, the foregoing clause (ii) shall be the exclusive means for a stockholder to bring nominations or business properly before an annual meeting (other than matters properly brought under RuleContents

~~14a-8~~
~~(or any successor rule) under the Securities Exchange Act of 1934, as amended (the “Exchange Act~~”)), and such stockholder must comply with the notice and other procedures set forth in Article I, Section 1.1(b)(2) and (3) of this bylaw to bring such nominations or business properly before an annual meeting. In addition to the other requirements set forth in this bylaw, for any proposal of business to be considered at an annual meeting, it must be a proper subject for action by stockholders of the corporation under Delaware law.

(2) For nominations or other business to be properly brought before an annual meeting by a stockholder pursuant to clause (ii) of Article I, Section 1.1(b)(1) of this bylaw, the stockholder must (i) have given Timely Notice (as defined below) thereof in writing to the Secretary of the corporation, (ii) have provided any updates or supplements to such notice at the times and in the forms required by this bylaw and (iii) together with the beneficial owner(s), if any, on whose behalf the nomination or business proposal is made, have acted in accordance with the representations set forth in the Solicitation Statement (as defined below) required by this bylaw. To be timely, a stockholder’s written notice shall be received by the Secretary at the principal executive offices of the corporation not later than the close of business on the 90^th ~~day nor earlier than the close of business on the 120~~^th ~~day prior to theone-year~~ anniversary of the preceding year’s annual meeting; provided, however, that in the event the annual meeting is first convened more than 30 days before or more than 60 days after such anniversary date, or if no annual meeting were held in the preceding year, notice by the stockholder to be timely must be received by the Secretary of the corporation not later than the close of business on the later of the 90^th ~~day prior to the scheduled date of such annual meeting or the 10~~^th ~~day following the day on which public announcement of the date of such meeting is first made (such notice within such time periods shall be referred to as “Timely Notice”). Such stockholder’s Timely Notice shall set forth:~~

(A) as to each person whom the stockholder proposes to nominate for election or reelection as a director, all information relating to such person that is required to be disclosed in solicitations of proxies for election of directors in an election contest, or is otherwise required, in each case pursuant to Regulation 14A under the Exchange Act (including such person’s written consent to being named in the proxy statement as a nominee and to serving as a director if elected);

(B) as to any other business that the stockholder proposes to bring before the meeting, a brief description of the business desired to be brought before the meeting, the reasons for conducting such business at the meeting, and any material interest in such business of each Proposing Person (as defined below);

(C) (i) the name and address of the stockholder giving the notice, as they appear on the corporation’s books, and the names and addresses of the other Proposing Persons (if any) and (ii) as to each Proposing Person, the following


					~~A-1~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

information: (a) the class or series and number of all shares of capital stock of the corporation which are, directly or indirectly, owned beneficially or of record by such Proposing Person or any of its affiliates or associates (as such terms are defined in Rule~~12b-2~~ promulgated under the Exchange Act), including any shares of any class or series of capital stock of the corporation as to which such Proposing Person or any of its affiliates or associates has a right to acquire beneficial ownership at any time in the future, (b) all Synthetic Equity Interests (as defined below) in which such Proposing Person or any of its affiliates or associates, directly or indirectly, holds an interest including a description of the material terms of each such Synthetic Equity Interest, including without limitation, identification of the counterparty to each such Synthetic Equity Interest and disclosure, for each such Synthetic Equity Interest, as to (x) whether or not such Synthetic Equity Interest conveys any voting rights, directly or indirectly, in such shares to such Proposing Person, (y) whether or not such Synthetic Equity Interest is required to be, or is capable of being, settled through delivery of such shares and (z) whether or not such Proposing Person and/or, to the extent known, the counterparty to such Synthetic Equity Interest has entered into other transactions that hedge or mitigate the economic effect of such Synthetic Equity Interest, (c) any proxy (other than a revocable proxy given in response to a public proxy solicitation made pursuant to, and in accordance with, the Exchange Act), agreement, arrangement, understanding or relationship pursuant to which such Proposing Person has or shares a right to, directly or indirectly, vote any shares of any class or series of capital stock of the corporation, (d) any rights to dividends or other distributions on the shares of any class or series of capital stock of the corporation, directly or indirectly, owned beneficially by such Proposing Person that are separated or separable from the underlying shares of the corporation, and (e) any performance-related fees (other than an asset based fee) that such Proposing Person, directly or indirectly, is entitled to based on any increase or decrease in the value of shares of any class or series of capital stock of the corporation or any Synthetic Equity Interests (the disclosures to be made pursuant to the foregoing clauses (a) through (e) are referred to, collectively, as “~~Material Ownership Interests~~”) and (iii) a description of the material terms of all agreements, arrangements or understandings (whether or not in writing) entered into by any Proposing Person or any of its affiliates or associates with any other person for the purpose of acquiring, holding, disposing or voting of any shares of any class or series of capital stock of the corporation;

(D) (i) a description of all agreements, arrangements or understandings by and among any of the Proposing Persons, or by and among any Proposing Persons and any other person (including with any proposed nominee(s)), pertaining to the nomination(s) or other business proposed to be brought before the meeting of stockholders (which description shall identify the name of each other person who is party to such an agreement, arrangement or understanding), and (ii) identification of the names and addresses of other stockholders (including beneficial owners) known by any of the Proposing Persons to support such nominations or other business proposal(s), and to the extent known the class and number of all shares of the corporation’s capital stock owned beneficially or of record by such other stockholder(s) or other beneficial owner(s); and

(E) a statement whether or not the stockholder giving the notice and/or the other Proposing Person(s), if any, will deliver a proxy statement and form of proxy to holders of, in the case of a business proposal, at least the percentage of voting power of all of the shares of capital stock of the corporation required under applicable law to approve the proposal or, in the case of a nomination or nominations, at least the percentage of voting power of all of the shares of capital stock of the corporation reasonably believed by such Proposing Person to be sufficient to elect the nominee or nominees proposed to be nominated by such stockholder (such statement, the “~~Solicitation Statement”).~~

~~For purposes of this Article I of these bylaws, the term “Proposing Person~~” shall mean the following persons: (i) the stockholder of record providing the notice of nominations or business proposed to be brought before a stockholders’ meeting, and (ii) the beneficial owner(s), if different, on whose behalf the nominations or business proposed to be brought before a stockholders’ meeting is made. For purposes of this Section 1.1 of Article I of these bylaws, the term “~~Synthetic Equity Interest” shall mean any transaction, agreement or arrangement (or series of transactions, agreements or arrangements), including, without limitation, any derivative, swap, hedge, repurchase orso-called~~ “stock borrowing” agreement or arrangement, the purpose or effect of which is to, directly or indirectly: (a) give a person or entity economic benefit and/or risk similar to ownership of shares of any class or series of capital stock of the corporation, in whole or in part, including due to the fact that such transaction, agreement or arrangement provides, directly or indirectly, the opportunity to profit or avoid a loss from any increase or decrease in the value of any shares of any class or series of capital stock of the corporation, (b) mitigate loss to, reduce the economic risk of or manage the risk of share price changes for, any person or entity with respect to any shares of any class or series of capital stock of the corporation, (c) otherwise provide in any manner the opportunity to profit or avoid a loss from any decrease in the value of any shares of any class or series of capital stock of the corporation, or (d) increase or decrease the voting power of any person or entity with respect to any shares of any class or series of capital stock of the corporation.

(3) A stockholder providing Timely Notice of nominations or business proposed to be brought before an annual meeting shall further update and supplement such notice, if necessary, so that the information (including, without limitation, the Material Ownership Interests information) provided or required to be provided in such notice pursuant to this bylaw shall be true and correct as of the record date for the meeting and as of the date that is ten business days prior to such annual


~~A-2~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

meeting, and such update and supplement shall be received by the Secretary at the principal executive offices of the corporation not later than the close of business on the fifth business day after the record date for the annual meeting (in the case of the update and supplement required to be made as of the record date), and not later than the close of business on the eighth business day prior to the date of the annual meeting (in the case of the update and supplement required to be made as of ten business days prior to the meeting).

(4) Notwithstanding anything in the second sentence of Article I, Section 1.1(b)(2) of this bylaw to the contrary, in the event that the number of directors to be elected to the Board of Directors of the corporation is increased and there is no public announcement naming all of the nominees for director or specifying the size of the increased Board of Directors made by the corporation at least ten (10) days before the last day a stockholder may deliver a notice of nomination in accordance with the second sentence of Article I, Section 1.1(b)(2), a stockholder’s notice required by this bylaw shall also be considered timely, but only with respect to nominees for any new positions created by such increase, if it shall be received by the Secretary of the corporation not later than the close of business on the tenth (10th) day following the day on which such public announcement is first made by the corporation.

~~(c)~~ ~~Other~~.

(1) Only such persons who are nominated in accordance with the provisions of this bylaw shall be eligible for election and to serve as directors and only such business shall be conducted at an annual meeting as shall have been brought before the meeting in accordance with the provisions of this bylaw. The Board of Directors or a designated committee thereof shall have the power to determine whether a nomination or any business proposed to be brought before the meeting was made in accordance with the provisions of this bylaw. If neither the Board of Directors nor such designated committee makes a determination as to whether any stockholder proposal or nomination was made in accordance with the provisions of this bylaw, the presiding officer of the annual meeting shall have the power and duty to determine whether the stockholder proposal or nomination was made in accordance with the provisions of this bylaw. If the Board of Directors or a designated committee thereof or the presiding officer, as applicable, determines that any stockholder proposal or nomination was not made in accordance with the provisions of this bylaw, such proposal or nomination shall be disregarded and shall not be presented for action at the annual meeting.

(2) Except as otherwise required by law, nothing in this Article I, Section 1.1 shall obligate the corporation or the Board of Directors to include in any proxy statement or other stockholder communication distributed on behalf of the corporation or the Board of Directors information with respect to any nominee for director or any other matter of business submitted by a stockholder.

(3) Notwithstanding the foregoing provisions of this Article I, Section 1.1, if the proposing stockholder (or a qualified representative of the stockholder) does not appear at the annual meeting to present a nomination or any business, such nomination or business shall be disregarded, notwithstanding that proxies in respect of such vote may have been received by the corporation. For purposes of this Article I, Section 1.1, to be considered a qualified representative of the proposing stockholder, a person must be authorized by a written instrument executed by such stockholder or an electronic transmission delivered by such stockholder to act for such stockholder as proxy at the meeting of stockholders and such person must produce such written instrument or electronic transmission, or a reliable reproduction of the written instrument or electronic transmission, to the presiding officer at the meeting of the stockholders.

(4) For purposes of this bylaw, “public announcement” shall mean disclosure in a press release reported by the Dow Jones News Service, Associated Press or comparable national news service or in a document publicly filed by the corporation with the Securities and Exchange Commission pursuant to Section 13, 14 or 15(d) of the Exchange Act.

(5) Notwithstanding the foregoing provisions of this bylaw, a stockholder shall also comply with all applicable requirements of the Exchange Act and the rules and regulations thereunder with respect to the matters set forth in this bylaw. Nothing in this bylaw shall be deemed to affect any rights of (i) stockholders to have proposals included in the corporation’s proxy statement pursuant to Rule~~14a-8~~ (or any successor rule) under the Exchange Act and, to the extent required by such rule, have such proposals considered and voted on at an annual meeting or (ii) the holders of any series of Preferred Stock to elect directors under specified circumstances.

~~Section 1.2~~ ~~Special Meetings~~. Except as otherwise required by statute and subject to the rights, if any, of the holders of any series of Preferred Stock, special meetings of the stockholders of the corporation may be called only by the Board of Directors acting pursuant to a resolution approved by the affirmative vote of a majority of the Directors then in office. The Board of Directors may postpone or reschedule any previously scheduled special meeting of stockholders. Only those matters set forth in the notice of the special meeting may be considered or acted upon at a special meeting of stockholders of the corporation. Nominations of persons for election to the Board of Directors of the corporation and stockholder proposals of other business shall not be brought before a special meeting of stockholders to be considered by the stockholders unless such special meeting is held in lieu of an annual meeting of stockholders in accordance with Article I, Section 1.1(a) of these bylaws, in


					~~A-3~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

which case such special meeting in lieu thereof shall be deemed an annual meeting for purposes of these bylaws and the provisions of Article I, Section 1.1(b) of these bylaws shall govern such special meeting.

~~Section 1.3~~ ~~Notice of Meetings~~. Whenever stockholders are required or permitted to take any action at a meeting, a written notice of the meeting shall be given which shall state the place, date and hour of the meeting, and, in the case of a special meeting, the purpose or purposes for which the meeting is called. Unless otherwise provided by law, the written notice of any meeting shall be given not less than ten nor more than sixty days before the date of the meeting to each stockholder entitled to vote at such meeting. If mailed, such notice shall be deemed to be given when deposited in the mail, postage prepaid, directed to the stockholder at his/her address as it appears on the records of the corporation.

~~Section 1.4~~ ~~Adjournments~~. Any meeting of stockholders, annual or special, may adjourn from time to time to reconvene at the same or some other place, and notice need not be given of any such adjourned meeting if the time and place thereof are announced at the meeting at which the adjournment is taken. At the adjourned meeting the corporation may transact any business which might have been transacted at the original meeting. If the adjournment is for more than thirty days, or if after the adjournment a new record date is fixed for the adjourned meeting, a notice of the adjourned meeting shall be given to each stockholder of record entitled to vote at the meeting.

~~Section 1.5~~ ~~Quorum~~. At each meeting of stockholders, except where otherwise provided by law or the certificate of incorporation or these bylaws, the holders of shares representing a majority of the votes entitled to be cast by the holders of the outstanding shares of stock entitled to vote at the meeting, present in person or by proxy, shall constitute a quorum. In the absence of a quorum, the stockholders so present may, by majority vote, adjourn the meeting from time to time in the manner provided in Section 1.4 of these bylaws until a quorum shall attend. Shares of its own stock belonging to the corporation or to another corporation, if a majority of the shares entitled to vote in the election of directors of such other corporation is held, directly or indirectly, by the corporation, shall neither be entitled to vote nor be counted for quorum purposes; provided, however, that the foregoing shall not limit the right of the corporation to vote stock, including but not limited to its own stock, held by it in a fiduciary capacity.

~~Section 1.6~~ ~~Organization~~. Meetings of stockholders shall be presided over by the Chairman of the Board, if any, or in his/her absence by the Vice Chairman of the Board, if any, or in his/her absence by the President, or in his/her absence by a Vice President, or in the absence of the foregoing persons by a chairman designated by the Board of Directors, or in the absence of such designation by a chairman chosen at the meeting. The Secretary shall act as secretary of the meeting, but in his/her absence the chairman of the meeting may appoint any person to act as secretary of the meeting.

~~Section 1.7~~ ~~Voting; Proxies~~. Except as otherwise provided in the certificate of incorporation or any amendment thereto, each stockholder entitled to vote at any meeting of stockholders shall be entitled to one vote for each share of stock held by him which has voting power upon the matter in question. Each stockholder entitled to vote at a meeting of stockholders may authorize another person or persons to act for him by proxy, but no such proxy shall be voted or acted upon after three years from its date, unless the proxy provides for a longer period. A duly executed proxy shall be irrevocable if it states that it is irrevocable and if, and only as long as, it is coupled with an interest sufficient in law to support an irrevocable power. A stockholder may revoke any proxy which is not irrevocable by attending the meeting and voting in person or by filing an instrument in writing revoking the proxy or another duly executed proxy bearing a later date with the Secretary of the corporation. Voting at meetings of stockholders need not be by written ballot and need not be conducted by inspectors unless the holders of shares representing a majority of the votes entitled to be cast by the holders of the outstanding shares of all classes of stock entitled to vote thereon present in person or by proxy at such meeting shall so determine. At all meetings of stockholders~~for the election of directors a plurality of the votes cast shall be sufficient to electat which a quorum is present, all corporate actions to be taken by vote of the stockholders~~ ~~shall, unless otherwise~~~~providedrequired~~ by law or by the certificate of incorporation or these bylaws, be decided by the vote of shares representing a majority of the votes entitled to be cast by the holders of the outstanding shares of stock entitled to vote thereon present in person or by proxy at the meeting.

~~Section 1.8~~ ~~Fixing Date for Determination of Stockholders of Record~~. In order that the corporation may determine the stockholders entitled to notice of or to vote at any meeting of stockholders or any adjournment thereof, or to express consent to corporate action in writing without a meeting, or entitled to receive payment of any dividend or other distribution or allotment of any rights, or entitled to exercise any rights in respect of any change, conversion or exchange of stock or for the purpose of any other lawful action, the Board of Directors may fix, in advance, a record date, which shall not be more than sixty nor less than ten days prior to any other action. If no record date is fixed: (1) the record date for determining stockholders entitled to notice of or to vote at a meeting of stockholders shall be at the close of business on the day next preceding the day on which notice is given, or, if notice is waived, at the close of business on the day next preceding the day on which the meeting is held; and (2) the record date for determining stockholders for any other purpose shall be at the close of business on the day on which the Board of Directors adopts the resolution relating thereto. A determination of stockholders of record entitled to notice of or to vote at a meeting of stockholders shall apply to any adjournment of the meeting; provided, however, that the Board of Directors may fix a new record date for the adjourned meeting.


~~A-4~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

~~Section 1.9~~ ~~List of Stockholders Entitled to Vote~~. The Secretary shall prepare and make, at least ten days before every meeting of stockholders, a complete list of the stockholders entitled to vote at the meeting, arranged in alphabetical order, and showing the address of each stockholder and the number of shares registered in the name of each stockholder. Such list shall be open to the examination of any stockholder, for any purpose germane to the meeting, during ordinary business hours, for a period at least ten days prior to the meeting, either at a place within the city where the meeting is to be held, which place shall be specified in the notice of the meeting, or, if not so specified, at the place where the meeting is to be held. The list shall also be produced and kept at the time and place of the meeting during the whole time thereof and may be inspected by any stockholder who is present. Upon the willful neglect or refusal of the directors to produce such a list at any meeting for the election of directors, they shall be ineligible for election to any office at such meeting. The stock ledger shall be the only evidence as to who are the stockholders entitled to examine the stock ledger, the list of stockholders or the books of the corporation, or to vote in person or by proxy at any meeting of stockholders.

~~Section 1.10~~ ~~Action by Consent of Stockholders~~. Unless otherwise restricted by the Certificate of Incorporation, any action required or permitted to be taken at any annual or special meeting of the stockholders may be taken without a meeting, without prior notice and without a vote, if a consent in writing, setting forth the action so taken, shall be signed by the holders of outstanding stock having not less than the minimum number of votes that would be necessary to authorize or take such action at a meeting at which all shares entitled to vote thereon were present and voted. Prompt notice of the taking of the corporate action without a meeting by less than unanimous written consent shall be given to those stockholders who have not consented in writing.

~~ARTICLE II~~

~~BOARD OF DIRECTORS~~

~~Section 2.1~~ ~~Number; Qualifications. The Board of Directors shall consist of one or more members, the number thereof to be determined from time to time by resolution of the Board of Directors. Directors need not be stockholders.~~

~~Section 2.2~~ ~~Election; Resignation; Removal; Vacancies~~.The Board of Directors shall initially consist of the persons named as Directors by the Incorporator, and each Director so elected shall hold office until the first annual meeting of stockholders or until his/her successor is elected and qualified.At the first annual meeting of stockholders and at each annual meeting thereafter, the stockholders shall elect Directors each of whom shall hold office for a term of one year or until his/her successor is elected and qualified.At any meeting of stockholders for the election of Directors at which a quorum is present, each Director shall be elected by a majority of the votes cast; provided that, if the election is contested, the Directors shall be elected by a plurality of the votes cast. An election shall be contested if the number of nominees for Director~~exceeds the number of Directors to be elected, as determined by the Board of Directors. For purposes of this Section~~ 2.2, a majority of votes cast shall mean that the number of votes cast “for” a Director’s election exceeds the number of votes cast “against” that Director’s election (with abstentions and broker~~non-votes~~ ~~not counted as a vote cast either “for” or “against” such Director’s election).~~ ~~Any Director may resign at any time upon written notice(including by electronic transmission)~~ ~~to the corporation; such resignation shall take effect upon delivery, unless the resignation specifies a later effective date or time or an effective date or time determined upon the happening of an event or events. Any vacancy occurring in the Board of Directors for any cause may be filled by a majority of the remaining members of the Board of Directors, although such majority is less than a quorum, or by a~~~~pluralitymajority~~ of the votes cast at a meeting of stockholders, and each Director so elected shall hold office until the expiration of the term of office of the Director whom he has replaced or until his/her successor is elected and qualified.

~~Section 2.3~~ ~~Regular Meetings~~. Regular meetings of the Board of Directors may be held at such places within or without the State of Delaware and at such times as the Board of Directors may from time to time determine, and if so determined notices thereof need not be given.

~~Section 2.4~~ ~~Special Meetings~~. Special meetings of the Board of Directors may be held at any time or place within or without the State of Delaware whenever called by the President, any Vice President, the Secretary, or by any member of the Board of Directors. Reasonable notice thereof shall be given by the person or persons calling the meeting, not later than the second day before the date of the special meeting.

~~Section 2.5~~ ~~Telephonic Meetings Permitted~~. Members of the Board of Directors, or any committee designated by the Board, may participate in a meeting of such Board or committee by means of conference telephone or similar communications equipment by means of which all persons participating in the meeting can hear each other, and participation in a meeting pursuant to this bylaw shall constitute presence in person at such meeting.

~~Section 2.6~~ ~~Quorum; Vote Required for Action~~. At all meetings of the Board of Directors a majority of the directors then in office shall constitute a quorum for the transaction of business. Except in cases in which the certificate of incorporation or these


					~~A-5~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

~~bylaws otherwise provide, the vote of a majority of the directors present at a meeting at which a quorum is present shall be the act of the Board of Directors.~~

~~Section 2.7~~ ~~Organization~~. Meetings of the Board of Directors shall be presided over by the Chairman of the Board, if any, or in his/her absence by the Vice Chairman of the Board, if any, or in his/her absence by the President, or in their absence by a chairman chosen at the meeting. The Secretary shall act as secretary of the meeting, but in his/her absence the chairman of the meeting may appoint any person to act as secretary of the meeting.

~~Section 2.8~~ ~~Informal Action by Directors~~. Unless otherwise restricted by the certificate of incorporation or these bylaws, any action required or permitted to be taken at any meeting of the Board of Directors, or of any committee thereof, may be taken without a meeting if all members of the Board or such committee, as the case may be, consent thereto in writing, and the writing or writings are filed with the minutes of proceedings of the Board or committee.

~~ARTICLE III~~

~~COMMITTEES~~

~~Section 3.1~~ ~~Committees~~. The Board of Directors may designate one or more committees, each committee to consist of one or more of the directors of the corporation. The Board may designate one or more directors as alternate members of any committee, who may replace any absent or disqualified member at any meeting of the committee. In the absence or disqualification of a member of the committee, the member or members thereof present at any meeting and not disqualified from voting, whether or not he or they constitute a quorum, may unanimously appoint another member of the Board of Directors to act at the meeting in place of any such absent or disqualified member. Any such committee, to the extent provided in the resolution of the Board of Directors, shall have and may exercise all the powers and authority of the Board of Directors in the management of the business and affairs of the corporation, and may authorize the seal of the corporation to be affixed to all papers which may require it, but no such committee shall have the power or authority in reference to amending the Amended and Restated Certificate of Incorporation, as it may be amended from time to time (the “Certificate of Incorporation”) (except that any such committee may, to the extent authorized in the resolution or resolutions providing for the issuance of shares of Preferred Stock adopted by the Board of Directors pursuant to Article Fourth of the Certificate of Incorporation, fix any of the preferences or rights of such shares relating to dividends, redemption, dissolution, any distribution of the assets of the corporation or the conversion into, or the exchange of such shares for, shares of any other class or classes or any other series of the same or any other class or classes of stock of the corporation), adopting an agreement of merger or consolidation under Sections 251 or 252 of the General Corporation Law of the State of Delaware, recommending to the stockholders the sale, lease or exchange of all or substantially all of the corporation’s property and assets, recommending to the stockholders a dissolution of the corporation or a revocation of a dissolution, or amending these Bylaws; and unless the resolution or the Certificate of Incorporation expressly so provides, no such committee shall have the power or authority to declare a dividend, to authorize the issuance of stock, or to adopt a certificate of ownership and merger pursuant to Section 253 of the General Corporation Law of the State of Delaware.

~~Section 3.2~~ ~~Committee Rules~~. Unless the Board of Directors otherwise provides, each committee designated by the Board may make, alter and repeal rules for the conduct of its business. In the absence of such rules each committee shall conduct its business in the same manner as the Board of Directors conducts its business pursuant to Article II of these Bylaws.

~~ARTICLE IV~~

~~OFFICERS~~

~~Section 4.1~~ ~~Executive Officers; Election; Qualifications; Term of Office; Resignation; Removal; Vacancies~~. The Board of Directors shall choose a President and Secretary, and it may, if it so determines, choose a Chairman of the Board and a Vice Chairman of the Board from among its members. The Board of Directors may also choose one or more Vice Presidents, one or more Assistant Secretaries, a Treasurer and one or more Assistant Treasurers. Each such officer shall hold office until the first meeting of the Board of Directors after the annual meeting of stockholders next succeeding this election, and until his/her successor is elected and qualified or until his/her earlier resignation or removal. Any officer may resign at any time upon written notice~~(including by electronic transmission)~~ ~~to the corporation; such resignation shall take effect upon delivery, unless the resignation specifies a later effective date or time or an effective date or time determined upon the happening of an eventor events~~. The Board of Directors may remove any officer with or without cause at any time, but such removal shall be without prejudice to the contractual rights of such officer, if any, with the corporation. Any number of offices may be held by the same person. Any vacancy occurring in any office of the corporation by death, resignation, removal or otherwise may be filled for the unexpired portion of the term by the Board of Directors at any regular or special meeting.


~~A-6~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

~~Section 4.2~~ ~~Powers and Duties of Executive Officers~~. The officers of the corporation shall have such powers and duties in the management of the corporation as may be prescribed by the Board of Directors and, to the extent not so provided, as generally pertain to their respective offices, subject to the control of the Board of Directors. The Board of Directors may require any officer, agent or employee to give security for the faithful performance of his/her duties.

~~ARTICLE V~~

~~STOCK~~

~~Section 5.1~~ ~~Certificates~~. The Board may provide by resolution or resolutions that some or all of any or all classes or series of the stock of the Company shall be uncertificated shares. Certificates, if any, representing shares of stock of the Company will be in such form as is determined by the Board, subject to applicable legal requirements. Each such certificate shall be numbered and shall be signed by or in the name of the corporation by the Chairman or Vice Chairman of the Board of Directors, if any, or the President or a Vice President, and by the Treasurer or an Assistant Treasurer, or the Secretary or an Assistant Secretary, of the corporation, certifying the number of shares owned by him in the corporation. Any of or all the signatures on the certificate may be a facsimile. In case any officer, transfer agent, or registrar who has signed or whose facsimile signature has been placed upon a certificate shall have ceased to be such officer, transfer agent, or registrar before such certificate is issued, it may be issued by the corporation with the same effect as if he were such officer, transfer agent, or registrar at the date of issue. Records shall be kept of the amount of stock of the corporation issued and outstanding, the manner in which and the time when such stock was paid for, the respective names, alphabetically arranged, and the addresses, of the persons, firms or corporations owning of record the stock represented by certificates for stock of the corporation, the number, class and series of shares represented by such certificates, respectively, the time when each became an owner of record thereof, and the respective dates of such certificates, and in case of cancellation, the respective dates of cancellation.

~~Section 5.2~~ ~~Lost, Stolen or Destroyed Stock Certificates; Issuance of New Certificates~~. The corporation may issue a new certificate of stock in the place of any certificate theretofore issued by it, alleged to have been lost, stolen or destroyed, and the corporation may require the owner of the lost, stolen or destroyed certificate, or his/her legal representative, to give the corporation a bond sufficient to indemnify it against any claim that may be made against it on account of the alleged loss, theft or destruction of any such certificate or the issuance of such new certificate.

~~Section 5.3~~ ~~Transfers of Stock~~. Transfers of shares shall be made upon the books of the Company (i) only by the holder of record thereof, or by a duly authorized agent, transferee or legal representative and (ii) in the case of certificated shares, upon the surrender to the Company of the certificate or certificates for such shares. No transfer shall be made that is inconsistent with the provisions of applicable law. The person in whose name shares of stock stand on the books of the corporation shall be deemed the owner thereof for all purposes as regards the corporation. Whenever any transfer of shares shall be made for collateral security and not absolutely, such fact shall be so expressed in the entry of transfer if, when the certificate of certificates shall be presented to the corporation for transfer, both the transferor and the transferee request the corporation to do so.

~~Section 5.4~~ ~~Regulations Concerning Transfer of Stock~~. The Board of Directors may make such rules and regulations as it may deem expedient, not inconsistent with these Bylaws, concerning the issue, transfer and registration of certificates for stock of the corporation. The Board of Directors may appoint, or authorize any officer or officers to appoint, one or more transfer agents and one or more registrars, and may require all certificates for stock to bear the signature or signatures of any of them.

~~ARTICLE VI~~

~~INDEMNIFICATION OF DIRECTORS,~~

~~OFFICERS, EMPLOYEES AND AGENTS~~

~~Section 6.1~~ ~~Right to Indemnification~~. The corporation shall indemnify and hold harmless, to the fullest extent permitted by applicable law as it presently exists or may hereafter be amended, any person who was or is made or is threatened to be made a party or is otherwise involved in any action, suit, or proceeding, whether civil, criminal, administrative, or investigative (a “proceeding”) by reason of the fact that he, or a person for whom he is the legal representative, is or was a director, officer, employee or agent of the corporation or is or was serving at the request of the corporation as a director, officer, employee or agent of another corporation or of a partnership, joint venture, trust, enterprise or~~non-profit~~ entity, including service with respect to employee benefit plans, against all liability and loss suffered and expenses reasonably incurred by such person. The corporation shall indemnify a person in connection with a proceeding initiated by such person only if the proceeding was authorized by the Board of Directors of the corporation.


					~~A-7~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

~~Section 6.2~~ ~~Prepayment of Expenses~~. The corporation shall pay the expenses incurred in defending any proceeding in advance of its final disposition, provided, however, that the payment of expenses incurred by a director or officer in his/her capacity as a director or officer (except with regard to service to an employee benefit plan or~~non-profit~~ organization) in advance of the final disposition of the proceeding shall be made only upon receipt of an undertaking by the director or officer to repay all amounts advanced if it should be determined that the director or officer is not entitled to be indemnified under this Article VI or otherwise.

~~Section 6.3~~ ~~Claims~~. If a claim for indemnification or payment of expenses under this Article VI is not paid in full within 90 days after a written claim therefor has been received by the corporation, the claimant may file suit to recover the unpaid amount of such claims and, if successful in whole or in part, shall be entitled to be paid the expense of prosecuting such claim. In any such action the corporation shall have the burden of proving that the claimant was not entitled to the requested indemnification or payment of expenses under applicable law.

~~Section 6.4~~ ~~Non-Exclusivity~~ ~~of Rights~~. The rights conferred on any person by this Article shall not be exclusive of any other rights which such person may have or hereafter acquire under any statute, provision of the Certificate of Incorporation, these Bylaws, agreement, vote of stockholders or disinterested directors or otherwise.

~~Section 6.5~~ ~~Amendment or Repeal~~. Any repeal or modification of the foregoing provisions of this Article VI shall not adversely affect any right or protection of a director, officer or employee of the corporation in respect of any act or omission occurring prior to the time of such repeal or modification.

~~ARTICLE VII~~

~~MISCELLANEOUS~~

~~Section 7.1~~ ~~Fiscal Year. The fiscal year of the corporation shall be determined by resolution of the Board of Directors.~~

~~Section 7.2~~ ~~Seal~~. The Board of Directors may, but need not, adopt a corporate seal. If adopted, the corporate seal shall have the name of the corporation inscribed thereon and shall be in such form as may be approved from time to time by the Board of Directors.

~~Section 7.3~~ ~~Waiver of Notice of Meetings of Stockholders, Directors and Committees~~. Any written waiver of notice, signed by the person entitled to notice, whether before or after the time stated therein, shall be deemed equivalent to notice. Attendance of a person at a meeting shall constitute a waiver of notice of such meeting, except when the person attends a meeting for the express purpose of objecting, at the beginning of the meeting, to the transaction of any business because the meeting is not lawfully called or convened. Neither the business to be transacted at, nor the purpose of any regular or special meeting of the stockholders, directors, or members of a committee of directors need be specified in any written waiver of notice.

~~Section 7.4~~ ~~Interested Directors; Quorum~~. No contract or transaction between the corporation and one or more of its directors or officers, or between the corporation and any other corporation, partnership, association, or other organization in which one or more of its directors or officers are directors or officers, or have a financial interest, shall be void or voidable solely for this reason, or solely because the director or officer is present at or participates in the meeting of the Board or committee thereof which authorizes the contract or transaction, or solely because his/her or their votes are counted for such purpose, if: (1) the material facts as to his/her relationship or interest and as to the contract or transaction are disclosed or are known to the Board of Directors or the committee, and the Board or committee in good faith authorizes the contract or transaction by the affirmative votes of a majority of the disinterested directors, even though the disinterested directors be less than a quorum; or (2) the material facts as to his/her relationship or interest and as to the contract or transaction are disclosed or are known to the stockholders entitled to vote thereon, and the contract or transaction is specifically approved in good faith by vote of the stockholders; or (3) the contract or transaction is fair as to the corporation as of the time it is authorized, approved or ratified, by the Board of Directors, a committee thereof, or the stockholders. Common or interested directors may be counted in determining the presence of a quorum at a meeting of the Board of Directors or of a committee, which authorizes the contract or transaction.

~~Section 7.5~~ ~~Form of Records~~. Any records maintained by the corporation in the regular course of its business, including its stock ledger, books of account, and minute books, may be kept on, or be in the form of, punch cards, magnetic tape, photographs, microphotographs, or any other information storage device, provided that the records so kept can be converted into clearly legible form within a reasonable time. The corporation shall so convert any records so kept upon the request of any person entitled to inspect the same.


~~A-8~~

~~2020 PROXY STATEMENT~~ ~~Exhibit A~~

~~Section 7.6~~ ~~Amendment of Bylaws~~. These Bylaws may be altered or repealed, and new bylaws made, by the Board of Directors, but the stockholders may make additional bylaws and may alter and repeal any bylaws whether adopted by them or otherwise.

~~* * *~~


					~~A-9~~

ARROWHEAD PHARMACEUTICALS, INC. 177 EAST COLORADO BLVD, SUITE 700 PASADENA, CA 91105 VOTE BY INTERNET Before The Meeting - Go to www.proxyvote.com Use the Internet to transmit your voting instructions and for electronic delivery of information up until 11:59 p.m. Eastern Time the day before the~~cut-off~~ date or meeting date. Have your proxy card in hand when you access the web site and follow the instructions to obtain your records and to create an electronic voting instruction form. During The Meeting - Go to www.virtualshareholdermeeting.com/ARWR2020 You may attend the meeting via the Internet and vote during the meeting. Have the information that is printed in the box marked by the arrow available and follow the instructions. VOTE BY PHONE -~~1-800-690-6903~~ ~~Use any touch-tone telephone to transmit your voting instructions up until 11:59 p.m. Eastern Time the day before thecut-off~~ date or meeting date. Have your proxy card in hand when you call and then follow the instructions. VOTE BY MAIL Mark, sign and date your proxy card and return it in the postage-paid envelope we have provided or return it to Vote Processing, c/o Broadridge, 51 Mercedes Way, Edgewood, NY 11717. TO VOTE, MARK BLOCKS BELOW IN BLUE OR BLACK INK AS FOLLOWS: E88884-P32218 KEEP THIS PORTION FOR YOUR RECORDS THIS PROXY CARD IS VALID ONLY WHEN SIGNED AND DATED. DETACH AND RETURN THIS PORTION ONLY ARROWHEAD PHARMACEUTICALS, INC. The Board of Directors recommends you vote FOR ALL the following director nominees: For All Withhold All Except For All 1. Election of Directors Nominees: 01) Christopher Anzalone 02) Marianne De Backer 03) Mauro Ferrari 04) Douglass Given 05) Michael S. Perry 06) William Waddill To withhold authority to vote for any individual nominee(s), mark “For All Except” and write the number(s) of the nominee(s) on the line below. The Board of Directors recommends you vote FOR proposals 2, 3, and 4: 2. To approve, in an advisory~~(non-binding)~~ ~~vote, the compensation paid to the Company’s named executive officers, as disclosed pursuant to Item 402 of RegulationS-K,~~ including the compensation tables and narrative discussion. 3. To approve an amendment to the Company’s Amended and Restated Bylaws to implement a majority vote standard in uncontested elections of directors. 4. To ratify the selection of Rose, Snyder & Jacobs LLP as independent auditors of the Company for the fiscal year ending September 30, 2020. For Against Abstain NOTE: Such other business as may properly come before the meeting or any adjournment thereof. Please sign exactly as your name(s) appear(s) hereon. When signing as attorney, executor, administrator, or other fiduciary, please give full title as such. Joint owners should each sign personally. All holders must sign. If a corporation or partnership, please sign in full corporate or partnership name by authorized officer. Signature [PLEASE SIGN WITHIN BOX] Date Signature (Joint Owners) Date

~~Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting: The Notice and Proxy Statement and Form10-K~~ are available at www.proxyvote.com. E88885-P32218 ARROWHEAD PHARMACEUTICALS, INC. Annual Meeting of Stockholders March 19, 2020 10:00 AM, PT This proxy is solicited by the Board of Directors The stockholder(s) hereby appoint(s) Christopher Anzalone and Patrick O’Brien or either of them, as proxies, each with the power to appoint his substitute, and hereby authorize(s) them to represent and to vote, as designated on the reverse side of this ballot, all of the shares of Common Stock of ARROWHEAD PHARMACEUTICALS, INC. that the stockholder(s) is/are entitled to vote at the Annual Meeting of Stockholders to be held at 10:00 AM, PT on March 19, 2020, online at WWW.VirtualShareholderMeeting.com/ARWR2020, and any adjournment or postponement thereof. This proxy, when properly executed, will be voted in the manner directed herein. If no such direction is made, this proxy will be voted in accordance with the Board of Directors’ recommendations. Continued and to be signed on reverse side


Board Diversity Matrix (As of January 30, 2023)
Total Number of Directors	#8
	Female	Male	Non-Binary	Did Not Disclose Gender
Part I: Gender Identity
Directors	2	6	0	0
Part II: Demographic Background
African American or Black	0	1	0	0
Alaskan Native or Native American	0	0	0	0
Asian	0	0	0	0
Hispanic or Latinx	0	0	0	0
Native Hawaiian or Pacific Islander	0	0	0	0
White	2	5	0	0
Two or More Races or Ethnicities	0	0	0	0
LGBTQ+	0
Did Not Disclose Demographic Background	0


Name & Position	2020 Annual Fee (1) (effective 1/1/20)		2020 Stock Award (2)		2020 Grant Date Value		2019 Annual Fee (3) (effective 1/1/19)		2019 Stock Award (2)		2019 Grant Date Value
Douglass Given Chairman	$	85,000		8,000	$	507,440	$	80,000		36,000	$	447,120
Michael S. Perry Lead Director	$	80,000		8,000	$	507,440	$	80,000		36,000	$	447,120
Mauro Ferrari Director (4)	$	120,000		7,500	$	475,725	$	135,556		8,429	$	194,738
William Waddill Director	$	75,000		7,500	$	475,725	$	70,000		30,000	$	372,600
Marianne De Backer Director (5)	$	70,000		7,500	$	475,725	$	0		5,000	$	336,600


Name	Fee Earned or Paid in Cash ($)		Stock Awards ($) (1) (2)		Total ($)
Douglass Given	$	78,438	$	447,120	$	525,558
Michael S. Perry	$	75,813	$	447,120	$	522,933
Mauro Ferrari (3)	$	107,431	$	194,738	$	302,169
William Waddill	$	64,375	$	372,600	$	436,975
Marianne De Backer (4)		N/A		N/A		N/A


Named Executive Officer	2019 Base Salary			2018 Base Salary			Percentage Adjustment
Christopher Anzalone President & CEO		$	682,500		$	650,000		5	%
Bruce Given Chief Operating Officer		$	500,000		$	455,000		10	%
Kenneth Myszkowski Chief Financial Officer		$	430,000		$	400,000		8	%
Patrick O’Brien General Counsel		$	426,400		$	410,000		4	%
Zhen Li (1) Senior Vice President Chemistry &Non-Clinical Development		$	390,000		$	300,000		30	%


Named Executive Officer	2019 Target Annual Incentive Award Opportunity (as a percentage of base salary)			2018 Target Annual Incentive Award Opportunity (as a percentage of base salary)
Dr. Anzalone		100	%		100	%
Dr. Given		70	%		70	%
Mr. Myszkowski		45	%		45	%
Mr. O’Brien		45	%		45	%
Dr. Li (1)		40	%		40	%


Named Executive Officer	Target Annual Incentive Award Opportunity (as a percentage of base salary)			Actual Annual Incentive Award (as a percentage of base salary)			Actual Annual Incentive Award ($)
Dr. Anzalone		100	%		226	%		$	1,540,000
Dr. Given		70	%		170	%		$	850,000
Mr. Myszkowski		45	%		59	%		$	251,550
Mr. O’Brien		45	%		59	%		$	249,444
Dr. Li (1)		40	%		0	%		$	0


Named Executive Officer	Restricted Stock Unit Awards (number of shares)		Restricted Stock Unit Grant Date Fair Values ($)
Mr. Given		210,000		$	2,608,200
Mr. Myszkowski		85,000		$	1,055,700
Mr. O’Brien		70,000		$	869,400
Dr. Li (1)		75,000		$	931,500


Name and Principal Position	Year		Salary ($)		Stock Awards (1) ($)			Non-Equity Incentive Plan Compensation (2) ($)		All Other Compensation (3) ($)		Total
Christopher Anzalone President and Chief Executive Officer		2019		674,375		—	(4)		1,540,000		1,889		2,216,264
		2018		643,012		—	(5)		975,000		1,889		1,619,901
		2017		616,068		537,900	(6)		715,357		1,889		1,871,214
Kenneth Myszkowski Chief Financial Officer		2019		422,500		1,055,700			251,550		11,799		1,741,549
		2018		384,841		276,000			180,000		12,177		853,018
		2017		336,099		224,750			152,713		11,809		725,371
Bruce D. Given Chief Operating Officer		2019		488,750		2,608,200			850,000		11,799		3,958,759
		2018		450,362		644,000			445,900		11,799		1,552,061
		2017		432,250		589,000			351,340		11,599		1,384,189
Patrick O’Brien General Counsel		2019		422,300		869,400			249,444		11,799		1,552,943
		2018		406,196		220,800			184,500		11,799		823,295
		2017		390,988		224,750			177,653		11,599		804,990
Zhen Li (7) Senior Vice President, Chemistry and Non- Clinical Development		2019		150,257		931,500			—		4,236		1,085,993
		2018		287,462		239,200			150,000		9,462		686,124
		2017		247,448		131,750			120,000		6,798		505,996


			Estimated Future Payouts UnderNon-Equity Incentive Plan Awards (1)			Estimated Future Payouts Under Equity Incentive Plan Awards (2)		All Other Stock Awards: Number of Shares of Stock or Units (#) (3)		Grant Date Fair Value
Name	Grant Date		Target			Target				Grant Date Fair Value
Christopher Anzalone
Cash Bonus				$	682,500		—		—			—
PRSUs (4)		1/1/2019			—		200,000		—			—
PRSUs (4)		1/1/2019			—		200,000		—			—
PRSUs (4)		1/1/2019			—		200,000		—			—
Kenneth Myszkowski
Cash Bonus				$	193,500		—		—			—
RSUs		1/1/2019			—		—		85,000		$	1,055,700
Bruce D. Given
Cash Bonus				$	350,000		—		—			—
RSUs		1/1/2019			—		—		210,000		$	2,608,200
Patrick O’Brien
Cash Bonus				$	191,880		—		—			—
RSUs		1/1/2019			—		—		70,000		$	869,400
Zhen Li
Cash Bonus				$	156,000		—		—			—
RSUs		1/1/2019			—		—		75,000		$	931,500


			Option Awards								Stock Awards
Name	Grant Date		Number of Securities Underlying Unexercised Options (# Exercisable) (1)		Number of Securities Underlying Unexercised Options (# Unexercisable)		Option Exercise Price ($)		Option Expiration Date		Number of Shares or Units of Stock That Have Not Vested (#) (3)		Market Value of Shares or Units of Stock That Have Not Vested ($) (4)		Equity Incentive Plan Awards: Number of Unearned Shares or Units of Stock That Have Not Vested (#) (2)		Equity Incentive Plan Awards: Market Value of Unearned Shares or Units of Stock That Have Not Vested ($) (4)
Christopher Anzalone		3/4/2010		56,325		—		5.20		3/4/2020		—		—		—		—
		8/16/2010		50,000		—		9.90		8/16/2020		—		—		—		—
		10/21/2011		15,000		—		4.60		10/21/2021		—		—		—		—
		2/16/2012		170,000		—		5.19		2/16/2022		—		—		—		—
		9/28/2012		40,624		—		2.62		9/28/2022		—		—		—		—
		5/6/2013		159,928		—		2.01		5/6/2023		—		—		—		—
		9/21/2013		69,991		—		4.75		9/21/2023		—		—		—		—
		2/6/2014		60,000		—		14.54		2/6/2024		—		—		—		—
		3/6/2015		300,000		—		7.75		3/6/2025		—		—		—		—
		1/1/2016		73,333		6,667		6.15		1/1/2026		—		—		—		—
		1/1/2018		—		—		—		—		—		—		333,333		6,389,994
		1/1/2019		—		—		—		—		—		—		600,000		16,908,000
Kenneth Myszkowski		8/16/2010		12,000		—		9.90		8/16/2020		—		—		—		—
		2/16/2012		48,000		—		5.19		2/16/2022		—		—		—		—
		2/6/2014		50,000		—		14.54		2/6/2024		—		—		—		—
		3/6/2015		50,000		—		7.75		3/6/2025		—		—		—		—
		1/1/2016		36,666		3,334		6.15		1/1/2026		—		—		—		—
		1/1/2018		—		—		—		—		56,250		1,585,125		—		—
		1/1/2019		—		—		—		—		85,000		2,395,300		—		—
Bruce D. Given		10/26/2011		30,000		—		5.20		10/26/2021		—		—		—		—
		2/16/2012		110,000		—		5.19		2/16/2022		—		—		—		—
		9/21/2013		40,000		—		4.75		9/21/2023		—		—		—		—
		2/6/2014		50,000		—		14.54		2/6/2024		—		—		—		—
		3/6/2015		60,000		—		7.75		3/6/2025		—		—		—		—
		1/1/2016		55,000		5,000		6.15		1/1/2026		—		—		—		—
		1/1/2018		—		—		—		—		131,250		3,698,625		—		—
		1/1/2019		—		—		—		—		210,000		5,917,800		—		—
Patrick O’Brien		12/2/2014		90,000		—		5.22		12/2/2024		—		—		—		—
		1/1/2016		55,000		5,000		6.15		1/1/2026		—		—		—		—
		1/1/2018		—		—		—		—		45,000		1,268,100		—		—
		1/1/2019		—		—		—		—		70,000		1,972,600		—		—
Zhen Li (5)		—		—		—		—		—		—		—		—		—


Triggering Event	Salary ($)		Benefits ($)		Stock Awards (1)($)		Option Awards (1)($)		Total
Termination by Employer without Cause
Christopher Anzalone (2)		56,875		1,888		—		—		58,673
Kenneth Myszkowski		107,500		8,619		—		—		116,119
Bruce D. Given		—		—		—		—		—
Patrick O’Brien		—		—		—		—		—
Zhen Li (3)		N/A		N/A		N/A		N/A		N/A
Change in Control
Christopher Anzalone		—		—		—		—		—
Kenneth Myszkowski		107,500		8,619		3,980,425		73,448		4,169,992
Bruce D. Given		—		—		9,616,425		110,150		9,726,575
Patrick O’Brien		—		—		3,240,700		110,150		3,350,850
Zhen Li (3)		N/A		N/A		N/A		N/A		N/A
Involuntary Termination Following a Change in Control
Christopher Anzalone		56,875		1,888		26,301,324		146,874		26,506,961
Patrick O’Brien		213,200		—		—		—		213,200


	Year Ended September 30,
	2019		2018
Audit fees (1)	$	231,325	$	194,000
Audit-related fees (2)		17,000		59,500
Tax Fees		—		—
All other fees		—		—
Total	$	248,325	$	253,500



	Number and Percentage of Shares Beneficially Owned (1)
	Shares		Percentage
5% Beneficial Owners
BlackRock Inc (2) 55 East 52nd Street, New York, NY 10055		14,869,280		14.6	%
The Vanguard Group (3) 100 Vanguard Blvd., Malvern, PA 19355		10,844,571		10.7	%

Executive Officers and Directors
Christopher Anzalone (4)		2,350,780		2.3	%
Kenneth Myszkowski (5)		354,402		*
Bruce D. Given (6)		713,993		*
Patrick O’Brien (7)		255,875		*
Douglass Given		172,925		*
Michael S. Perry (8)		113,000		*
Mauro Ferrari (9)		26,900		*
William Waddill		46,500		*
Marianne De Backer		—		*
All Executive Officers and Directors as a group (9 persons) (10)		4,034,375		4.0	%

Douglass Given, MD
~~Chairman~~
Board Chair

Age: 67
70
Director since:2010
Serves on:
•Science Committee

Experience and Expertise
Dr. Given ~~is Chairman of the Board. He~~ has been ~~a director of the Company since 2010. Doug is~~ Managing Partner at Health2047 Capital Partners ~~LLC.~~LLC, a healthcare-focused venture capital firm, since 2018. He served as Health2047 ~~Inc.’s~~lnc.'s Chief Executive Officer from its founding in ~~August~~ 2015 until ~~January~~ 2018. ~~Previously,~~ Dr. Given has spent more than ~~a decade~~two decades in venture capital as an Investment Partner and General Partner at life sciences investor Bay City Capital LLC participating in five sequential life sciences general funds and two sector-specific ~~funds. He~~funds; he was associated with the partnership from ~~1999 to 2015. A~~1999-2015. Dr. Given is a physician and medical ~~scientist by background, Dr. Given~~scientist. Since 1983, he has been a global corporate and operating executive at Lilly, Monsanto, Schering Plough and Mallinckrodt, and a serial ~~entrepreneur, as well as a venture capitalist.~~entrepreneur. In addition to a number of private companies, heDr. Given led three public ~~biotechnology and~~ biopharmaceutical companies as CEO.
Dr. Given has served on more than 20 public and private boards. He is currently our Board Chair, a ~~director~~Director at Health2047 ~~Inc., board chair at Akiri~~ Inc., Managing Partner at G5GS Partners LLC, and serves on the board at First Mile Care ~~Inc.~~Inc, BrYet Health Ltd, Visirna Therapeutics, and Vivaldi Biosciences Inc. He serves onin advisory ~~boards at~~roles on the University of Chicago Pritzker School of Medicine, and Biological Sciences Division Council (former Chair), Johns Hopkins Bloomberg School of Public Health, ~~Stanford Medicine, Stanford Institute for Economic Policy~~Health Advisory Board.
Dr. Given received MD and PhD degrees from the University of Chicago, a MBA from the Wharton School at the University of Pennsylvania, and was a Clinical and Research ~~(SIEPR),~~Fellow in internal medicine and ~~The Houston Methodist Research Institute.~~
infectious diseases at Massachusetts General Hospital and Harvard Medical School.

Qualifications
Dr. Given’s qualifications to serve on the Board include his extensive experience as a physician scientist, in finance and business transactions, particularly investments in the life sciences industry, as well as directorship roles in biopharmaceutical companies. Dr. Given also has had significant leadership roles, including CEO of several biotech companies and Senior Vice President, at several large pharmaceutical companies.