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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.     )

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

Check the appropriate box:

CONSTELLATION 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):

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215 First Street, Suite 200

Cambridge MA 02142

NOTICE OF 20202021 ANNUAL MEETING OF STOCKHOLDERS

To Be Held on Wednesday, June 4, 20202, 2021

Online at www.proxydocs.com/CNST

Dear Stockholders:

You are cordially invited to virtually attend the 20202021 annual meeting of stockholders or the Annual Meeting,(the “Annual Meeting”) of Constellation Pharmaceuticals, Inc. (the “Company”), which is scheduled towill be held on Thursday,Wednesday, June 4, 20202, 2021 at 8:00 a.m., Eastern time.  To support the health and well-being of our stockholders, employees and directors in light of the recent novel coronavirus (“COVID-19”) outbreak, the meetingTime.  The Annual Meeting will be held viaexclusively online as a virtual meeting.  You will be able to attend and participate in the Internet atAnnual Meeting virtually by visiting www.proxydocs.com/CNST.CNST, where you will be able to view the meeting and vote your shares and submit questions during the meeting.  There will be no physical meeting, and you will not be able to attend the Annual Meeting in person.

Only stockholders who owned shares of our common stock at the close of business on April 6, 2020 can5, 2021 (the “Record Date”) are entitled to notice of and to vote at the Annual Meeting or any adjournment that may take place. At the Annual Meeting, the stockholders will be asked to consider and vote on the following matters:

As noted above, our Annual Meeting will be a “virtual meeting” of stockholders, which will be conducted exclusively via the Internet. There will not be a physical meeting location, and stockholders will not be able to attend the Annual Meeting in person. This means that you can attend the Annual Meeting online, vote your shares during the online meeting and submit questions before the virtual meeting by visiting www.proxydocs.com/CNST.

In order to attend the meeting online and vote your shares electronically during the meeting, you must register in advance at www.proxydocs.com/CNST prior to the deadline of June 2, 2020 at 5:00 p.m., Eastern time.  Upon completing your registration, you will receive further instructions via email, including your unique links that will allow you to access the meeting and will permit you to submit questions. Further information about how to attend the Annual Meeting online, vote your shares and submit questions is included in the accompanying proxy statement.

You can find more information, including the nominees foreach director nominee, in the attached proxy statement for the Annual Meeting, which is available for viewing, printing and downloading at www.proxydocs.com/CNST. The board of directorsAs outlined in the attached proxy statement, the Board recommends that you vote “FOR” each of the Class II directors (Proposal 1)Proposals 1, 2, and “FOR” the ratification of the appointment of the proposed independent registered public accounting firm (Proposal 2) as outlined4, and for an executive compensation advisory vote every “ONE YEAR” in the attached proxy statement.Proposal 3.

To participate in the Annual Meeting virtually, including to vote your shares electronically and submit questions during the meeting, you must register in advance at www.proxydocs.com/CNST prior to the deadline of May 31, 2021 at 5:00 p.m., Eastern Time.  Upon completing your registration, you will receive further instructions via email, including your unique link that will allow you to access the meeting and submit questions during the meeting.

We are pleased to comply with the SECSecurities and Exchange Commission’s “notice and access” rules that allow companies to distribute their proxy materials over the Internet under the “notice and access” rules of the Securities and Exchange Commission. As a result,Internet. Accordingly, we are sending to our stockholders a Notice of Internet Availability of Proxy Materials or the Notice(the “Notice of Availability,Availability”), instead of a paper copy of this proxy statement and our annual report for the fiscal year ended December 31, 2019, or the 20192020 (the “2020 Annual Report.Report”). We

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will mail the Notice of Availability on

or about April 24, 2020, and the Notice of Availability23, 2021, which contains instructions on how to access our proxy materials over the Internet. The Notice of Availability also contains instructions on how each of our stockholders can receive a paper copy of our proxy materials, including the proxy statement, our 20192020 Annual Report, and a form of proxy card.

We cordially invite all stockholders to virtually attendYour vote is important regardless of the Annual Meeting online. Stockholdersnumber of record at the close of business on April 6, 2020, the record date for the Annual Meeting, are entitled to notice of, and to vote online at, the Annual Meeting or any adjournment or postponement thereof.shares you own. Whether or not you expect to virtually attend the Annual Meeting online, please vote your shares to ensure your representation and the presence of a quorum at the Annual Meeting. If you are a stockholder of record, you may vote your shares on the Internet by visiting www.proxydocs.com/CNST, and clicking on the “Vote Now” button, by telephone by calling 855-673-0643 and following the recorded instructions, or by completing, signing, dating, and returning a proxy card. Your vote is important regardless of the number of shares you own. If you mail your proxy card or vote by telephone or the Internet, and you may still attend the Annual Meeting online. Your proxy is revocable in accordance with the procedures set forth in the proxy statement.

If your shares are held in “street name,” that is, held for your account by a bank, broker or other nominee, you will receive instructions from the holder of record that you must follow for your shares to be voted. Stockholders that ownedhold stock in “street name” must demonstrate proof of beneficial ownership to virtually attend the meeting and mustmay be required obtain a legal proxy from their bank, broker or other nominee to vote at the meeting. A list of stockholders as of the close of business on the Record Date will be available for examinations by our stockholders during the annual meeting via the unique link that will allow you to access the meeting.

Further information about how to register for the Annual Meeting, attend the annual meetingAnnual Meeting online, vote your shares online during the meeting and submit questions during the meeting is included in the accompanying proxy statement.

Cambridge, MA

April 24, 202023, 2021

Important Notice Regarding Internet Availability of Proxy Materials: The attached proxy statement and our 20192020 annual report to stockholders, which includes our Annual Report on Form 10‑K for the fiscal year ended December 31, 2019,2020, are available for viewing, printing and downloading at www.proxydocs.com/CNST. These documents are also available to any stockholder who wishes to receive a paper copy upon written request to Constellation Pharmaceuticals, Inc. 215 First Street, Suite 200, Cambridge, MA 02142. This proxy statement and our annual report on Form 10-K for the fiscal year ended December 31, 20192020 are also available on the SEC’sSecurities and Exchange Commission’s website at http://www.sec.gov.

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CONSTELLATION PHARMACEUTICALS, INC.

PROXY STATEMENT

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215 First Street, Suite 200

Cambridge, MA 02142

(617) 714- 0555

PROXY STATEMENT

20202021 ANNUAL MEETING OF STOCKHOLDERS

To Be Held on June 4, 20202, 2021

Online at www.proxydocs.com/CNST

INFORMATION CONCERNING SOLICITATION AND VOTING

This proxy statement contains information about the Annual Meeting of Stockholders of Constellation Pharmaceuticals, Inc. (the “Annual Meeting”), or the Annual Meeting, to be held as a virtual meeting on Thursday,Wednesday, June 4, 20202, 2021 at 8:00 a.m., Eastern time.  To support the health and well-being of our stockholders, employees and directors in light of the recent novel coronavirus (“COVID-19”) outbreak, the meeting will be held Time, via the Internet at www.proxydocs.com/CNST.  There will not be a physical meeting location, and stockholders will not be able to attend the Annual Meeting in person. Further information about how to attend the Annual Meeting online is included in the accompanyingthis proxy statement.

The boardBoard of directorsDirectors of Constellation Pharmaceuticals, Inc. (our “Board of Directors” or our “Board”) is usingfurnishing you with this proxy statement in connection with soliciting your proxy to solicit proxies for usevote at the Annual Meeting.Meeting, or at any adjournment that may take place. In this proxy statement, unless expressly stated otherwise or the context otherwise requires, references to “Constellation,” “the Company,” “we,” “us,” “our” and similar terms refer to Constellation Pharmaceuticals, Inc.

All properly submitted proxies will be voted in accordance with the instructions contained in those proxies. If no instructions are specified, the shares represented by the proxies will be voted in accordance with the recommendation of our boardBoard of directorsDirectors with respect to each of the matters set forth in the accompanying Notice of Meeting. If you are a stockholder of record, you may change your vote or revoke your proxy at any time before it is exercised at the meeting by giving our Secretary written noticefollowing the instructions set forth in this proxy statement.

We have elected to that effect as our address listed below.

Instead of mailing a paper copy of our proxy materials to all of our stockholders, we are providingprovide access to our proxy materials over the Internet under the Securities and Exchange Commission’s “notice and access” rules. As a result, we are mailing to our stockholders a Notice of Internet Availability of Proxy Materials or Notice(the “Notice of Availability,Availability”) instead of a paper copy of this proxy statement and our annual report for the fiscal year ended December 31, 2019, or the 20192020 (the “2020 Annual Report.Report”). We are sending the Notice of Availability on or about April 24, 2020, and it23, 2021, which contains instructions on how to access those documents over the Internet. The Notice of Availability also contains instructions on how each of our stockholders can receive a paper copy of our proxy materials, including this proxy statement, our 20192020 Annual Report, and a form of proxy card.

Important Notice Regarding the Availability of Proxy Materials for

the Annual Meeting of Stockholders to be Held on June 4, 2020:2, 2021:

This proxy statement and our 20192020 Annual Report are

available for viewing, printing and downloading at www.proxydocs.com/CNST.

A copy of our annual report on Form 10-K for the fiscal year ended December 31, 2019,2020, as filed with the Securities and Exchange Commission or SEC,(the “SEC”), except for exhibits, will be furnished without charge to any stockholder upon written request to Constellation Pharmaceuticals, Inc. 215 First Street, Suite 200, Cambridge, MA 02142, attn. Corporate Secretary. This proxy statement and our annual report on Form 10-K for the fiscal year ended December 31, 20192020 are also available on the SEC’s website at http://www.sec.gov.

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IMPORTANT INFORMATION ABOUT TIMPORTANT INFORMATION ABHEOUT THE ANNUAL MEETING AND VOTING

Purpose of the Annual Meeting

At the Annual Meeting, our stockholders will consider and vote on the following matters:

As of the date of this proxy statement, we are not aware of any business to come before the meeting other than the first twofour items noted above.

Board of Directors Recommendation

Our boardBoard of directorsDirectors unanimously recommends that you vote:

FOR the election of the twothree nominees to serve as Class IIIII directors on our boardBoard of directors,Directors, each for a three-year term expiring at the 20232024 annual meeting of stockholders;

On an advisory basis, FOR the approval of the compensation paid to our named executive officers;

On an advisory basis, FOR the recommendation to hold future advisory votes on executive compensation every ONE YEAR; and

FOR the ratification of the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2020.2021.

Availability of Proxy Materials

The proxy materials, including this proxy statement, a proxy card and our 20192020 Annual Report are available for viewing, printing and downloading on the Internet at www.proxydocs.com/CNST. If you would like to receive a paper copy of our proxy materials, you should follow the instructions for requesting paper materials in the Notice of Availability.

Who Can Vote at the Annual Meeting?

Only stockholders of record at the close of business on the record date of April 6, 20205, 2021 (the “Record Date”) are entitled to receive notice of the Annual Meeting and to vote the shares of our common stock that they held on that date. As of April 6, 2020,the Record Date, there were 41,822,06447,914,035 shares of our common stock issued and outstanding. Each share of common stock is entitled to one vote on each matter properly brought before the Annual Meeting.

DifferenceWhat is the difference between a “stockholder of record” and a beneficial owner of shares held in “street name”?

Stockholder of Record. If your shares are registered directly in your name with our transfer agent, Computershare Trust Company, then you are considered the “stockholder of record” of those shares. In this case, your Notice of Availability has been sent to you directly by us. You may vote your shares by proxy prior to the Annual Meeting by following the instructions contained in the Notice of Availability and in the section titled “How to Vote” on page 34 of this proxy statement.

Beneficial Owner of Shares Held in Street Name. If your shares are held in a brokerage account or by a bank, trust or other nominee or custodian, then you are considered the beneficial owner of those shares, which are held in “street name.” In this case, your Notice of Availability will be sent to you by that organization. The organization holding your shares is considered the stockholder of record for purposes of voting at the Annual Meeting. As the beneficial owner, you have the right to instruct that organization as to how to vote the shares held in your account by following the instructions contained on the voting instruction card provided to you by that organization.

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Why did I receive a notice in the mail regarding the Internet availability of proxy materials instead of a full set of proxy materials?

We are pleasedhave elected to comply with the SEC rules that allow companies to distribute their proxy materials over the Internet under the “notice and access” rules of the Securities and Exchange Commission. As a result, we are sending our stockholders and beneficial owners of our common stock a copy of the Notice of Availability instead of paper copies of this proxy statement, our proxy card, and our 20192020 Annual Report. We will send the Notice of Availability on or after April 24, 2020.23, 2021. Detailed instructions on how to access these materials via the Internet may be found in the Notice of Availability. This proxy statement and our 20192020 Annual Report are available for viewing, printing and downloading on the Internet at www.proxydocs.com/CNST.CNST.  

The Notice of Availability also identifies the date and time of the virtual Annual Meeting;Meeting, instructions on how to attend the Annual Meeting online;online, the matters to be acted upon at the Annual Meeting, and our boardBoard of directors’Directors’ recommendation with regard to each matter.  In addition, the Notice of Availability will include a toll-free telephone number, an e-mail address, and a website where stockholders can request to receive, free of charge, a paper or e-mail copy of this proxy statement, our Annual Report on Form 10-K for the year ended December 31, 2020, and a form of proxy relating to the Annual Meeting, as well as information on how to access and vote the form of proxy.

Why is the Annual Meeting a virtual, online meeting?

To support the health and well-being of our stockholders, employees and directors in light of the recent COVID-19 outbreak, ourThe Annual Meeting will be held as a virtual meeting of stockholders where stockholders will participate by accessing a website usingwww.proxydocs.com/CNST and following the Internet.registration process. There will not be a physical meeting location. In light of the public health and safety concerns related to COVID-19, weWe believe that hosting a virtual meeting will facilitate stockholder attendance and participation at our Annual Meeting by enabling stockholders to safely participate from any location around the world. We have designed the virtual annual meetingAnnual Meeting to provide our stockholders with the same rights and opportunities to participate as stockholdersthey would have at an in-personin-person meeting, including the right to vote and ask questions during the meeting through the virtual meeting platform.platform.

How do I virtually attend the Annual Meeting?

The Annual Meeting will be a virtual meeting and you may not attend in person. In order to attend the meetingAnnual Meeting online, you must register in advance at www.proxydocs.com/CNST prior to the deadline of June 2, 2020May 31, 2021 at 5:00 p.m., Eastern time.time. You may attend the Annual Meeting online by following the instructions that you will receive via email once your registration is complete. The meeting will start at 8:00 a.m., Eastern timeTime, on June 4, 2020.

Online registration will begin at 5:00 p.m., Eastern time, on April 24, 2020, and you should allow ample time for the online registration.2, 2021.

Upon completing your registration, you will receive further instructions via email, including your unique link that will allow you access to the meeting and you will havesubmit questions during the ability to submit questions.meeting. Please be sure to followingfollow the instructions you will receive once your registration is complete.

You may log on to the virtual meeting startingAnnual Meeting up to one hour before it begins. If you encounter any difficulties accessing the virtual meetingAnnual Meeting during check-in or at the time of the virtual meeting,Annual Meeting, please contact technical support using the phone number that will be included in the email you will receive once you have completed your registration is complete.

registration. We will have technicians standing by and ready to assist you with any technical difficulties you may have accessingapproximately one hour ahead of the virtual meeting starting at 7:00 a.m., Eastern time, on June 4, 2020.start of the Annual Meeting.

How to Vote

If you are a stockholder of record,, you can vote your shares in one of two ways: either by proxy prior to the Annual Meeting or by voting online atduring the Annual Meeting. If you choose to vote by proxy, you may do so by telephone, via the Internet, or by mail as follows:

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Stockholders that own stockTelephone and Internet voting for stockholders of record will be available up until the start of the Annual Meeting at 8:00 a.m. Eastern Time on June 2, 2021, and mailed proxy cards must be received by 5:00 p.m., Eastern Time, on June 1, 2021 in “street name” must demonstrate proof of beneficial ownershiporder to virtually attend the meeting and must obtain a legal proxy from their bank, broker or other nominee to votebe counted at the meeting.Annual Meeting. If the Annual Meeting is adjourned or postponed, these deadlines may be extended.

Even if you plan to attend the Annual Meeting online, we urge you to vote your shares by proxy in advance of the Annual Meeting so that if you should become unable to attend the Annual Meeting, your shares will be voted as directed by you.

Telephone and Internet voting for stockholders of record will be available, and mailed proxy cards must be received in advance of the meeting in ample time in order to be counted at the Annual Meeting. If the Annual Meeting is adjourned or postponed, these deadlines may be extended.

If your shares are held in streeta “street name,” your broker nominee is required to vote the shares it holds on your behalf according to your instructions. The proxy materials, as well as voting and revocation instructions, should have been forwarded to you by the broker or nominee that holds your shares. In order to have your broker vote your shares, you will need to follow the instructions that your broker provides you.

Additionally, if your shares are held in a “street name” and you wish to virtually attend the Annual Meeting and vote your shares at the meeting, you will be required to  demonstrate proof of beneficial ownership, including entry of the unique control number during registration, and may be required to obtain a legal proxy from their bank, broker or other nominee in order to vote at the meeting. The voting deadlines and availability of telephone and Internet voting for beneficial owners of shares held in “street name” will depend on the voting processes of the broker or other organization that holds your shares. Therefore, we urge you to carefully review and follow the voting instruction card and any other materials that you receive from that organization.

Can I vote my shares by filling out and returning the Notice of Internet Availability of Proxy Materials?

No. The Notice of Availability contains instructions on how to vote via the Internet, by telephone, by requesting and returning a paper proxy card, or by voting online while virtually attending the Annual Meeting.  

How do I submit a question at the Annual Meeting?

If you wish to submit a question, you may do so in two ways. If you wish to submit a question before the Annual Meeting, you may submit ondo so during your registration at www.proxydocs.com/CNST, typeby typing your question into the “Ask a Question”“Questions for Management” field and clickclicking “Submit”. If you wish to submit a question during the Annual Meeting, you may log into, and submit a question through, the virtual meeting platform using the unique link provided to you via email following the

completion of your registration. Our virtual meeting will be governed by our Rules of Conduct which will be posted duringat www.proxydocs.com/CNST in advance of the meeting. The Rules of Conduct will address the ability of stockholders to ask questions during during the meeting, including rules on permissible topics, and rules for how questions and comments will be recognized and disclosed to meeting participants.

Quorum

A quorum of stockholders is necessary to hold a valid meeting. Our amendedIn accordance with our Amended and restated bylaws provide thatRestated Bylaws (our “Bylaws”), a quorum will exist if stockholders holdingthe holders of a majority of the shares of common stock issued and outstanding and entitled to vote atas of the meetingRecord Date are present at the meetingAnnual Meeting in person or by proxy. Shares presentof common stock that are represented virtually during the annual meetingAnnual Meeting will be considered shares of common stock represented in person at the meeting.meeting for purposes of determining whether a quorum is present. If a quorum is not present, we expect to adjourn the Annual Meeting until a quorum is obtained.

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Abstentions and broker non-votes (described below) count as present for establishing a quorum but will not be counted as votes cast.

Broker non-votes occur when your broker or other nominee submits a proxy for your shares (because the broker or other nominee has received instructions from you on one or more proposals, but not all proposals, or has not received instructions from you but is entitled to vote on a particular “discretionary” matter) but does not indicate a vote for a particular proposal because the broker or other nominee either does not have the authority to vote on that proposalNon-Votes and has not received voting instructions from you or has discretionary authority but chooses not to exercise it.

Ballot Measures Considered “Discretionary” and “Non-Discretionary”

The election of directors (Proposal No. 1) isIf you hold your shares through a matter considered non-discretionary under applicable rules. Abank, broker, or other nominee cannot(each, a “Nominee”), your Nominee, as the record holder of the shares, is required to vote withoutthose shares in accordance with your instructions.  If you do not provide voting instructions onto your Nominee (referred to as “uninstructed shares”), then your Nominee is only permitted to vote your uninstructed shares with respect to “discretionary” matters, but not with respect to “non-discretionary” matters. When there are both discretionary and non-discretionary matters to be voted on at a meeting, generally, a “broker non-vote” occurs when uninstructed shares are voted by a Nominee and therefore there maycounted for purposes of the discretionary proposals, but such uninstructed shares cannot be broker non-votes on Proposal No. 1.voted by the Nominee and thus are not counted for purposes of the non-discretionary proposal.  “Broker non-votes” refers to the votes that are represented by a Nominee at a meeting that cannot be counted for purposes of a given proposal.

The ratification ofproposal to ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 20202021 (Proposal No. 2)4) is considered a discretionary matter considered discretionary under applicable rules. A broker orrules, and all other nominee generallyproposals are considered non-discretionary. If you do not give your Nominee voting instructions, your Nominee (a) will be entitled to vote your shares on the proposal to ratify the appointment of our independent accounting firm (Proposal No. 4), and (b) will not be entitled to vote your shares on the other proposals. We urge you to provide instructions to your Nominee so that your votes may exercise discretionary authority and votebe counted on discretionary matters. If they exercise this discretionary authority, no broker non-votes are expected in connection withall of the proposals.  

Votes Required

For Proposal No. 2.

Votes Required1 (the election of three Class III directors), to Elect a Director and Ratify Appointment of Ernst & Young LLP

A nominee will be elected as a director, if thea nominee receivesmust receive a plurality of the votes cast by stockholders entitled to vote at the meeting, (Proposalmeaning the directors receiving the highest number of “for” votes will be elected.

For each of Proposal No. 1).

The ratification2 (to approve, on an advisory basis, the compensation of our named executive officers), Proposal No. 3 (to approve, on an advisory basis, one of three options for the frequency of holding future advisory votes on executive compensation), and Proposal No. 4 (to ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 2020 requires2021), the affirmative vote of the holders of a majority of the shares of common stock present or represented by proxy and voted “for” or “against”voting on such matter (Proposal No. 2)at the Annual Meeting is required for approval (meaning, the number of votes cast “for” each proposal must exceed the number of votes cast “against” each proposal).

Abstentions and broker non-votes will not be counted as votes cast or voted on any of the proposals. Accordingly, abstentions and broker non-votes will have no effect on the votingresults of the votes on eitherany of the proposals.

Method of Counting Votes

Each holder of common stock is entitled to one vote at the Annual Meeting onOn each matter to come before the Annual Meeting, including the election of directors, each holder of common stock is entitled to one vote for each share held by such stockholder as of the record date.Record Date. Votes cast online at the Annual Meeting or by proxy, whether by mail, via the Internet, or by telephone, will be tabulated by the inspector of election appointed for the Annual Meeting, who will also determine whether a quorum is present.

Revoking a Proxy; Changing Your Vote

If you are a stockholder of record, you may revoke your proxy and change your vote before the vote is taken at the meeting:Annual Meeting:

If your shares are held in “street name,” you may submit new voting instructions by contacting your bank, broker or other organization holding your shares. You may also vote online at the Annual Meeting, which will have the effect of revoking any previously submitted voting instructions, if you obtain a legal proxy from the organization that holds your shares as described in the “How to Vote” section above.

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Your virtual attending theattendance at the Annual Meeting will not automatically revoke your prior Internet vote, telephone vote, or proxy submitted by mail, as long asthe case may be, unless you do not vote online during the Annual Meeting.

Costs of Proxy Solicitation

We will bear the costs of soliciting proxies. Our directors, officers and regular employees, without additional remuneration, may solicit proxies by mail, telephone, facsimile, email, personal interviews and other means.

Voting Results

We plan to announce preliminary voting results at the Annual Meeting and will publish final results in a Current Report on Form 8-K to be filed with the SEC within four business days following the Annual Meeting.

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PROPOSAL NO. 1—ELECTIONELECTION OF TWOTHREE CLASS IIIII DIRECTORS

In accordance with the terms of our restated certificate of incorporation, our boardBoard of directorsDirectors is divided into three classes (Class I, Class II and Class III), with members of each class serving staggered three-year terms. The members of the classes are divided as follows:

Upon the expiration of the term of a class of directors, directors in that class will be eligible to be elected for a new three-year term at the annual meeting of stockholders in the year in which their term expires.

Our restated certificate of incorporation provides that the authorized number of directors may be changed only by resolution of our boardBoard of directors.Directors. Our restated certificate of incorporation also provides that our directors may be removed only for cause and only by the affirmative vote of the holders of at least 75% of the votes that all our stockholders would be entitled to cast in an annual election of directors, and that any vacancy on our boardBoard of directors,Directors, including a vacancy resulting from an enlargement of our boardBoard of directors,Directors, may be filled only by vote of a majority of our directors then in office.

Our boardBoard of directorsDirectors currently consists of eightseven members. Our boardUpon the recommendation of directorsthe nominating and corporate governance committee of our Board of Directors (the “Nominating and Corporate Governance Committee”), our Board of Directors has nominated James E. AudiaScott N. Braunstein, Mark A. Goldsmith, and Steven L. HoerterJigar Raythatha for election as Class IIIII directors at the Annual Meeting. Dr. AudiaMeeting, to serve until the 2024 annual meeting of stockholders, or until their respective successors are duly elected and qualified. Drs. Braunstein and Goldsmith and Mr. HoerterRaythatha are bothall presently directors and haveeach has indicated a willingnesshe is willing to continue to serve as directors,a director, if elected. If any of the nominees become unableIf either Dr. Audia or Mr. Hoerter becomes unable or unwilling to serve, however, the proxies may be voted for substitute nominees selected by our boardBoard of directors. Dr. Tepper has decidedDirectors.

While we do not to stand for re-election

We have noa formal policy regarding board diversity, but our Corporate Governance Guidelines provide that the value of diversity should be considered in evaluating nominees to recommend for election to our Board of Directors, and that the backgroundbackgrounds and qualifications of the members of our board of directors, considered as a group, should provide a significant breadth of experience, knowledge, and ability to assist our boardBoard of directorsDirectors in fulfilling its responsibilities. Our priority in selection of boardselecting Board members is identification ofidentifying members who will further the interests of our stockholders through their established records of professional accomplishment, the ability to contribute positively to the collaborative culture among our boardBoard members, knowledge of our business, understanding of the competitive landscape in which we operate, and adherence to high ethical standards. Certain individual qualifications and skills of our directors that contribute to our boardBoard of directors’Directors’ effectiveness as a whole are described in the following paragraphs:

Nominees for Election as Class IIIII Directors

Biographical information as of April 1, 2020,2021, including principal occupation and business experience during the last five years, for our nominees for election as Class IIIII directors at our Annual Meeting is set forth below.

James E. Audia, Ph.D.Scott N. Braunstein, M.D., age 64,57, has served as a member of our boardBoard of directorsDirectors since July 2017.February 2019.  Dr. Audia is the president and sole proprietor of Audia Consulting, LLC, a scientific consulting firm which he founded in September 2019.  Since November 2019, heBraunstein has also served as an entrepreneur in residence for Third Rock Ventures, a venture capital firm. Since November 2019 he has also been senior advisor and headthe Chief Executive Officer of chemistry for Karuna Therapeutics,Marinus Pharmaceuticals, a publicly traded biopharmaceutical company. Dr Audia has been a member of the Alzheimer’s Associationcompany, since January 2020.  Between August 2017 and October 2019,2019.  Dr. AudiaBraunstein also serves as an Operating Partner at Aisling Capital since September 2015. From July 2015 to March 2018, Dr. Braunstein served as Executive DirectorChief Operating Officer, SVP of the Chicago Biomedical Consortium, or CBC,Corporate Strategy and Chief Strategy Officer at Pacira Pharmaceuticals, Inc., a collaborative effort of Northwestern University, The University of Chicago and The University of Illinois-Chicago, focused on enhancing biomedical innovation. Prior to joining the CBC,specialty pharmaceutical company. Dr. Audia served as our chief scientific officer from January 2011 to July 2017. Prior to joining us as chief scientific officer, Dr. Audia served in a number of roles at Eli Lilly & Company, a global healthcare company, from 1987 until December 2010. From January 2011 to December 2017,

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Dr. AudiaBraunstein served as a scientific advisorhealthcare portfolio manager at J.P. Morgan Asset Management, an investment firm from 2002 to Sage Therapeutics, Inc.,2014, and Everpoint Asset Management from 2014 to 2015.  Dr. Braunstein was a public biopharmaceutical company.healthcare analyst and managing director at J.P. Morgan Asset Management and portfolio manager for the J.P. Morgan Global Healthcare fund. Dr. Audia alsoBraunstein currently serves as a scientific advisor and a member ofon the board of directors of Ribonthe following public companies: Marinus Pharmaceuticals, Inc.  and Trevena, Inc., and Dr. Braunstein previously served on the

board of directors of the following public companies: Esperion Therapeutics, Inc., a private biotechnology company. until April 2020, Ziopharm Oncology, Inc. until November 2020, and Protara Therapeutics, Inc. (formerly known as ArTara Therapeutics, Inc.) until July 2020. He received a B.S.earned his Bachelor of Applied Science from Cornell University and Ph.D. in organic chemistryhis M.D. from the UniversityAlbert Einstein College of South Carolina and completed postdoctoral training at Yale University.Medicine. We believe that Dr. Audia’sBraunstein’s extensive experience in the biopharmaceutical industryserving on public company boards of directors, including biotechnology company boards, and his prior experience as our chief scientific officerstrong financial and business acumen qualify him to serve as a member of our boardBoard of directors.Directors.

Steven L. HoerterMark A. Goldsmith, M.D., Ph.D., age 49, 59, has served as a member of our Board of Directors since July 2009. Dr. Goldsmith has been the President and Chief Executive Officer and a director of Revolution Medicines, Inc., a publicly traded drug discovery and development company, since November 2014. Dr. Goldsmith was previously a partner with Third Rock Ventures, L.P. (“Third Rock”), a venture capital firm, from March 2012 until 2015 and a venture partner with Third Rock from 2015 until March 2018. Dr. Goldsmith previously served as our President and Chief Executive Officer from June 2009 to March 2012 and as our Interim Executive Chairman from June 2016 to March 2017. Dr. Goldsmith served as President and Chief Executive Officer of Global Blood Therapeutics, a biotechnology company, from May 2012 to June 2014, and on its board of directors sincefrom May 2012 to September 2018.  Mr. Hoerter is currently the chief executive officer2014. Dr. Goldsmith also served as President and Chief Executive Officer of Deciphera Pharmaceuticals,Nurix, Inc. (“Deciphera”), a clinical stage public biopharmaceutical company, a position he has held since March 18, 2019.  Prior to joining Deciphera, Mr. Hoerter served as the chief commercial officer of Agios Pharmaceuticals, a biopharmaceuticaldrug discovery company, from February 2016May 2012 to March 2019. He has more than 20 yearsOctober 2014. Before entering the private sector, Dr. Goldsmith led a medical research laboratory at the Gladstone Institute of globalVirology and Immunology, practiced medicine on the faculty of the School of Medicine of the University of California, San Francisco and the San Francisco General Hospital, and was a consultant to leading pharmaceutical and biotechnology experience.  Mr. Hoerter served,companies. Dr. Goldsmith holds an A.B. from August 2011 to February 2016, as executive vice president and chief commercial officer at Clovis Oncology, Inc., a biopharmaceutical company. Before joining Clovis in August 2011, he was general manager and management center head at Roche Group for the Sub-Saharan Africa and Indian Ocean Region. From 2005 to 2010, Mr. Hoerter held a variety of positions at Genentech, Inc., including serving on the senior leadership team for Genentech’s bio-oncology business as senior director, pipeline development and commercial operations. Mr. Hoerter serves on the board of directors of Deciphera and served on the board of directors of Ignyta Pharma, a public pharmaceutical company, from December 2016 to February 2018.  Prior to that, Mr. Hoerter held commercial roles at Chiron Corporation and Eli Lilly and Company in the United States, Europe and Africa. Mr. Hoerter received his B.A. from Bucknell University, M.B.A. from TilburgPrinceton University and M.S.a M.D. and Ph.D. in managementmicrobiology and immunology from Purdue University.the University of California, San Francisco. We believe that Mr. Hoerter’s globalDr. Goldsmith’s investment and operations experience in the biopharmaceuticallife sciences industry and his experience serving as a member of a public company board of directors qualify him to serve as a member of our boardBoard of directors.Directors.

Jigar Raythatha, age 44, has served as our President and Chief Executive Officer and as a member of our Board of Directors since March 2017. Mr. Raythatha previously served as Chief Business Officer of Jounce Therapeutics, Inc., a biotechnology company, from December 2012 to February 2017, where he helped build the company from its inception to a publicly traded research and development organization. Previously, he served as our Head of Corporate Development from March 2009 to February 2013, where he led business development, strategy and program and alliance management functions. Prior to serving as our Head of Corporate Development, Mr. Raythatha joined Red Abbey Venture Partners, LLC in 2005 and served as a Kauffman Fellow from 2005 to 2007, principal from 2007 to 2009 and venture partner in 2009. Prior to Red Abbey Venture Partners, Mr. Raythatha worked at Biogen Inc. from 1999 to 2003 in a variety of business development, commercial, and program management roles. He earned an M.B.A. from Columbia University and a B.A. in biochemistry and economics from Rutgers University. We believe that Mr. Raythatha’s extensive leadership experience in the life sciences industry and his extensive knowledge of our company based on his prior role as our Head of Corporate Development and in his current role as our Chief Executive Officer qualify him to serve as a member of our Board of Directors.

The boardBoard of directorsDirectors unanimously recommends voting “FOR” the election of James E. Audia,Scott N. Braunstein, M.D., Mark A. Goldsmith, M.D., Ph.D., and Steven L. HoerterJigar Raythatha as Class IIIII directors for a three-year term ending at the annual meeting of stockholders to be held in 20232024.

Class II Director Not Standing for Re-Election

Robert Tepper, M.D., age 64, has served as a member of our board of directors since April 2008. Dr. Tepper is a general partner of Third Rock, which he co-founded in March 2007 and focuses on the formation, development and scientific strategy of Third Rock’s portfolio companies, as well as actively identifying and evaluating new investments. Dr. Tepper served as our chief scientific officer from April 2008 to October 2009. Prior to joining Third Rock, Dr. Tepper served as President of Research and Development at Millennium Pharmaceuticals, Inc., or Millennium. Prior to joining Millennium in 1994, he served as principal investigator in the laboratory of tumor biology at the Massachusetts General Hospital Cancer Center. Dr. Tepper is also a founder and former member of the scientific advisory board of Cell Genesys/Abgenix Inc. Dr. Tepper serves as an adjunct faculty member at Harvard Medical School and Massachusetts General Hospital and is an advisory board member of several healthcare institutions, including the Partners HealthCare Center for Personalized Genetic Medicine, Harvard Medical School and Tufts Medical School. Dr. Tepper serves as a board member of Jounce Therapeutics, Inc., Neon Therapeutics, Inc. and Allena Pharmaceuticals, Inc., each a biopharmaceutical company, and was previously a board member of bluebird bio, Inc. from 2010 to 2015, Kala Pharmaceuticals, Inc. from 2009 to 2018,  and Cerulean Pharmaceuticals Inc. from 2006 to 2015. Dr. Tepper is currently a board member of several private life sciences companies. Dr. Tepper holds an A.B. in biochemistry from Princeton University and an M.D. from Harvard Medical School. We believe that Dr. Tepper’s experience in the venture capital industry, particularly with biotechnology and pharmaceutical companies, combined with his experience building and operating research and development operations, on the boards of public and private life sciences companies and as faculty and advisory board member of several healthcare institutions, qualified him to serve as a member of our board of directors, and we thank him for his service.

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Directors Continuing in Office

Biographical information as of April 1, 2020,2021, including principal occupation and business experience during the last five years, for our directors continuing in office after the Annual Meeting is set forth below.

Class I Directors

Richard S. Levy, M.M.DD.., age 6263 has served as a member of our boardBoard of directorsDirectors since April 2020.  From December 2016 to May 2019, Dr. Levy served as a senior advisorSenior Advisor at Baker Brothers Advisors, a health care investment company. From January 2009 to AprilMay 2016, Dr. Levy served as Executive Vice President and Chief Drug Development Officer of Incyte Corporation, a pharmaceutical company, where he previously served as Senior Vice President of Drug Development from August 2003 to January 2009. Prior to joining Incyte, Dr. Levy served as Vice President, Biologic Therapies, at Celgene Corporation, a biopharmaceutical company, from 2002 to 2003.  Dr. Levy currently serves on the boards of the following public companies: Madrigal Pharmaceuticals, Inc., Kodiak Sciences Inc., Kiniksa Pharmaceuticals, Ltd., and Protara Therapeutics, Inc. (formerly known as ArTara Therapeutics.Therapeutics, Inc.). Dr. Levy received his M.D. from the University of Pennsylvania School of Medicine and completed his training in Internal Medicine at the Hospital of the University of Pennsylvania and a fellowship in Gastroenterology and Hepatology at UCLA.  We believe that Dr. Levy’s nearly 30 years of experience in the pharmaceutical and biotechnology sectors as well as his experience as a medical professional, biopharmaceutical executive, and board member of other public companies qualifies him to serve as a member of our boardBoard of directors.Directors.

Elizabeth Trehu,G. Tréhu, M.D., age 59,60, has served as a member of our boardBoard of directorsDirectors since September 2018.  Dr. TrehuTréhu is currently the chief medical officerChief Medical Officer of Jounce Therapeutics, Inc., a publicly traded clinical stage immunotherapy company, where she has served since November 2015. Prior to joining Jounce, Dr. TrehuTréhu served as the chief medical officerChief Medical Officer of Promedior, Inc., a biotechnology company, from 2012 to November 2015. Previously, Dr. TrehuTréhu served as vice president, product developmentVice President, Product Development and medical affairsMedical Affairs for Infinity Pharmaceuticals, Inc. from 2010 to 2012. Earlier in her career, Dr. TrehuTréhu served in a variety of roles for Genzyme Corporation, including as the vice presidentVice President and general manager, hematologyGeneral Manager, Hematology from 2009 to 2010, vice presidentVice President and general managerGeneral Manager of Clolar from 2008 to 2009 and vice president, global medical affairsVice President, Global Medical Affairs of Genzyme Oncology from 2006 to 2008. From 2002 to 2006, Dr. TrehuTréhu served in a variety of positions at Millennium Pharmaceuticals, Inc., including as vice presidentVice President of oncology global medical affairsOncology Global Medical Affairs in 2006. Dr. TrehuTréhu holds an M.D. from the New York University School of Medicine and an A.B. in English from Princeton University. We believe that Dr. Trehu’sTréhu’s medical expertise in the cancer field as well as her experience as a senior executive of public biopharmaceutical companies qualify her to serve as a member of our boardBoard of directors.Directors.

Class IIIII Directors

Scott Braunstein, M.D.James E. Audia, Ph.D., age 56,65, has served as a member of our boardBoard of directorsDirectors since FebruaryJuly 2017. Dr. Audia is the President and Sole Proprietor of Audia Consulting, LLC, a scientific consulting firm which he founded in September 2019.  Dr. Braunstein has served as the chief executive officer of Marinus Pharmaceuticals, a publicly traded biopharmaceutical company, since August 2019.  Dr. BraunsteinSince November 2019, he has also served as an operating partner at Aisling Capitalentrepreneur in residence for Third Rock Ventures, a venture capital firm. Since November 2019 he has also been Senior Advisor and Head of Chemistry for Karuna Therapeutics, Inc., a publicly traded biopharmaceutical company. Dr Audia has been on the scientific advisory board of the Alzheimer’s Association since September 2015. From July 2015 to March 2018,January 2020.  Between August 2017 and October 2019, Dr. BraunsteinAudia served as chief operating officer, SVPExecutive Director of corporate strategy and chief strategy officer at Pacira Pharmaceuticals, Inc.the Chicago Biomedical Consortium (“CBC”), a specialty pharmaceutical company.collaborative effort of Northwestern University, The University of Chicago and The University of Illinois-Chicago, focused on enhancing biomedical innovation. Prior to joining the CBC, Dr. BraunsteinAudia served as our Chief Scientific Officer from January 2011 to July 2017. Prior to joining us as Chief Scientific Officer, Dr. Audia served in a number of roles at Eli Lilly & Company, a global healthcare company, from 1987 until December 2010. From January 2011 to December 2017, Dr. Audia served as a healthcare portfolio manager at J.P. Morgan Asset Management, an investment firm from 2002scientific advisor to 2014, and Everpoint Asset Management from 2014 to 2015.  Dr. Braunstein was a healthcare analyst and managing director at J.P. Morgan Asset Management and portfolio manager for the J P Morgan Global Healthcare fund. Dr. Braunstein serves as a member of the following public company boards of directors: ArTaraSage Therapeutics, Inc., Esperion Therapeutics, Inc., Marinus Pharmaceuticals, Inc., Ziopharm Oncology, Inc.a public biopharmaceutical company. He received a B.S. and Trevena, Inc. Dr. Braunstein also serves on the board of directors of private biotechnology companies. He earned his Bachelor of Applied Science from Cornell University and his MDPh.D. in organic chemistry from the Albert Einstein CollegeUniversity of Medicine. South Carolina and completed postdoctoral training at Yale University. We believe that Dr. Braunstein’sAudia’s extensive experience serving on public company boards of directors, including biotechnology company boards,in the biopharmaceutical industry and his strong financial and business acumenprior experience as our Chief Scientific Officer qualify him to serve as a member of our boardBoard of directors.Directors.

Mark A. Goldsmith, M.D.Steven L. Hoerter, Ph.D., age 58,50, has served as a member of our boardBoard of directorsDirectors since July 2009. Dr. GoldsmithSeptember 2018.  Mr. Hoerter is currently the President and Chief Executive Officer of Deciphera Pharmaceuticals, Inc. (“Deciphera”), a clinical stage public biopharmaceutical company, a position he has beenheld since March 18, 2019.  Prior to joining Deciphera, Mr. Hoerter served as the presidentChief Commercial Officer of Agios Pharmaceuticals, a public biopharmaceutical company, from February 2016 to

March 2019. He has more than 20 years of global pharmaceutical and chief executive officerbiotechnology experience.  Mr. Hoerter served, from August 2011 to February 2016, as Executive Vice President and a director of Revolution Medicines,Chief Commercial Officer at Clovis Oncology, Inc., a publicly traded drug discoverypublic biopharmaceutical company. Before joining Clovis in August 2011, he was General Manager and development company, since November 2014. Dr. Goldsmith was previouslyManagement Center Head at Roche Group for the Sub-Saharan Africa and Indian Ocean Region. From 2005 to 2010, Mr. Hoerter held a partner with Third Rock Ventures, L.P., or Third Rock, a venture capital firm, from March 2012 until 2015 and a venture partner with

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Third Rock from 2015 until March 2018. Dr. Goldsmith previously served as our president and chief executive officer from June 2009 to March 2012 and as our interim executive chairman from June 2016 to March 2017. Dr. Goldsmith served as president and chief executive officer of Global Blood Therapeutics, a biotechnology company, from May 2012 to June 2014, and on its board of directors from May 2012 to September 2014. Dr. Goldsmith also served as president and chief executive officer of Nurix,positions at Genentech, Inc., a drug discovery company, from May 2012 to October 2014. Dr. Goldsmith alsoincluding serving on the senior leadership team for Genentech’s bio-oncology business as Senior Director, Pipeline Development and Commercial Operations. Mr. Hoerter serves on the board of directors of various private biotechnology companies. Before entering the private sector, Dr. Goldsmith led a medical research laboratory at the Gladstone Institute of VirologyDeciphera and Immunology, practiced medicineserved on the facultyboard of directors of Ignyta Pharma, a public pharmaceutical company, from December 2016 to February 2018.  Prior to that, Mr. Hoerter held commercial roles at Chiron Corporation and Eli Lilly and Company in the School of Medicine of theUnited States, Europe and Africa. Mr. Hoerter received his B.A. from Bucknell University, of California, San Francisco and the San Francisco General Hospital, and was a consultant to leading pharmaceutical and biotechnology companies. Dr. Goldsmith holds an A.B.M.B.A. from PrincetonTilburg University and a M.D. and Ph.D.M.S. in microbiology and immunologymanagement from the University of California, San Francisco.Purdue University. We believe that Dr. Goldsmith’s investment and operationsMr. Hoerter’s global experience in the life sciencesbiopharmaceutical industry and his experience serving as a member of a public company board of directors qualify him to serve as a member of our boardBoard of directors.

Jigar Raythatha, age 43, has served as our president and chief executive officer and as a member of our board of directors since March 2017. Mr. Raythatha previously served as chief business officer of Jounce Therapeutics, Inc., a biotechnology company, from December 2012 to February 2017, where he helped build the company from its inception to a publicly traded research and development organization. Previously, he served as our head of corporate development from March 2009 to February 2013, where he led business development, strategy and program and alliance management functions. Prior to serving as our head of corporate development, Mr. Raythatha joined Red Abbey Venture Partners, LLC in 2005 and served as a Kauffman fellow from 2005 to 2007, principal from 2007 to 2009 and venture partner in 2009. Prior to Red Abbey Venture Partners, Mr. Raythatha worked at Biogen Inc. from 1999 to 2003 in a variety of business development, commercial, and program management roles. He earned an M.B.A. from Columbia University and a B.A. in biochemistry and economics from Rutgers University. We believe that Mr. Raythatha’s extensive leadership experience in the life sciences industry and his extensive knowledge of our company based on his prior role as our head of corporate development and in his current role as our chief executive officer qualify him to serve as a member of our board of directors.Directors.

Executive Officers Who Are Not Directors

Biographical information as of April 1, 20202021 for our executive officers who are not directors is listed below.

Emma Reeve, age 59,60, has served as our senior vice presidentSenior Vice President and chief financial officerChief Financial Officer since October 2017 and as our treasurerTreasurer since December 2017. Prior to joining us, Ms. Reeve served as corporate controllerCorporate Controller of PAREXEL International, a life sciences consulting firmbiopharmaceutical services company and contract research organization, from September 2014 to October 2017 and as interim chief financial officerInterim Chief Financial Officer and corporate controllerCorporate Controller of PAREXEL from July 2016 to May 2017, where she was responsible for all aspects of financial reporting and accounting, investor relations, financial planning and analysis. Previously, Ms. Reeve served as headHead of financeFinance and administrationAdministration at Novartis Pharma Schweiz, a pharmaceutical company, from May 2012 to August 2014 and as vice president, global head business planningVice President, Global Head Business Planning and analysisAnalysis for Novartis Vaccines and Diagnostics, a division of Novartis, from January 2008 to April 2012. She served as chief financial officerChief Financial Officer of Inotek Pharmaceuticals Inc., a development-stage biotechnology company, from 2006 to 2007. Ms. Reeve was senior directorSenior Director of research operationsResearch Operations at Merck Research Laboratories from 2004 to 2006. Prior to that she served as chief financial officerChief Financial Officer of Aton Pharma, Inc., a development-stage biotechnology company, from 2002 to 2004. Ms. Reeve was at Bristol-Myers Squibb Company, a global biopharmaceuticals company, from 1994 to 2002. Ms. Reeve holds a B.Sc. in computer science from Imperial College, University of London and is an associate of the Institute of Chartered Accountants in England & Wales.

Adrian Senderowicz,Jeffrey Humphrey, M.D., age 56,59, has served as our senior vice president and chief medical officerChief Medical Officer since July 2017, prior to which he provided consulting services to us from May 2017 until the commencement of his employment with us.June 2020. Prior to joining us, Dr. SenderowiczHumphrey served as chief medical officerin various positions at Cerulean Pharma, Inc., an oncology-focused biotechnology company now known as Daré Bioscience, Inc., from September 2015 to June 2017, where he helped secure Fast Track designation for the company’s lead clinical development program in two indications. Previously,

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Dr. Senderowicz was chief medical officer and senior vice president, clinical development and regulatory affairs at Ignyta, Inc.Kyowa Kirin Co. Ltd. (“Kyowa Kirin), a pharmaceutical and biotechnology company, from April 2012 to June 2020. At Kyowa Kirin, he served as Chief Development Officer from August 20142019 to April 2015. Prior to that he was vice president, global oncology regulatory head at Sanofi S.A., a global pharmaceutical company,June 2020, as President and Chief Medical Officer of Kyowa Kirin Pharmaceutical Development, Inc. from JulyApril 2013 to August 20142019, and served as chief medical officer at Tokai Pharmaceuticals,Senior Vice President, Drug Development of Kyowa Hakko Kirin Pharma, Inc., a biopharmaceutical company now known as Novus Therapeutics, Inc., from AugustApril 2012 to March 2013. He previously served in senior management positions for early and late drug development and medical affairs at Pfizer, Bayer, and Bristol Myers Squibb. Dr. Senderowicz wasHumphrey holds a medical directorA.B. from Harvard University and senior medical director at AstraZeneca PLC, a global biopharmaceutical company,an M.D. from 2008 to 2012. He began his career as an investigator at the National Cancer Institute before joining the Center for Drug Evaluation and Research at the FDA. Since September 2015, Dr. Senderowicz has served on the board of directors of Puma Biotechnology, a public biotechnology company. Dr. Senderowicz is a board-certified medical oncologist. Dr. Senderowicz completed his Internal Medicine residency training at the IcahnCase Western Reserve University School of Medicine at Mount Sinai and a Clinical Oncology Fellowship at the National Cancer Institute. He holds an M.D. degree from the School of Medicine at the Universidad de Buenos Aires in Argentina.Medicine.

Patrick Trojer, Ph.D., age 47,48, has served as our chief scientific officerChief Scientific Officer since November 2018.  Prior to that, Dr. Trojer served as our senior vice president,Senior Vice President, EZH2 franchise and headHead of translational sciencesTranslational Sciences since June 2017. Dr. Trojer joined us as a founding scientist in 2008. Dr. Trojer has served in various positions at our company, including as vice president, headVice President, Head of researchResearch from October 2015 to June 2017, executive director, headExecutive Director, Head of biologyBiology from October 2014 to October 2015, senior director, headSenior Director, Head of biologyBiology from March 2012 to October 2014, director, headDirector, Head of biologyBiology from 2010 to March 2012, senior scientistSenior Scientist from 2009 to 2010 and scientistScientist from 2008 to 2009. Dr. Trojer completed his postdoctoral studies at NYU Medical School, prior to which he received a Ph.D. in protein biochemistry and molecular biology and an M.S. in microbiology from the Leopold Franzens University in Innsbruck, Austria.

Karen Valentine, age 48,49, has served as our Chief Legal Officer and General Counsel since July 2018. Prior to joining us, Ms. Valentine served as the chief legal officerChief Legal Officer and general counselGeneral Counsel of Agenus Inc., a publicly traded immune-oncology company from September 2015 to July 2018 and served as vice presidentVice President and general counselGeneral Counsel of Agenus Inc. from January 2008 to September 2015. Prior to joining Agenus Inc. in 2004, Ms. Valentine was an associate in the biotechnology practice of Palmer & Dodge LLP (now Locke Lorde)Lorde LLP). Ms. Valentine is currently the president and a member of the board of directors of the Northeast Chapter of the Association of Corporate Counsel. Ms. Valentine holds a B.S. in neuroscience from Colgate University and received her J.D. from Boston University School of Law.

The principal occupation and employment during the past five years of each of our directors and executive officers was carried on, in each caseexcept as specifically identified above, with a corporation or organization that is not a parent, subsidiary or other affiliate of us. There is no arrangement or understanding between any of our directors or executive officers and any other person or personspersons pursuant to which he or she was or is to be selected as a director or executive officer.

There are no material legal proceedings to which any of our directors or executive officers is a party adverse to us or any of our subsidiaries or in which any such person has a material interest adverse to us or any of our subsidiaries.

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PROPOSAL 2—RATIFICATION OF THE APPOINTMENT OF ERNST & YOUNG LLP

AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR THE FISCAL YEAR ENDING

DECEMBER 31, 2020

Our stockholders are being asked to ratify the appointment by the audit committee of the board of directors of Ernst & Young LLP as our independent registered public accounting firm. Ernst & Young LLP has served as our independent registered public accounting firm since 2008.

The audit committee is solely responsible for selecting our independent registered public accounting firm for the fiscal year ending December 31, 2020. Stockholder approval is not required to appoint Ernst & Young LLP as our independent registered public accounting firm. However, the board of directors believes that submitting the appointment of Ernst & Young LLP to the stockholders for ratification is good corporate governance. If the stockholders do not ratify this appointment, the audit committee will reconsider whether to retain Ernst & Young LLP. If the selection of Ernst & Young LLP is ratified, the audit committee, in its discretion, may direct the appointment of a different independent registered public accounting firm at any time it decides that such a change would be in the best interest of our company and our stockholders.

A representative of Ernst & Young LLP is expected to be present at the Annual Meeting and will have an opportunity to make a statement if he or she desires to do so and is expected to be available to respond to appropriate questions from our stockholders.

We incurred the following fees from Ernst & Young LLP for the audit of the consolidated financial statements and for other services provided during the years ended December 31, 2019 and 2018.

Audit Committee Pre-Approval Policy and Procedures

Our audit committee has adopted policies and procedures relating to the approval of all audit and non-audit services that are to be performed by our independent registered public accounting firm. This policy provides that we will not engage our independent registered public accounting firm to render audit or non-audit services unless the service is specifically approved in advance by our audit committee or the engagement is entered into pursuant to the pre-approval procedure described below.

From time to time, our audit committee may pre-approve specified types of services that are expected to be provided to us by our independent registered public accounting firm during the next 12 months. Any such pre-approval is detailed as to the particular service or type of services to be provided and is also generally subject to a maximum dollar amount.

During our 2019 and 2018 fiscal years, no services were provided to us by Ernst & Young LLP other than in accordance with the pre-approval policies and procedures described above.

The board of directors recommends voting “FOR” Proposal No. 2 to ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for the fiscal year ending December 31, 2020.

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CORPORATE GOVERNANCE

Director Nomination Process

Our nominatingNominating and corporate governance committeeCorporate Governance Committee is responsible for identifying individuals qualified to serve as directors, consistent with criteria approved by our board, and recommending the persons to be nominated for election as directors, except where we are legally required by contract, law or otherwise to provide third parties with the right to nominate director candidates.

The process followed by our nominatingNominating and corporate governance committeeCorporate Governance Committee to identify and evaluate director candidates includes requests to board members and others for recommendations, meetings from time to time to evaluate biographical information and background material relating to potential candidates and interviews of selected candidates by members of the committee and our board.Board of Directors. While there are no specific minimum qualifications for a committee-recommended nominee to our boardBoard of directors,Directors, the qualifications, qualities and skills that our nominatingNominating and corporate governance committeeCorporate Governance Committee believes must be met by a committee-recommended nominee for a position on our boardBoard of directorsDirectors are as follows:

The nominatingNominating and corporate governance committeeCorporate Governance Committee may use a third-party search firm in those situations where particular qualifications are required or where existing contacts are not sufficient to identify an appropriate candidate.

Stockholders may recommend individuals to the nominatingNominating and corporate governance committeeCorporate Governance Committee for consideration as potential director candidates. Any such proposals should be submitted to our corporate secretarySecretary at our principal executive offices and should include (i) appropriate biographical and background material to allow the nominatingNominating and corporate governance committeeCorporate Governance Committee to properly evaluate the potential director candidate, and (ii) the number of shares of our stock beneficially owned by the stockholder proposing the candidate. The specific requirements for the information that is required to be provided for such recommendations to be considered are specified in our amended and restated bylawsBylaws and must be received by us no later than the date referenced below under the heading “Stockholder Proposals for our 20212022 Annual Meeting.”

Assuming that biographical and background material has been provided on a timely basis, any recommendations received from stockholders will be evaluated in the same manner as potential nominees proposed by the nominatingNominating and corporate governance committee.Corporate Governance Committee. If our boardBoard of directorsDirectors decides to nominate a stockholder-recommended candidate and recommends his or her election, then his or herthe candidate’s name will be included on our proxy card for the next annual meeting.

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Director Independence

Applicable rules of the Nasdaq Stock Market or Nasdaq,(“Nasdaq”) require a majority of a listed company’s board of directors to be comprised of independent directors within one year of listing. In addition, Nasdaq rules require that, subject to specified exceptions, each member of a listed company’s audit, compensation, and nominating and corporate governance committees be independent under the Securities Exchange Act of 1934, as amended or the Exchange Act.(the “Exchange Act”). Audit committee members must also satisfy the independence criteria set forth in Rule 10A-3 under the Exchange Act, and compensation committee members must also satisfy the independence criteria set forth in Rule 10C-1 under the Exchange Act. Under applicable Nasdaq rules, a director will only qualify as an “independent director,” if in the opinion of the listed company’s board of directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In order for a member of the audit committee of a listed company to be considered independent for purposes of Rule 10A-3 under the Exchange Act, athe member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee or as a member of the board of directors or any other board committee, accept, directly or indirectly, any consulting,consulting, advisory, or other compensatory fee from the listed company or any of its subsidiaries, or otherwise be an affiliated person of the listed company or any of its subsidiaries. In order for a member of the compensation committee of a listed company to be considered independent for purposes of Rule 10C-1 under the Exchange Act, the board must consider for each member of a compensation committee of a listed company, all factors specifically relevant to determining whether a director has a relationship to such company which is material to that director’s ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to: (1) the source of compensation of the director, including any consulting advisory or other compensatory fee paid by such company to the director; and (2) whether the director is affiliated with the company or any of its subsidiaries or affiliates.

In March 2020,2021, our boardBoard of directorsDirectors undertook a review of the composition of our boardBoard of directors andDirectors, each of its committees, and the independence of each director. Based upon information requested from and provided by each director concerning his or her background, employment, and affiliations, including family relationships, our boardBoard of directorsDirectors has determined that each of our directors, with the exception of Mr. Raythatha, and Dr. Audia, is an “independent director” as defined under applicable Nasdaq rules, including, in the caserules.  The Board of allDirectors has additionally determined that each of the members of ourthe audit committee of our Board of Directors (the “Audit Committee”) meet the independence criteria set forth in Rule 10A-3 under the Exchange Act, and in the caseeach of all the members of ourthe compensation committee of our Board of Directors (the “Compensation Committee”) meet the independence criteria set forth in Rule 10C-1 under the Exchange Act. In making such determination, our boardBoard of directorsDirectors considered the relationships that each such non-employee director has with our companyCompany and all other facts and circumstances that our boardBoard of directorsDirectors deemed relevant in determining his or hersuch director’s independence, including the beneficial ownership of our capital stock by each non-employee director. Mr. Raythatha is not an independent director under these rules because he is our presidentPresident and chief executive officer, and Dr. Audia is not an independent director under these rules because he served as our chief scientific officer until July 2017.Chief Executive Officer.

There are no family relationships among any of our directors or executive officers.

Committees of the Board of Directors

Our boardBoard of directorsDirectors has established an audit committee,Audit Committee, a compensation committee,Compensation Committee, a nominatingNominating and corporate governance committeeCorporate Governance Committee, and a researchResearch and development committee.Development Committee (the “R&D Committee”). Each of the audit committee, compensation committee, nominatingAudit Committee, Compensation Committee, Nominating and corporate governance committeeCorporate Governance Committee, and research and development committeeR&D Committee operates under a charter, and each such committee reviews its respective charter at least annually. A current list of the members of each committee, and a current copy of the charter for each of the audit committee, compensation committeeAudit Committee, Compensation Committee, and the nominatingNominating and corporate governance committee isCorporate Governance Committee are posted on the “Corporate Governance” sectionpage of the “Investors & Media” section of our website, which is located at www.constellationpharma.com. The Board also appoints from time to timetime-to-time ad hoc committees to address specific matters.

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Audit committeeCommittee

During 2019,2020, the members of our audit committeethe Audit Committee consisted of Scott N. Braunstein, Anthony Evnin, Mark A. Goldsmith, and Peter Svennilson. Anthony EvninSteven L. Hoerter. Scott N. Braunstein, who serves as chair of the Audit Committee, and Mark A. Goldsmith were

members of the audit committeeAudit Committee for the entirety of 2019. Scott Braunstein joined the audit committee in March 2019, and serves as the chair of the audit committee.  Peter Svennilson left the audit committee effective as of the end of his term as a director at the 2019 annual meeting.2020.  Steven L. Hoerter joined the audit committeeAudit Committee in late January 2020, replacing Anthony Evnin who stepped down as a member and chair of the audit committeeAudit Committee at that time.  Our audit committeeThe Audit Committee met five (5)six (6) times during 2019. Our audit committee’s2020.  The Audit Committee’s responsibilities include:

All audit and non-audit services, other than de minimis non-audit services, to be provided to us by our independent registered public accounting firm must be approved in advance by our audit committee.the Audit Committee.

Our boardBoard of directorsDirectors has determined that Scott N. Braunstein and Mark A. Goldsmith areis an “audit committee financial experts”expert” as defined in applicable SEC rules, and that each of the members of our audit committeeAudit Committee possesses the financial sophistication required for audit committee members under Nasdaq rules. We believe that the composition of our audit committeeAudit Committee meets the requirements for independence under current Nasdaq and SEC rules and regulations.

Compensation committeeCommittee

During 2019,2020, the members of our compensation committeethe Compensation Committee were Mark A. Goldsmith, Peter Svennilson,who serves as chair, Elizabeth G. Tréhu, Robert Tepper, and Elizabeth Trehu.James E. Audia. Mark A. Goldsmith and Robert TepperElizabeth G. Tréhu were members of the compensation committeeCompensation Committee for the entirety of 2019.  Elizabeth Trehu joined the compensation committee in March 2019.2020.  Mr. SvennilsonTepper stepped down as chair and a member of the compensation committeeCompensation Committee effective as of the end of his term as a director at the 20192020 annual meeting, and was replaced by Dr. Goldsmith as chair. Dr. Tepper will step down fromJames E. Audia joined the compensation committeeCompensation Committee as of the end of his term as a director at the Annual Meeting.   Our compensation committeeJuly 31, 2020.   The Compensation Committee met two (2)five (5) times during 2019,2020 and acted by written consent twelvethirteen times during 2019. Our compensation committee’s2020.  The Compensation Committee’s responsibilities include:

Narrative Disclosure to Summary Compensation Table

During the past fiscal year, the Compensation Committee retained Radford, an AON Hewitt Company, or Radford, a international compensation consulting firm, because of its reputation and extensive experience advising similarly situated companies. The Compensation Committee requested that Radford establish a compensation peer group; assess our executive compensation program and develop recommendations covering salary, bonus, incentive and equity compensation; review the peer group’s long-term incentive compensation trends; assist with governance related matters and risk-assessment; review and assist in designing an equity compensation strategy for non-officer employees; review and provide the committee advice regarding executive employment agreements, severance benefits and payments upon a change in control; and review our director compensation program. Radford ultimately developed recommendations that were presented to the Compensation Committee for its consideration. Following an active dialogue with Radford, the Compensation Committee approved the recommendations.

TableGrants of ContentsPlan Based Awards

The Compensation Committee is expected to make mostfollowing table sets forth certain information regarding grants of the significant adjustments to annual compensation, determine bonus and equityplan-based awards and establish new performance objectives at one or more meetings held during the first quarter of the year. However, the Compensation Committee may also consider matters related to individual compensation, such as compensation for new executive hires, as well as high-level strategic issues, such as the efficacy of our compensation strategy, potential modifications to that strategy and new trends, plans or approaches to compensation, at various meetings throughout the year. Generally, the Compensation Committee’s process comprises two related elements: the determination of compensation levels and the establishment of performance objectives for the current year. For executives other than the Chief Executive Officer, the Compensation Committee solicits and considers evaluations and recommendations submitted to the Committee by the Chief Executive Officer. In the case of the Chief Executive Officer, the evaluation of his performance is conducted by the Compensation Committee, which determines any adjustments to his compensation as well as awards to be granted. For all executives and directors as part of its deliberations, the Compensation Committee may review and consider, as appropriate, materials such as total compensation that may become payable to executives in various hypothetical scenarios, executive and director stock ownership information, company stock performance data, analyses of historical executive compensation levels and current Company-wide compensation levels and recommendations of the Compensation Committee’s compensation consultant, including analyses of executive and director compensation paid at other peer companies identified by the consultant.

Base Salary. We use base salaries to recognize the experience, skills, knowledge and responsibilities required of all our employees, including our named executive officers. None of our named executive officers is currently party to an employment agreement or other agreement or arrangement that provides for automatic or scheduled increases in base salary. In 2018 and 2019, Mr. Raythatha’s annual base salary was $465,000 and $486,000, respectively.  In February 2020 our board of directors set Mr. Raythatha’s base salary at $550,000. In 2018 and 2019, Ms. Reeve’s base salary was $355,000 and $376,478, respectively. In February 2020 our board of directors set Ms. Reeve’s base salary at $400,000. In 2018 and 2019, Dr. Senderowicz’s annual base salary was $396,544 and $410,000, respectively. In February 2020 our board of directors set Dr. Senderowicz’s base salary at $426,375.

Annual Bonus. Our board of directors may, in its discretion, award bonusesmade to our named executive officers from time to time. Our letter agreementsduring the year ended December 31, 2020.

Grants of Plan-Based Awards for Fiscal Year Ended December 31, 2020

Employment Arrangements with our named executive officers provide that they will beNamed Executive Officers

Jigar Raythatha. In connection with hiring Mr. Raythatha as our President and Chief Executive Officer, we entered into a letter agreement with Mr. Raythatha, dated March 13, 2017. Mr. Raythatha currently receives an annual base salary of $600,000 and is eligible for an annual performance-based bonuses up to a specified percentagecash incentive award targeted at 55% of theirhis annual base salary, both of which are subject to approval by our boardadjustment at the discretion of directors. Mr. Raythatha,the Compensation Committee.

Emma Reeve. In connection with hiring Ms. Reeve as our Chief Financial Officer, we entered into a letter agreement with Ms. Reeve dated August 30, 2017. Ms. Reeve currently receives a base salary of $430,000 and is eligible for an annual cash incentive award targeted at 40% of her annual base salary, both of which are subject to adjustment at the discretion of the Compensation Committee.    

Karen Valentine. In connection with hiring Ms. Valentine as our Chief Legal Officer and General Counsel, we entered into a letter agreement with Ms. Valentine dated July 21, 2018. Ms. Valentine currently receives a base salary of $402,800 and is eligible for an annual cash incentive award targeted at 40% of her annual base salary, both of which are subject to adjustment at the discretion of the Compensation Committee

Patrick Trojer.  Dr. Trojer has held a number of scientific positions at the Company from April 2008 through November 2018, when he was appointed Chief Scientific Officer. Dr. Trojer currently receives a base salary of $415,350 and is eligible for an annual cash incentive award targeted at 40% of his annual base salary. In October 2017, the Company and Dr. Senderowicz are eligible, atTrojer entered into a letter agreement, pursuant to which the sole discretion of our board of directors, to earn an annual bonus of 50%, 40% and 40%, respectively, of his or her base salary.  Performance-based bonuses, which are calculated as a percentage of base salary, are designed to motivate our employees to achieve annual goals based on our strategic, financial and operating performance objectives. From time to time, our board of directors has approved discretionary annual cash bonuses to our named executive officersCompany provided Dr. Trojer with respect to their prior year performance.

With respect to 2018, our board of directors awarded bonuses of $203,000, $142,000 and $142,000 to Mr. Raythatha, Ms. Reeve, and Dr. Senderowicz, respectively. With respect to 2019, our board of directors awarded bonuses of $290,000, $187,007 and $187,886 to Mr. Raythatha, Ms. Reeve, and Dr. Senderowicz, respectively.

Equity Incentives. Although we do not have a formal policy with respect to the grant of equity incentive awards to our executive officers, or any formal equity ownership guidelines applicable to them, we believe that equity grants provide our executives with a strong link to our long-term performance, create an ownership culture and help to align the interests of our executives and our stockholders. In addition, we believe that equity grants with a time-based vesting feature promote executive retention because this feature incents our executive officers to remain in our employment during the vesting period. Accordingly, our board of directors periodically reviews the equity incentive compensation of our named executive officers and from time to time may grant equity incentive awards to them in the form of stock options.

In March 2018, we granted options to purchase 141,929, 37,696 and 37,696 shares of our common stock to Mr. Raythatha, Ms. Reeve and Dr. Senderowicz, respectively, and in April 2018, we granted additional options to purchase 141,929, 37,696 and 37,696 shares of our common stock to Mr. Raythatha, Ms. Reeve and Dr. Senderowicz, respectively. Our board of directors has also granted options to purchase 306,938, 46,811 and 19,075 shares of our common stock to Mr. Raythatha, Ms. Reeve and Dr. Senderowicz, respectively, effective upon the commencement of trading of our common stock on the Nasdaq Stock Market in July 2018. In March 2019, we granted additional options to

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purchase 245,000, 85,500, and 93,000 shares of our common stock to Mr. Raythatha, Ms. Reeve and Dr. Senderowicz, respectively.  In February 2020, we granted additional options to purchase 200,000, 60,000, and 50,000 shares of our common stock to Mr. Raythatha, Ms. Reeve and Dr. Senderowicz, respectively. The options granted in March 2018, April 2018, July 2018, March 2019 and February 2020 vest in equal quarterly installments over a term of four years from the date of grant.

Prior to our initial public offering in July 2018, our executives were eligibleright to participate in our 2008 Stock Incentive Plan, as amendedthe severance benefits summarized below under the heading “Estimated Payments and restated to date,Benefits upon Termination without Cause or for Good Reason (Not Upon Change in Control)” and “Estimated Payment and Benefits upon Change in Control”, consistent with the 2008 Plan. During 2018 prior to our initial public offering, all stock options were granted pursuantterms that are available to the 2008 Plan. Followingother named executive officers.

Jeffrey Humphrey.  In connection with hiring Dr. Humphrey as our initial public offeringChief Medical Officer, we entered into a letter agreement with Dr. Humphrey dated June 29, 2020. Dr. Humphrey currently receives a base salary of $457,101 and is eligible for an annual cash incentive award targeted at 40% of his annual base salary.  Under the terms of Dr. Humphrey’s letter agreement, he received a cash sign-on bonus of $25,000, which was paid in July, 2018, our employees2020, as well as relocation assistance in a net amount of $75,000, which was grossed up to $121,650 for income taxes and executivespaid in July 2020, which amounts are eligiblesubject to receive stock options and other stock-based awards pursuant to our 2018 Equity Incentive Plan,repayment if Dr. Humphrey’s employment is terminated by the Company for “cause” or the 2018 Plan.

We use stock options to compensate our executive officersby Dr. Humphrey for “good reason” (each, as defined in the form of initial grants in connection with the commencement of employment and also at various times, often but not necessarily annually, if we have performed as expected or better than expected. The awards of stock options to our executive officers are made by our board of directors or compensation committee. None of our executive officers is currently party to an employment agreement that provides for automatic award of stock options. We have granted stock options to our executive officers with time-based vesting. The new hire options that we have granted to our executive officers typically become exercisable as to 25% of the shares underlying the option onhis offer letter) before the first anniversary and the second anniversary of his start date, respectively. Dr. Humphrey was also granted an option to purchase 133,000 shares of the grant date and as toCompany’s common stock, with an additional 6.25% of the original number of shares underlying the option quarterly thereafter.  The annual option grants typically become exercisable as to 6.25% of the original number of shares quarterly.   Vesting rights cease upon termination of employment and exercise rights cease shortly after termination, except that vesting is fully accelerated upon certain terminations in connection with a change of control and exercisability is extended in the case of death or disability. Prior to the exercise of an option, the holder has no rights as a stockholder with respect to the shares subject to such option, including no voting rights and no right to receive dividends or dividend equivalents.

We have historically granted stock options with exercise prices that areprice equal to the fair market value of our common stock on the date of grant.  Prior to our initial public offering in July 2018, the fair market value was determined by our board of directors, based on a number of objective and subjective factors. The exercise price of all stock options granted since our initial public offering is equal to the fair market value of shares of our common stock on the date of grant, which has been determined by reference to the closing market price of our common stockwas on the date of grant.July 7, 2020.  

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Outstanding Equity Awards at 20192020 Fiscal Year End

The following table sets forth information regarding outstanding equity awards held by our named executive officers as of December 31, 2019,2020, which consisted entirely of stock options.