As filed with the Securities and Exchange Commission on April 1, 2019May 6, 2022.

RegistrationNo. 333-            

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

FORMS-3

REGISTRATION STATEMENT

UnderUNDER

The Securities Act ofTHE SECURITIES ACT OF 1933

UNUM THERAPEUTICSCOGENT BIOSCIENCES, INC.

(Exact name of registrant as specified in its charter)

200 CambridgeParkCambridge Park Drive, Suite 31002500

Cambridge, Massachusetts 02140

(617)945-5576

(Address, including zip code, and telephone number, including area code, of registrant’s principal executive offices)

Charles WilsonAndrew Robbins

President and Chief Executive Officer and President

Unum TherapeuticsCogent Biosciences, Inc.

200 Cambridge Park Drive, Suite 31002500

Cambridge, Massachusetts 02140

(617)945-5576

(Name, address, including zip code, and telephone number, including area code, of agent for service)

Copies to:

Kingsley L. Taft, Esq.Ryan A. Murr

Danielle Lauzon, Esq.Branden C. Berns

Goodwin ProcterGibson, Dunn & Crutcher LLP

100 Northern Avenue555 Mission Street

Boston, Massachusetts 02210San Francisco, CA 94105

(617)570-1000(415) 393-8373

Approximate date of commencement of proposed sale to the public:

From time to time after the effective date of this registration statement.statement becomes effective.

If the only securities being registered on this Form are being offered pursuant to dividend or interest reinvestment plans, please check the following box.  ☐

If any of the securities being registered on this Form are to be offered on a delayed or continuous basis pursuant to Rule 415 under the Securities Act of 1933, as amended, other than securities offered only in connection with dividend or interest reinvestment plans, check the following box:  ☒

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, please check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a post-effective amendment filed pursuant to Rule 462(c) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering.  ☐

If this Form is a registration statement pursuant to General Instruction I.D. or a post-effective amendment thereto that shall become effective upon filing with the Commission pursuant to Rule 462(e) under the Securities Act, check the following box.  ☐

If this Form is a post-effective amendment to a registration statement filed pursuant to General Instruction I.D. filed to register additional securities or additional classes of securities pursuant to Rule 413(b) under the Securities Act, check the following box.  ☐

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, anon-accelerated filer, a smaller reporting company, or an emerging growth company. See the definitions of “large accelerated filer,” “accelerated filer,” “smaller reporting company,” and “emerging growth company” in Rule12b-2 of the Exchange Act. (Check one):

If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 7(a)(2)(B) of the Securities Act.  ☒

CALCULATION OF REGISTRATION FEE

The registrant hereby amends this registration statement on such date or dates as may be necessary to delay its effective date until the registrant shall file a further amendment that specifically states that this registration statement shall thereafter become effective in accordance with Section 8(a) of the Securities Act of 1933, as amended, or until this registration statement shall become effective on such date as the Commission, acting pursuant to said Section 8(a), may determine.

EXPLANATORY NOTE

This registration statement contains:contains the following documents:

The base prospectus immediately follows this explanatory note. The specific terms of any securities to be offered pursuant to the base prospectus other than the shares under the sales agreement will be specified in a prospectus supplement to the base prospectus. The specific terms of the securities to be issued and sold under the sales agreement are specified in the sales agreement prospectus supplement that immediately follows the base prospectus. The $50,000,000$75,000,000 shares of common stock that may be offered, issued and sold under the sales agreement prospectus supplement is included in the $150,000,000$300,000,000 of securities that may be offered, issued and sold by usthe registrant under the base prospectus. Upon termination of the sales agreement with Guggenheim Securities, any portion of the $75,000,000 included in the sales agreement prospectus supplement that is not sold pursuant to the sales agreement will be available for sale in other offerings pursuant to the base prospectus, and if no shares of common stock are sold under the sales agreement, the full $300,000,000 of securities may be sold in other offerings pursuant to the base prospectus and a corresponding prospectus supplement.

i

The information in this prospectus is not complete and may be changed. These securitiesWe may not be soldsell these securities or accept an offer to buy these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus is not an offer to sell nor doesthese securities and it seek an offeris not soliciting offers to buy these securities in any jurisdiction where thesuch offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED APRIL 1, 2019May 6, 2022

PROSPECTUS

$150,000,000

COMMON STOCK

PREFERRED STOCK

Common StockDEBT SECURITIES

Preferred StockWARRANTS

Debt Securities

Warrants

UnitsUNITS

From time to time, we may issue, in one or more series or classes, up to $150,000,000 inan aggregate principal amountof $300,000,000 of our common stock, preferred stock, debt securities, warrants and/or units, at prices and on terms that we will determine at the time of the offering.

This prospectus provides you with a general description of the securities we may offer. A prospectus supplement containingEach time we offer securities, we will provide specific information about the terms of the securities being offered and the offering, including the compensation of any underwriter, agent or dealer, will accompanyin a supplement to this prospectus. AnyWe may also authorize one or more free writing prospectuses to be provided to you in connection with these offerings. The prospectus supplement and any related free writing prospectus may also add, update or change information contained in this prospectus. We may not sell any securities under this prospectus without delivery of the applicable prospectus supplement. If information in any prospectus supplement is inconsistent with the information in this prospectus, then the information in that prospectus supplement will apply and will supersede the information in this prospectus.

You should read this documentprospectus, the applicable prospectus supplement and any related free writing prospectus supplement or amendment carefully, as well as any documents incorporated by reference, before you invest in our securities.any of the securities being offered.

Our shares of common stock isare listed on The Nasdaq Global Select Market under the symbol “UMRX.“COGT.” The last reported sale price of our common stock on The Nasdaq Global Select Market on March 29, 2019May 2, 2022 was $4.39$6.89 per share. We recommend that you obtain current market quotations for our common stock prior to making an investment decision.

Investing in our securities involves a high degree of risk. You should review carefully the risks and uncertainties described under the heading “Risk Factors” contained in this prospectus beginning on page 25 and any applicable prospectus supplement, and under similar headings in the other documents that are incorporated by reference into this prospectus.

NEITHER THE SECURITIES AND EXCHANGE COMMISSION NOR ANY OTHER REGULATORY BODY HAS APPROVED OR DISAPPROVED OF THESE SECURITIES OR PASSED UPON THE ACCURACY OR ADEQUACY OF THIS PROSPECTUS. ANY REPRESENTATION TO THE CONTRARY IS A CRIMINAL OFFENSE.

The dateNeither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

Prospectus dated                , 20192022

TABLE OF CONTENTSTable of Contents

ABOUT THIS PROSPECTUS

This prospectus is a part of a registration statement on FormS-3 that we filed with the Securities and Exchange Commission (the “SEC” or SEC,the “Commission”) utilizing a “shelf” registration process. Under this shelf registration process, we may sell any combination of the securities described in this prospectus in one or more offerings up to a total aggregate offering pricedollar amount of $150,000,000.$300,000,000. This prospectus provides you with a general description of the securities we may offer.

Each time we sell securities under this prospectus, we will provide a prospectus supplement that will contain specific information about the terms of that offering. We may also authorize one or more free writing prospectuses to be provided to you that may contain material information relating to these offerings. The prospectus supplement and any related free writing prospectus that we may authorize to be provided to you may also add, update or change information contained in this prospectus or in any documents that we have incorporated by reference into this prospectus. You should carefully read both this prospectus and any prospectus supplement together with additional information under the headings “Where You Can Find More Information” and “Incorporation by Reference.”

You should rely only on the information contained in or incorporated by reference in this prospectus, any accompanying prospectus supplement or in any related free writing prospectus filed by usWe have not authorized anyone to provide you with the SEC. Neither we, nor any agent, underwriter or dealer has authorized any person to give any information or to make any representation other than thosethat contained or incorporated by reference in this prospectus and any applicable prospectus supplement, oralong with the information contained in any related free writing prospectus prepared by or on behalf of us or to whichprospectuses we have referredauthorized for use in connection with a specific offering. We take no responsibility for, and can provide no assurance as to the reliability of, any other information that others may give you. This prospectus is an offer to sell only the securities offered hereby, but only under circumstances and in jurisdictions where it is lawful to do so. This prospectus, any applicable supplement to this prospectus or any related free writing prospectus do not constitute an offer to sell or the solicitation of an offer to buy any securities other than the registered securities to which they relate, nor do this prospectus, any applicable supplement to this prospectus or any related free writing prospectus constitute an offer to sell or the solicitation of an offer to buy securities in any jurisdiction to any person to whom it is unlawful to make such offer or solicitation in such jurisdiction.

You should not assume that the information contained in this prospectus, any applicable prospectus supplement or any related free writing prospectus is accurate on any date subsequent to the date set forth on the front of the document or that any information we have incorporated by reference is correct on any date subsequent to the date of the document incorporated by reference, even though this prospectus, any applicable prospectus supplement or any related free writing prospectus is delivered, or securities are sold, on a later date.

Unless the context otherwise requires, we use the terms “Unum,“Cogent,” “company,” “we,” “us,” and “our” in this prospectus to refer to Unum TherapeuticsCogent Biosciences, Inc. and, where appropriate, our subsidiary.subsidiaries.

RISK FACTORS

Investing in our securities involves a high degree of risk. You should carefully review the risks and uncertainties described under the heading “Risk Factors” contained in the applicable prospectus supplement and any related free writing prospectus, and under similar headings in our Annual Report on Form10-K for the year ended December 31, 2018, as updated by our subsequent annual, quarterly and other reports and documents that we file with the SEC that are incorporated by reference into this prospectus, before deciding whether to purchase any of the securities being registered pursuant to the registration statement of which this prospectus is a part. Each of the risk factors could adversely affect our business, operating results and financial condition, as well as adversely affect the value of an investment in our securities, and the occurrence of any of these risks might cause you to lose all or part of your investment. This prospectus and the documents incorporated herein by reference also contain forward-looking statements that involve risks and uncertainties.

PROSPECTUS SUMMARYTHE COMPANY

This summary highlightsWe are a biotechnology company focused on developing precision therapies for genetically defined diseases. Our approach is to design rational precision therapies that treat the underlying cause of disease and improve the lives of patients. Our most advanced program is bezuclastinib (also known as CGT9486), a selective tyrosine kinase inhibitor designed to potently inhibit the KIT D816V mutation as well as other mutations in KIT exon 17. KIT D816V is responsible for driving Systemic Mastocytosis (SM), a serious disease caused by unchecked proliferation of mast cells. Exon 17 mutations are also found in patients with advanced gastrointestinal stromal tumors (GIST), a type of cancer with strong dependence on oncogenic KIT signaling. Bezuclastinib is a highly selective and potent KIT inhibitor with the potential to provide a new treatment option for these patient populations. In addition to bezuclastinib, our research team is developing a portfolio of novel targeted therapies to help patients fighting serious, genetically driven diseases, initially targeting FGFR2 and ErbB2.

For more information contained elsewhereabout our business, please see our most recent Annual Report on Form 10-K, as supplemented and updated by subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K that we have filed or will file with the SEC, and in this prospectus, orother documents which are incorporated by reference into this prospectus. It might not contain all the information that is important to you. You should read the entire prospectus carefully, including the section entitled “Risk Factors” and our financial statements and the related notes included elsewhere in this prospectus or incorporated by reference into this prospectus, before making an investment decision.

Overview

We are a clinical-stage biopharmaceutical company focused on the development and commercialization of novel immunotherapy products designed to harness the power of a patient’s immune system to cure cancer. Our proprietary technologies include a universal, engineered cell therapy, referred to as Antibody-Coupled T cell Receptor (ACTR), that is intended to be used in combination with a wide range of tumor-specific antibodies to target different tumor types. In addition, we have developed a second novel technology,Bolt-On Chimeric Receptor (BOXR), for improving T cell functionality in solid tumor cancer applications by overcoming immunosuppressive tumor microenvironments. BOXR T cells may be directed to attack tumor cells using a variety of targeting strategies and our efforts to date have demonstrated activity using either ACTR or scFv-based CAR receptors. Our vision is to use our ACTR and BOXR product candidates to transform cancer treatment and deliver patient cures in many different hematologic and solid tumor cancers, improving upon current therapies.

We have a broad product pipeline that includes five programs. Four clinical-stage programs are based on the ACTR platform, composed of either ACTR087 or ACTR707 T cellsco-administered with approved and investigational antibodies. ACTR087 is our original ACTR construct, comprising the ectodomain of CD16, the costimulatory domain of4-1BB, and the signaling domain ofCD3-zeta. ACTR707 is a modified ACTR construct selected for improved performance across a number of dimensions, including increased proliferation, cytokine secretion, and persistence in a repeat stimulation test. ACTR707 differs from ACTR087 in terms of its costimulatory domain (CD28) and other structural components. Our most advanced programs are comprised of ACTR087 or ACTR707 used in combination with rituximab to treat adult patients with relapsed or refractory CD20+non-Hodgkin lymphoma (r/r NHL). These combinations are being tested in two ongoing, multi-center, open-label Phase I clinical trials calledATTCK-20-2 andATTCK-20-03.

We completed patient enrollment and dosing of ACTR707 in combination with rituximab in the first two dose levels of theATTCK-20-03 trial and presented preliminary data from these dose levels at the Sixtieth annual American Society of Hematology (ASH) meeting in December 2018 (2018 ASH Meeting). We have subsequently completed enrollment of patients in the third dose level of this trial and initiated enrollment at the fourth dose level. In 2019, we expect to define a recommended phase II dose (RP2D) based upon analysis of the cohorts tested during the dose escalation phase of the trial and to initiate a cohort expansion at the preliminary RP2D in the second half of 2019.

In the fourth quarter of 2017, we completed patient enrollment and dosing of ACTR087 in combination with rituximab in the dose escalation phase of theATTCK-20-2 trial, and in the second quarter of 2018 we initiated the cohort expansion phase of the trial using an optimized dose of ACTR087. We completed enrollment in the cohort expansion phase of theATTCK-20-2 study in the first quarter of 2019. Preliminary data from the dose escalation phase of theATTCK-20-2 trial were presented on December 2017 at the Fifty-Ninth annual ASH meeting (2017 ASH Meeting). In both Phase I trials, we believe that we have demonstrated clinical proof of concept, as evidenced by ACTR T cell expansion and persistence, a favorable tolerability profile at defined dose levels, and anti-tumor activity. Based on emerging clinical data from the Phase IATTCK-20-03 trial, the continuing progress in that trial, and our desire to efficiently manage resources, we have selected ACTR707 used in combination with rituximab to be the lead lymphoma program for advancement to further clinical development. We plan to report data on all enrolled patients in theATTCK-20-2 trial at the end of 2019.

We may take advantageRISK FACTORS

Investing in our securities involves risks. You should carefully consider the risks, uncertainties and other factors described in our most recent Annual Report on Form 10-K, as supplemented and updated by subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K that we have filed or will file with the SEC, and in other documents which are incorporated by reference into this prospectus, as well as the risk factors and other information contained in or incorporated by reference into any accompanying prospectus supplement before investing in any of our securities. Our business, financial condition, results of operations, cash flows or prospects could be materially and adversely affected by any of these exemptions for up to five years or such earlier time that we are no longer an emerging growth company. We would cease to be an emerging growth company onrisks. The risks and uncertainties described in the date that is the earliest of (i) the last day of the fiscal year in which we have total annual gross revenues of $1.07 billion or more; (ii) the last day of our fiscal year following the fifth anniversary of the date of the completion of our IPO; (iii) the date on which we have issued more than $1 billion in nonconvertible debt during the previous three years; or (iv) the date on which we are deemed to be a large accelerated filer under the rules of the Securities and Exchange Commission (SEC). We may choose to take advantage of some but not all of these exemptions. We have taken advantage of reduced reporting requirements in this prospectus. Accordingly, the information containeddocuments incorporated by reference herein may be different from the information you receive from other public companies in which you hold stock.

We have irrevocably elected to “opt out” of the exemption for the delayed adoption of certain accounting standards and, therefore, will be subject to the same new or revised accounting standards as other public companies that are not emerging growth companies.the only risks and uncertainties that you may face.

For more information about our SEC filings, please see “Where You Can Find More Information” and “Incorporation of Certain Information by Reference.”

USE OF PROCEEDS

We intend towill retain broad discretion over the use of the net proceeds from the sale of anythe securities offered underhereby. Unless otherwise specified in a prospectus supplement accompanying this prospectus, the net proceeds from the sale by us of the securities to which this prospectus relates will be used for general corporate purposes unless otherwise indicated in the applicable prospectus supplement. General corporate purposes may include, but are not limiteddevelopment, regulatory and commercial preparation activities relating to researchbezuclastinib and development costs, including the conduct of one or more clinical trials and process development and manufacturing of ourother product candidates, potential strategic acquisitions of complementary businesses, services or technologies, expansion of our technology infrastructure and capabilities,as well as for working capital capital expenditures and other general corporate purposes. We may temporarily investOur expected use of proceeds from the sale of the securities offered hereby represents our current intentions based on our present plans and business condition. As of the date of this prospectus, we cannot predict with certainty all of the particular uses for the proceeds to be received from the sale of the securities offered hereby or the amounts that we will actually spend on the uses set forth above.

Pending the use of the net proceeds, we may invest the proceeds in a varietyinterest-bearing, investment-grade securities, certificates of capital preservation instruments, including investment grade, interest bearing instrumentsdeposit or government securities. When we offer and U.S. governmentsell the securities until they are used for their stated purpose. We have not determinedto which this prospectus relates, the amountprospectus supplement related to such offering will set forth our intended use of netthe proceeds, to be used specifically forif any, received from the sale of such purposes. As a result, management will retain broad discretion over the allocation of net proceeds.securities.

DIVIDEND POLICY

We have never declared or paid cash dividends on our capital stock. We intend to retain all available funds and any future earnings to fund the growth and development of our business. We do not intend to pay cash dividends to our stockholders in the foreseeable future. In addition, pursuant to our loan and security agreement with Pacific West Bank (PWB), we are prohibited from paying cash dividends without the prior written consent of PWB. Moreover, any future indebtedness that we may incur could preclude us from paying dividends. Any future determination to pay dividends will be made at the discretion of our board of directors. Investors should not purchase our common stock with the expectation of receiving cash dividends.

SECURITIES WE MAY OFFER

This prospectus contains summary descriptions of the securities we may offer from time to time. These summary descriptions are not meant to be complete descriptions of each security. The particular terms of any security will be described in the applicable prospectus supplement.

DESCRIPTION OF CAPITAL STOCK

The following descriptions are summariesis a summary of the material terms of our capital stock, as well as other material terms of certain provisions of Delaware law, our third amended and restated certificate of incorporation and(as amended from time to time, our “certificate of incorporation”), and restated bylaws. We refer in this section to our amended and restated bylaws (“bylaws”). Our certificate of incorporation is incorporated by reference as an exhibit to our most recent Annual Report on Form 10-K filed with the SEC, as amended by certificates of amendment filed as exhibits to our current reports on Form 8-K filed on October 5, 2020 and November 9, 2020. Our bylaws are incorporated by reference as an exhibit to our current report on Form 8-K filed with the SEC on October 5, 2020. This summary does not purport to be complete and is qualified in its entirety by the provisions of our certificate of incorporation and we refer tobylaws. For more information on how you can obtain our amendedcertificate of incorporation and restated bylaws, as our bylaws.

Generalsee the heading “Where You Can Find More Information.”

Our authorized capital stock consists of 150,000,000 shares of common stock, par value $0.001 per share, and 10,000,000 shares of preferred stock, par value $0.001 per share, all1,000,000 of which are designated as Series A Non-Voting Convertible Preferred Stock (the “Series A Preferred Stock”) and 9,000,000 of which shares of preferred stock are undesignated.

As of December 31, 2018, 30,057,970 shares of our common stock were outstanding and held by 7 stockholders of record. In addition, as of December 31, 2018, we had outstanding options to purchase 3,661,982 shares of our common stock under our 2018 Stock Option and Incentive Plan, at a weighted average exercise price of $5.92 per share, 2,086,091 of which were exercisable.

Common Stock

The holders of our common stock are entitled to one vote for each share held on all matters submitted to a vote of the stockholders. The holders of our common stock do not have any cumulative voting rights. Holders of our common stock are entitled to receive ratably any dividends declared by our board of directors out of funds legally available for that purpose, subject to any preferential dividend rights of any outstanding preferred stock. Our common stock has no preemptive rights, conversion rights, or other subscription rights or redemption or sinking fund provisions.

In the event of our liquidation, dissolution, or winding up, holders of our common stock will be entitled to share ratably in all assets remaining after payment of all debts and other liabilities and any liquidation preference of any outstanding preferred stock. The shares to be issued by us in this offering will be, when issued and paid for, validly issued, fully paid andnon-assessable.

All outstanding shares of common stock are validly issued, fully paid and nonassessable, and any issued shares of common stock will be validly issued, fully paid and nonassessable.

Series A Preferred Stock

Holders of Series A Preferred Stock are entitled to receive dividends on shares of Series A Preferred Stock equal to, on an as-if-converted-to-common-stock basis, and in the same form as dividends actually paid on shares of the common stock. Except as otherwise required by law, the Series A Preferred Stock does not have voting rights. However, as long as any shares of Series A Preferred Stock are outstanding, we will not, without the affirmative vote of the holders of a majority of the then outstanding shares of the Series A Preferred Stock, (a) alter or change adversely the powers, preferences or rights given to the Series A Preferred Stock, (b) alter or amend its certificate of designation (“Certificate of Designations”), (c) amend its certificate of incorporation or other charter documents in any manner that adversely affects any rights of the holders of Series A Preferred Stock, (d) increase the number of authorized shares of Series A Preferred Stock, (e) prior to the stockholder approval of the conversion of the Series A Preferred Stock into shares of common stock (which stockholder approval has been received) or at any time while at least 40% of the originally issued Series A Preferred Stock remains issued and outstanding, consummate a Fundamental Transaction (as defined in the Certificate of Designation) or (f) enter into any agreement with respect to any of the foregoing. The Series A Preferred Stock does not have a preference upon any liquidation, dissolution or winding-up of the Company, and are not be redeemable.

Each share of Series A Preferred Stock is convertible into shares of common stock at any time at the option of the holder thereof, into 250 shares of common stock, subject to certain limitations, including that a holder of Series A Preferred Stock is prohibited from converting shares of Series A Preferred Stock into shares of common stock if, as a result of such conversion, such holder, together with its affiliates, would beneficially own more than a specified percentage (as established by the holder between 4.9% and 19.9%) of the total number of shares of common stock issued and outstanding immediately after giving effect to such conversion (the “Beneficial Ownership Limitation”).

As of March 31, 2022, 67,991 shares of Series A Preferred Stock have been converted to common stock and 95,334 shares of Series A Preferred Stock were issued and outstanding.

Preferred Stock

Our board of directors has the authority, without further action by our stockholders, to issue up to 10,000,0009,000,000 additional shares of preferred stock in one or more series and to fix the rights, preferences, privileges and restrictions thereof. These rights, preferences and privileges could include dividend rights, conversion rights, voting rights, terms of redemption, liquidation preferences, sinking fund terms and the number of shares constituting, or the designation of, such series, any or all of which may be greater than the rights of common stock. The issuance of our preferred stock could adversely affect the voting power of holders of common stock and the likelihood that such holders will receive dividend payments and payments upon our liquidation. In addition, the issuance of preferred stock could have the effect of delaying, deferring or preventing a change in control of our company or other corporate action. No shares of preferred stock are outstanding, and we have no present plan to issue any shares of preferred stock.

Registration Rights

The holdersCertain Provisions of 4,513,028 sharesDelaware Law and Our Certificate of our common stock are entitled to rights with respect to the registration of such securities as set forth below under the Securities Act. These rights are provided under the terms of an amendedIncorporation and restated investors’ rights agreement between us and certain holders our common stock. The amended and restated investors’ rights agreement includes demand registration rights, short-form registration rights, and piggyback registration rights. All fees, costs and expenses of underwritten registrations under these

Section 203 defines a business combination to include:

The amendment of any of these provisions, with the exception of the ability of our board of directors to issue shares of preferred stock and designate any rights, preferences, and privileges thereto, would require the affirmative vote of the holders of at least 66.67% of the voting power of all of our then outstanding common stock.

DESCRIPTION OF DEBT SECURITIES

The paragraphs below describe the general terms and provisions of the debt securities we may issue. When we offer to sell a particular series of debt securities, we will describe the specific terms of the securities in a supplement to this prospectus, including any additional covenants or changes to existing covenants relating to such series. The prospectus supplement also will indicate whether the general terms and provisions described in this prospectus apply to a particular series of debt securities. You should read the actual indenture if you do not fully understand a term or the way we use it in this prospectus.

We may offer senior or subordinated debt securities. Each series of debt securities may have different terms. The senior debt securities will be issued under one or more senior indentures, dated as of a date prior to such issuance, between us and the trustee identified in the applicable prospectus supplement, as amended or supplemented from time to time. We will refer to any such indenture throughout this prospectus as the “senior indenture.” Any subordinated debt securities will be issued under one or more separate indentures, dated as of a date prior to such issuance, between us and the trustee identified in the applicable prospectus supplement, as amended or supplemented from time to time. We will refer to any such indenture throughout this prospectus as the “subordinated indenture” and to the trustee under the senior or subordinated indenture as the “trustee.” The senior indenture and the subordinated indenture are sometimes collectively referred to in this prospectus as the “indentures.” The indentures will be subject to and governed by the Trust Indenture Act of 1939, as amended (the “Trust Indenture Act”). We included copies of the forms of the indentures as exhibits to our registration statement and they are incorporated into this prospectus by reference.

If we issue debt securities at a discount from their principal amount, then, for purposes of calculating the aggregate initial offering price of the offered securities issued under this prospectus, we will include only the initial offering price of the debt securities and not the principal amount of the debt securities.

We have summarized below the material provisions of the indentures and the debt securities, or indicated which material provisions will be described in the related prospectus supplement. The prospectus supplement relating to any particular securities offered will describe the specific terms of the securities, which may be in addition to or different from the general terms summarized in this prospectus. Because the summary in this prospectus and in any prospectus supplement does not contain all of the information that you may find useful, you should read the documents relating to the securities that are described in this prospectus or in any applicable prospectus supplement. Please read “Where You Can Find More Information” to find out how you can obtain a copy of those documents. Except as otherwise indicated, the terms of the indentures are identical. As used under this caption, the term “debt securities” includes the debt securities being offered by this prospectus and all other debt securities issued by us under the indentures.

General

The indentures:

Each indenture provides that we may, but need not, designate more than one trustee under an indenture. Any trustee under an indenture may resign or be removed and a successor trustee may be appointed to act with respect to the series of debt securities administered by the resigning or removed trustee. If two or more persons are acting as trustee with respect to different series of debt securities, each trustee shall be a trustee of a trust under the applicable indenture separate and apart from the trust administered by any other trustee. Except as otherwise indicated in this prospectus, any action described in this prospectus to be taken by each trustee may be taken by each trustee with respect to, and only with respect to, the one or more series of debt securities for which it is trustee under the applicable indenture.

The prospectus supplement for each offering will provide the following terms, where applicable:

We may issue debt securities that provide for less than the entire principal amount thereof to be payable upon declaration of acceleration of the maturity of the debt securities. We refer to any such debt securities throughout this prospectus as “original issue discount securities.” The applicable prospectus supplement will describe the United States federal income tax consequences and other relevant considerations applicable to original issue discount securities.

We also may issue indexedsecurities, including the portion of the principal amount thereof to be payable upon declaration of acceleration of the maturity of the debt securities. Payments of principal of, and premium and interest on, indexed debt securities are determined with reference to the rate of exchange between the currency or currency unit in which the debt security is denominated and any other currency or currency unit specified by us, to the relationship between two or more currencies or currency units or by other similar methods or formulas specified in the prospectus supplement.

Except as described in the indentures under “Merger,“Compliance with Consolidation or Sale of Assets”Provisions” and “Successor Entity” or as may be set forth in any prospectus supplement, the debt securities will not contain any provisions that (i) would limit our ability to incur indebtedness or (ii) would afford holders of debt securities protection in the event of (a) a highly leveraged or similar transaction involving us, or (b) a change of control or reorganization, restructuring, merger or similar transaction involving us that may adversely affect the holders of the debt securities. In the future, we may enter into transactions, such as the sale of all or substantially all of our assets or a merger or consolidation, that may have an adverse effect on our ability to service our indebtedness, including the debt securities, by, among other things, substantially reducing or eliminating our assets.

Our governing instruments do not define the term “substantially all” as it relates to the sale of assets. Additionally, Delaware cases interpreting the term “substantially all” rely upon the facts and circumstances of each particular case. Consequently, to determine whether a sale of “substantially all” of our assets has occurred, a holder of debt securities must review the financial and other information that we have disclosed to the public.

We will provide you with more information in the applicable prospectus supplement regarding any deletions, modifications, or additions to the events of default or covenants that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

Payment

Unless we give you different information in the applicable prospectus supplement, the principal of, and any premium or make-whole amount, and interest on, any series of the debt securities will be payable at the corporate trust office of the trustee. We will provide you with the address of the trustee in the applicable prospectus supplement. We may also pay interest by mailing a check to the address of the person entitled to it as it appears in the applicable register for the debt securities or by wire transfer of funds to that person at an account maintained within the United States.

Denomination, Interest, Registration and Transfer

Unless otherwise described in the applicable prospectus supplement, the debt securities of any series will be issuable in denominations of $1,000 and integral multiples of $1,000.

Subject to the limitations imposed upon debt securities that are evidenced by a computerized entry in the records of a depository company rather than by physical delivery of a note, a holder of debt securities of any series may:

Every debt security surrendered for registration of transfer or exchange must be duly endorsed or accompanied by a written instrument of transfer satisfactory to the applicable trustee or transfer agent. Payment of a service charge will not be required for any registration of transfer or exchange of any debt securities, but we or the trustee may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith. If in addition to the applicable trustee, the applicable prospectus supplement refers to any transfer agent initially designated by us for any series of debt securities, we may at any time rescind the designation of any such transfer agent or approve a change in the location through which any such transfer agent acts, except that we will be required to maintain a transfer agent in each place of payment for such series. We may at any time designate additional transfer agents for any series of debt securities.

Neither we, nor any trustee, will be required to:

Merger, Consolidation or Sale of Assets

The indentures provide that we may, without the consent of the holders of any outstanding debt securities, (i) consolidate with, (ii) sell, lease or convey all or substantially all of our assets to, or (iii) merge with or into, any other entity provided that:

Covenants

Existence. Except as described therein under “Merger, Consolidation or Sale of Assets,“Company May Consolidate, Etc.,” the indentures require us to do or cause to be done all things necessary to preserve and keep in full force and effect our existence, rights and franchises. However, the indentures do not require us to preserve any right or franchise if we determine that any right or franchise is no longer desirable in the conduct of our business.

Payment of taxes and other claims. The indentures require us to pay, discharge or cause to be paid or discharged, before they become delinquent (i) all taxes, assessments and governmental charges levied or imposed on us, and (ii) all lawful claims for labor, materials and supplies which, if unpaid, might by law become a lien upon our property. However, we will not be required to pay, discharge or cause to be paid or discharged any such tax, assessment, charge or claim whose amount, applicability or validity is being contested in good faith by appropriate proceedings.

Provision of financial information. The indentures require us to (i) within 1530 days of each of the respective dates by which we are required to file our annual reports, quarterly reports and other documents with the SEC, file with the trustee copies of the annual report, quarterly report and other documents that we file with the SEC under Section 13 or 15(d) of the Exchange Act and (ii) file with the trustee and the SEC any additional information, documents and reports regarding compliance by us with the conditions and covenants of the indentures, as required, (iii) within 30 days after the filing with the trustee, mail to all holders of debt securities, as their names and addresses appear in the applicable register for such debt securities, without cost to such holders, summaries of any documents and reports required to be filed by us pursuant to (i) and (ii) above, and (iv) supply, promptly upon written request and payment of the reasonable cost of duplication and delivery, copies of such documents to any prospective holder.required.

Additional covenants. The applicable prospectus supplement will set forth any of our additional covenants relating to any series of debt securities.

Events of Default, Notice and Waiver

Unless the applicable prospectus supplement states otherwise, when we refer to “events of default” as defined in the indentures with respect to any series of debt securities, we mean:

payment of the money due has been obtained by the applicable trustee, the holders of at least a majority in principal amount of outstanding debt securities of such series or of all debt securities then outstanding under the applicable indenture may rescind and annul such declaration and its consequences if:

The indentures also provide that the holders of at least a majority in principal amount of the outstanding debt securities of any series or of all debt securities then outstanding under the applicable indenture may, on behalf of all holders, waive any past default with respect to such series and its consequences, except a default:

The indentures require each trustee to give notice to the holders of debt securities within the later of 90 days after of a default occurs and 30 days after it is actually known to a trustee or written notice of it is received by the trustee, unless such default has been cured or waived. However, the trustee may withhold notice if specified persons of such trustee consider such withholding to be in the interest of the holders of debt securities. The trustee may not withhold notice of a default in the payment of principal, any premium or interest on any debt security of such series or in the payment of any sinking fund installment in respect of any debt security of such series.

premium, if any) and interest on the debt securities, issued under that indenture. However,as provided in the debt securities or indentures, on or after the respective due dates expressed in the debt securities or the indentures (or in the case of redemption, on the redemption date) or (ii) institute suit for the enforcement of any such payment on or after such respective dates or redemption date. Furthermore, no such modification or amendment may, without the consent of the holders of all of the debt securities affected by the modification or amendment:

the event of a distribution of assets upon insolvency, holders of subordinated debt securities may recover less, ratably, than our general creditors.

The term “senior debt” will be defined in the applicable indenture as the principal of and interest on, or substantially similar payments to be made by us in respect of, other outstanding indebtedness, whether outstanding at the date of execution of the applicable indenture or subsequently incurred, created or assumed. The prospectus supplement may include a description of additional terms implementing the subordination feature.

No restrictions will be included in any indenture relating to subordinated debt securities upon the creation of additional senior debt.

If this prospectus is being delivered in connection with the offering of a series of subordinated debt securities, the accompanying prospectus supplement or the information incorporated in this prospectus by reference will set forth the approximate amount of senior debt outstanding as of the end of our most recent fiscal quarter.

Discharge, Defeasance and Covenant Defeasance

Unless otherwise indicated in the applicable prospectus supplement, the indentures allow us to discharge our obligations to holders of any series of debt securities issued under any indenture when:

Unless otherwise indicated in the applicable prospectus supplement, the indentures provide that, upon our irrevocable deposit with the applicable trustee, in trust, of an amount, in such currency or currencies, currency unit or units or composite currency or currencies in which such debt securities are payable at stated maturity, or government obligations, or both, applicable to such debt securities, which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient to pay the principal of, and any premium or make-whole amount, and interest on, such debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates therefor, the issuing companywe may elect either:

Unless otherwise provided in the applicable prospectus supplement, if after we have deposited funds and/or government obligations to effect defeasance or covenant defeasance with respect to debt securities of any series, (i) the holder of a debt security of such series is entitled to, and does, elect under the terms of the applicable indenture or the terms of such debt security to receive payment in a currency, currency unit or composite currency other than that in which such deposit has been made in respect of such debt security, or (ii) a conversion event occurs in respect of the currency, currency unit or composite currency in which such deposit has been made, the indebtedness represented by such debt security will be deemed to have been, and will be, fully discharged and satisfied through the payment of the principal of, and premium or make-whole amount, and interest on, such debt security as they become due out of the proceeds yielded by converting the amount so deposited in respect of such debt security into the currency, currency unit or composite currency in which such debt security becomes payable as a result of such election or such cessation of usage based on the applicable market exchange rate.

Global Securities

The debt securities of a series may be issued in whole or in part in the form of one or more global securities that will be deposited with, or on behalf of, a depository identified in the applicable prospectus supplement relating to such series. Global securities, if any, issued in the United States are expected to be deposited with The Depository Trust Company or DTC,(“DTC”), as depository. We may issue global securities in either registered or bearer form and in either temporary or permanent form. We will describe the specific terms of the depository arrangement with respect to a series of debt securities in the applicable prospectus supplement relating to such series. We expect that unless the applicable prospectus supplement provides otherwise, the following provisions will apply to depository arrangements.

Once a global security is issued, the depository for such global security or its nominee will credit on its book-entry registration and transfer system the respective principal amounts of the individual debt securities represented by such global security to the accounts of participants that have accounts with such depository. Such accounts shall be designated by the underwriters, dealers or agents with respect to such debt securities or by us if we offer such debt securities directly. Ownership of beneficial interests in such global security will be limited to participants with the depository or persons that may hold interests through those participants.

purpose of receiving such payments. Consequently, neither we nor the trustee have or will have any responsibility or liability for the payment of such amounts to beneficial owners of debt securities including principal, any premium or make-whole amount, or interest. We believe, however, that it is currently the policy of DTC to immediately credit the accounts of relevant participants with such payments, in amounts proportionate to their respective holdings of beneficial interests in the relevant global security as shown on the records of DTC or its nominee. We also expect that payments by participants to owners of beneficial interests in such global security held through such participants will be governed by standing instructions and customary practices, as is the case with securities held for the account of customers in bearer form or registered in street name, and will be the responsibility of such participants. Redemption notices with respect to any debt securities represented by a global security will be sent to the depository or its nominee. If less than all of the debt securities of any series are to be redeemed, we expect the depository to determine the amount of the interest of each participant in such debt securities to be redeemed to be determined by lot. Neither we, the trustee, any paying agent nor the security registrar for such debt securities will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in the global security for such debt securities or for maintaining any records with respect thereto.

Neither we nor the trustee will be liable for any delay by the holders of a global security or the depository in identifying the beneficial owners of debt securities, and we and the trustee may conclusively rely on, and will be

DESCRIPTION OF WARRANTS

The following description, together with the additional information we may include in any applicable prospectus supplements, summarizes the material terms and provisions of the warrants that we may offer under this prospectus and the related warrant agreements and warrant certificates. While the terms summarized below will apply generally to any warrants that we may offer, we will describe the particular terms of any series of warrants in more detail in the applicable prospectus supplement. If we indicate in the prospectus supplement, the terms of any warrants offered under that prospectus supplement may differ from the terms described below. Specific warrant agreements will contain additional important terms and provisions and will be incorporated by reference as an exhibit to the registration statement, which includes this prospectus.

General

We may issue warrants for the purchase of common stock, preferred stock and/or debt securities in one or more series. We may issue warrants independently or together with common stock, preferred stock and/or debt securities, and the warrants may be attached to or separate from these securities.

We will evidence each series of warrants by warrant certificates that we will issue under a separate warrant agreement. We will enter into the warrant agreement with a warrant agent. We will indicate the name and address of the warrant agent in the applicable prospectus supplement relating to a particular series of warrants.

We will describe in the applicable prospectus supplement the terms of the series of warrants, including:

DESCRIPTION OF UNITS

We may issue units comprised of shares of common stock, shares of preferred stock, debt securities and warrants in any combination. We may issue units in such amounts and in as many distinct series as we wish. This section outlines certain provisions of the units that we may issue. If we issue units, they will be issued under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. The information described in this section may not be complete in all respects and is qualified entirely by reference to the unit agreement with respect to the units of any particular series. The specific terms of any series of units offered will be described in the applicable prospectus supplement. If so described in a particular supplement, the specific terms of any series of units may differ from the general description of terms presented below. We urge you to read any prospectus supplement related to any series of units we may offer, as well as the complete unit agreement and unit certificate that contain the terms of the units. If we issue units, forms of unit agreements and unit certificates relating to such units will be incorporated by reference as exhibits to the registration statement, which includes this prospectus.

Each unit that we may issue will be issued so that the holder of the unit is also the holder of each security included in the unit. Thus, the holder of a unit will have the rights and obligations of a holder of each included security. The unit agreement under which a unit is issued may provide that the securities included in the unit may not be held or transferred separately, at any time or at any time before a specified date. The applicable prospectus supplement may describe:

The provisions described in this section, as well as those described under “Description of Capital Stock,” “Description of Debt Securities” and “Description of Warrants” will apply to the securities included in each unit, to the extent relevant and as may be updated in any prospectus supplements.

Issuance in Series

We may issue units in such amounts and in as many distinct series as we wish. This section summarizes terms of the units that apply generally to all series. Most of the financial and other specific terms of your series will be described in the applicable prospectus supplement.

Unit Agreements

We will issue the units under one or more unit agreements to be entered into between us and a bank or other financial institution, as unit agent. We may add, replace or terminate unit agents from time to time. We will identify the unit agreement under which each series of units will be issued and the unit agent under that agreement in the applicable prospectus supplement.

The following provisions will generally apply to all unit agreements unless otherwise stated in the applicable prospectus supplement:

Modification without Consent

We and the applicable unit agent may amend any unit or unit agreement without the consent of any holder:

We do not need any approval to make changes that affect only units to be issued after the changes take effect. We may also make changes that do not adversely affect a particular unit in any material respect, even if they adversely affect other units in a material respect. In those cases, we do not need to obtain the approval of the holder of the unaffected unit; we need only obtain any required approvals from the holders of the affected units.

Modification with Consent

We may not amend any particular unit or a unit agreement with respect to any particular unit unless we obtain the consent of the holder of that unit, if the amendment would:

Any other change to a particular unit agreement and the units issued under that agreement would require the following approval:

These provisions regarding changes with majority approval also apply to changes affecting any securities issued under a unit agreement, as the governing document.

In each case, the required approval must be given by written consent.

Unit Agreements Will Not Be Qualified under Trust Indenture Act

No unit agreement will be qualified as an indenture, and no unit agent will be required to qualify as a trustee, under the Trust Indenture Act. Therefore, holders of units issued under unit agreements will not have the protections of the Trust Indenture Act with respect to their units.

sell our assets substantially as an entirety to, another corporation or other entity, the successor entity will succeed to and assume our obligations under the unit agreements. We will then be relieved of any further obligation under these agreements.

The unit agreements will not include any restrictions on our ability to put liens on our assets, nor will they restrict our ability to sell our assets. The unit agreements also will not provide for any events of default or remedies upon the occurrence of any events of default.

Governing Law

The unit agreements and the units will be governed by Delaware law.

Form, Exchange and Transfer

Unless the accompanying prospectus supplement states otherwise, we will issue each unit in global—i.e., book-entry—form only. Units in book-entry form will be represented by a global security registered in the name of a depositary, which will be the holder of all the units represented by the global security. Those who own beneficial interests in a unit will do so through participants in the depositary’s system, and the rights of these indirect owners will be governed solely by the applicable procedures of the depositary and its participants. We will describe book-entry securities, and other terms regarding the issuance and registration of the units in the applicable prospectus supplement.

Unless the accompanying prospectus supplement states otherwise, each unit and all securities comprising the unit will be issued in the same form.

If we issue any units in registered,non-global form, the following will apply to them.

The units will be issued in the denominations stated in the applicable prospectus supplement. Holders may exchange their units for units of smaller denominations or combined into fewer units of larger denominations, as long as the total amount is not changed.

PLAN OF DISTRIBUTION

We may sell the securities from time to time pursuant to underwritten public offerings, negotiated transactions, block trades or a combination of these methods. We may sell the securities to or through underwriters or dealers, through agents, or directly to one or more purchasers. We may distribute securities from time to time in one or more transactions:

We may also sell equity securities covered by this registration statement in an “at the market offering” as defined in Rule 415 under the Securities Act. Such offering may be made into an existing trading market for such securities in transactions at other than a fixed price, either:

Suchat-the-market at the market offerings, if any, may be conducted by underwriters acting as principal or agent.

A prospectus supplement or supplements (and any related free writing prospectus that we may authorize to be provided to you) will describe the terms of the offering of the securities, including, to the extent applicable:

Only underwriters named in the prospectus supplement are underwriters of the securities offered by the prospectus supplement.

If underwriters are used in the sale, they will acquire the securities for their own account and may resell the securities from time to time in one or more transactions at a fixed public offering price or at varying prices determined at the time of sale. The obligations of the underwriters to purchase the securities will be subject to the conditions set forth in the applicable underwriting agreement. We may offer the securities to the public through underwriting syndicates represented by managing underwriters or by underwriters without a syndicate. Subject to certain conditions, the underwriters will be obligated to purchase all of the securities offered by the prospectus supplement. Any public offering price and any discounts or concessions allowed orre-allowed or paid to dealers may change from time to time. We may use underwriters with whom we have a material relationship. We will describe in the prospectus supplement, naming the underwriter, the nature of any such relationship.

We may sell securities directly or through agents we designate from time to time. We will name any agent involved in the offering and sale of securities, and we will describe any commissions we will pay the agent in the prospectus supplement. Unless the prospectus supplement states otherwise, our agent will act on a best-efforts basis for the period of its appointment.

We may authorize agents or underwriters to solicit offers by certain types of institutional investors to purchase securities from us at the public offering price set forth in the prospectus supplement pursuant to delayed delivery contracts providing for payment and delivery on a specified date in the future. We will describe the conditions to these contracts and the commissions we must pay for solicitation of these contracts in the prospectus supplement.

We may provide agents and underwriters with indemnification against civil liabilities related to offerings pursuant to this offering,prospectus, including liabilities under the Securities Act, or contribution with respect to payments that the agents or underwriters may make with respect to these liabilities. Agents and underwriters may engage in transactions with, or perform services for, us in the ordinary course of business.

All securities we offer, other than our shares of common stock, will be new issues of securities with no established trading market. Any underwriters may make a market in these securities, but will not be obligated to do so and may discontinue any market making at any time without notice. We cannot guarantee the liquidity of the trading markets for any securities.

Any underwriter may engage in overallotment, stabilizing transactions, short covering transactions and penalty bids.bids in accordance with Regulation M under the Exchange Act. Overallotment involves sales in excess of the offering size, which create a short position. Stabilizing transactions permit bids to purchase the underlying security so long as the stabilizing bids do not exceed a specified maximum. Short covering transactions involve purchases of the securities in the open market after the distribution is completed to cover short positions. Penalty bids permit the underwriters to reclaim a selling concession from a dealer when the securities originally sold by the dealer are purchased in a stabilizing or covering transaction to cover short positions. Those activities may cause the price of the securities to be higher than it would otherwise be. If commenced, the underwriters may discontinue any of the activities at any time. These transactions may be effected on any exchange orover-the-counter market or otherwise.

Any underwriters who are qualified market makers on The Nasdaq Global Select Market may engage in passive market making transactions in the securities on The Nasdaq Global Select Market in accordance with Rule 103 of Regulation M, during the business day prior to the pricing of the offering, before the commencement of offers or sales of the securities. Passive market makers must comply with applicable volume and price limitations and must be identified as passive market makers. In general, a passive market maker must display its bid at a price not in excess of the highest independent bid for such security; if all independent bids are lowered below the passive market maker’s bid, however, the passive market maker’s bid must then be lowered when certain purchase limits are exceeded. Passive market making may stabilize the market price of the securities at a level above that which might otherwise prevail in the open market and, if commenced, may be discontinued at any time.

LEGAL MATTERS

Certain legal matters, in connection with this offeringincluding the legality of the securities offered, will be passed upon for us by Goodwin ProcterGibson, Dunn & Crutcher LLP, Boston, Massachusetts. Any underwriters will also be advised about the validity of the securities and other legal matters by their own counsel, which will be named in the prospectus supplement.San Francisco, California.

EXPERTS

The financial statements incorporated in this prospectus by reference to the Annual Report on Form10-K for the year ended December 31, 20182021 have been so incorporated in reliance on the report (which contains an

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, proxy statements and other information with the SEC, and we have filed with the SEC a registration statement onForm S-3 under the Securities Act with respect to the securities we are offeringoffered by this prospectus. This prospectus, which forms part of the registration statement, does not contain all of the information included in the registration statement.statement, including its exhibits and schedules. For further information pertaining toabout us and ourthe securities described in this prospectus, you should refer to the registration statement, its exhibits and to its exhibits. Whenever we make reference in this prospectus to any ofschedules and our contracts, agreements or other documents, the references are not necessarily complete, and you should refer to the exhibits attached to the registration statement for copies of the actual contract, agreement or other document.

We are subject to the informational requirements of the Exchange Act and will file annual, quarterly and current reports, proxy statements and other information with the SEC. The SEC maintains a web site (http://www.sec.gov) that contains reports, proxy andproxies, information statements and other information regarding issuers like us that file electronicallyfiled with the SEC.

Our filings are available to the public on the Internet, through a database maintained by the SEC at http://www.sec.gov. We also maintain a website atwww.unumrx.comwww.cogentbio.com. We have included our website address for the information of prospective investors and do not intend it to be an active link to our website. Information contained on our website does not constitute a part of this prospectus or any applicable prospectus supplement (or any document incorporated by reference herein or therein).

INCORPORATION BY REFERENCE

The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus.

Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended, or the Exchange Act (in each case, other than those documents or the portions of those documents not deemed to be filed) between the date of the initial registration statement and the effectiveness of the registration statement and following the effectiveness of the registration statement until the offering of the securities under the registration statement is terminated or completed:

We also incorporate by reference into this prospectus all documents (other than current reports furnished under Item 2.02 or Item 7.01 of Form8-K and exhibits filed on such form that are related to such items) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date of the initial filing of the registration statement of which this prospectus forms a part and prior to effectiveness of the registration statement, and (ii) after the date of this prospectus but prior to the termination of the offering. These documents include, without limitation, Annual Reports on Form10-K, Quarterly Reports on Form10-Q, Current Reports on Form8-K, as well as proxy statements.

You may request a copy of these filings, at no cost, by contacting us, either orally or in writing, at the following:

Unum Therapeutics Inc.

200 CambridgePark Drive, Suite 3100

Cambridge, Massachusetts 02140

(617)945-5576

$50,000,000

COMMON STOCK

Common StockPREFERRED STOCK

DEBT SECURITIES

WARRANTS

UNITS

PROSPECTUS

, 20192022

PART IIThe information in this prospectus supplement is not complete and may be changed. We may not sell these securities until the registration statement filed with the Securities and Exchange Commission is effective. This prospectus supplement is not an offer to sell these securities and is not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

SUBJECT TO COMPLETION, DATED May 6, 2022

PROSPECTUS SUPPLEMENT

(To prospectus dated                , 2022)

Up to $75,000,000

COMMON STOCK

We have entered into a sales agreement (the “Sales Agreement”) with Guggenheim Securities, LLC (“Guggenheim Securities”), dated May 6, 2022 (the “Sales Agreement”), relating to the sale of shares of our common stock offered by this prospectus supplement and the accompanying prospectus. In accordance with the terms of the Sales Agreement, under this prospectus supplement and the accompanying prospectus, we may offer and sell shares of our common stock, $0.001 par value per share, having an aggregate offering price of up to $75,000,000 from time to time through or to Guggenheim Securities, acting as our agent or principal.

Shares of our common stock are listed on The Nasdaq Global Select Market under the symbol “COGT.” On May 2, 2022, the last reported sale price of our common stock on The Nasdaq Global Select Market was $6.89 per share.

Sales of our common stock, if any, under this prospectus supplement and the accompanying prospectus will be made by any method permitted that is deemed an “at the market offering” as defined in Rule 415(a)(4) under the Securities Act of 1933, as amended (the “Securities Act”). Guggenheim Securities is not required to sell any specific amount, but will act as our sales agent using commercially reasonable efforts consistent with its normal trading and sales practices. There is no arrangement for funds to be received in any escrow, trust or similar arrangement.

Guggenheim Securities will be entitled to compensation at a commission rate of 3.0% of the gross sales price per share sold under the Sales Agreement. See “Plan of Distribution” beginning on page S-8 for additional information regarding the compensation to be paid to Guggenheim Securities. In connection with the sale of shares of our common stock on our behalf, Guggenheim Securities will be deemed to be an “underwriter” within the meaning of the Securities Act and the compensation of Guggenheim Securities will be deemed to be underwriting commissions or discounts. We have also agreed to provide indemnification and contribution to Guggenheim Securities with respect to certain liabilities, including liabilities under the Securities Act.

Investing in our common stock involves risks. You should read carefully and consider the risks referenced under “Risk Factors” beginning on page S-6 of this prospectus supplement, as well as the other information contained in or incorporated by reference in this prospectus supplement and the accompanying prospectus before making a decision to invest in our securities.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed upon the accuracy or adequacy of this prospectus supplement and the accompanying prospectus. Any representation to the contrary is a criminal offense.

Guggenheim Securities

Prospectus Supplement dated                , 2022

TABLE OF CONTENTS

ABOUT THIS PROSPECTUS SUPPLEMENT

This prospectus supplement relates to the offering of shares of our common stock. Before buying any of the shares of common stock that we are offering, we urge you to carefully read this prospectus supplement, together with the information incorporated by reference as described under the headings “Where You Can Find More Information” and “Incorporation of Certain Information by Reference” in this prospectus supplement and the accompanying prospectus, and any free writing prospectus that we have authorized for use in connection with this offering. These documents contain important information that you should consider when making your investment decision. In general, when we refer only to the prospectus, we are referring to both the prospectus supplement and the accompanying prospectus combined.

This prospectus supplement describes the terms of this offering of shares of common stock and also adds to and updates information contained in the documents incorporated by reference into this prospectus. To the extent there is a conflict between the information contained in this prospectus, on the one hand, and the information contained in any document incorporated by reference into this prospectus that was filed with the Securities and Exchange Commission (the “SEC”) before the date of this prospectus, on the other hand, you should rely on the information in this prospectus. If any statement in one of these documents is inconsistent with a statement in another document having a later date—for example, a document incorporated by reference into this prospectus—the statement in the document having the later date modifies or supersedes the earlier statement.

We have not, and Guggenheim Securities has not, authorized any other person to provide you with information that is in addition to or different from that contained or incorporated by reference in this prospectus, along with the information contained in any permitted free writing prospectuses we have authorized for use in connection with this offering. Neither we nor Guggenheim Securities takes any responsibility for, or can provide any assurance as to the reliability of, any information other than the information contained or incorporated by reference in this prospectus or any permitted free writing prospectuses we have authorized for use in connection with this offering. You should assume that the information appearing in this prospectus is accurate only as of the date on the front cover of this prospectus. Our business, financial condition, results of operations and prospects may have changed since that date.

Information Not Requiredcontained on, or accessible through, our website is not part of this prospectus. We and Guggenheim Securities are offering to sell, and seeking offers to buy, shares of common stock only in Prospectusjurisdictions where offers and sales are permitted. The distribution of this prospectus and the offering of the common stock in certain jurisdictions may be restricted by law. Persons outside the United States who come into possession of this prospectus must inform themselves about, and observe any restrictions relating to, the offering of the common stock and the distribution of this prospectus outside the United States. This prospectus does not constitute, and may not be used in connection with, an offer to sell, or a solicitation of an offer to buy, any securities offered by this prospectus by any person in any jurisdiction in which it is unlawful for such person to make such an offer or solicitation.

Unless the context otherwise requires, we use the terms “Cogent,” “company,” “we,” “us,” and “our” in this prospectus to refer to Cogent Biosciences, Inc. and, where appropriate, our subsidiaries.

RISK FACTORS

Investing in our securities involves risks. You should carefully consider the risks, uncertainties and other factors described in our most recent Annual Report on Form 10-K, as supplemented and updated by subsequent Quarterly Reports on Form 10-Q and Current Reports on Form 8-K that we have filed or will file with the SEC, and in other documents which are incorporated by reference into this prospectus, including the risk factors and other information contained in or incorporated by reference into this prospectus before investing in any of our securities. Our business, financial condition, results of operations, cash flows or prospects could be materially adversely affected by any of these risks. The risks and uncertainties described in the documents incorporated by reference herein are not the only risks and uncertainties that you may face.

Risks Relating to this Offering

We have broad discretion as to the use of proceeds from this offering and may not use the proceeds effectively.

Our management will retain broad discretion as to the allocation of the proceeds and may spend these proceeds in ways in which you may not agree. The failure of our management to apply these funds effectively could result in unfavorable returns and uncertainty about our prospects, each of which could cause the price of our common stock to decline.

If you purchase shares of our common stock in this offering, you will incur immediate and substantial dilution.

The price per share of common stock being offered may be higher than the net tangible book value per share of our outstanding common stock prior to this offering. Assuming that an aggregate of 10,885,341 shares of common stock are sold at a price of $6.89 per share, the last reported sale price of shares of our common stock on The Nasdaq Global Select Market on May 2, 2022, for aggregate gross proceeds of approximately $75,000,000 and after deducting commissions and estimated offering expenses payable by us, new investors in this offering would incur immediate dilution of $3.66 per share. In addition, you may also experience additional dilution after this offering on any future equity issuances, including the issuance of common stock in connection with the 2018 Stock Option and Incentive Plan and the 2018 Employee Stock Purchase Plan. To the extent we raise additional capital by issuing equity securities, our stockholders will experience substantial additional dilution. See “Dilution” for additional information.

The actual number of shares of common stock we will issue under the Sales Agreement, at any one time or in total, is uncertain.

Subject to certain limitations in the Sales Agreement and compliance with applicable law, we have the discretion to deliver a placement notice to Guggenheim Securities at any time throughout the term of the Sales Agreement. The number of shares of common stock that are sold by Guggenheim Securities after delivering a placement notice will fluctuate based on the market price of the shares of common stock during the sales period and limits we set with Guggenheim Securities. Because the price per share of each share sold will fluctuate based on the market price of shares of our common stock during the sales period, it is not possible at this stage to predict the number of shares of common stock that will be ultimately issued.

The shares of common stock offered hereby will be sold in “at the market offerings,” and investors who buy common stock at different times will likely pay different prices.

Investors who purchase shares of common stock in this offering at different times will likely pay different prices, and so may experience different outcomes in their investment results. We will have discretion, subject to market demand, to vary the timing, prices, and numbers of shares of common stock sold, and there is no minimum or maximum sales price. Investors may experience a decline in the value of their shares of common stock as a result of share sales made at prices lower than the prices they paid.

USE OF PROCEEDS

We will retain broad discretion over the use of the net proceeds, if any, from the sale of the securities offered hereby. We may issue and sell shares of common stock having aggregate sales proceeds of up to $75,000,000 from time to time. Because there is no minimum offering amount required as a condition to close this offering, the actual total public offering amount, commissions and proceeds to us, if any, are not determinable at this time.

We intend to use the net proceeds from the sale by us of the securities to which this prospectus supplement relates for development, regulatory and commercial preparation activities relating to bezuclastinib and other product candidates, as well as for working capital and general corporate purposes.

Pending the use of the net proceeds, we may invest the proceeds in interest-bearing, investment-grade securities, certificates of deposit or government securities.

DILUTION

Dilution represents the difference between the amount per share of common stock paid by purchasers of shares of common stock in this offering and the as-adjusted net tangible book value per share of our common stock immediately after this offering. The data in this section are derived from our balance sheet as of March 31, 2022. Net tangible book value per share of common stock is equal to our total tangible assets less the amount of our total liabilities divided by the sum of the number of shares of common stock outstanding as of March 31, 2022, excluding shares of common stock underlying outstanding options. Our net tangible book value as of March 31, 2022 was $187.9 million, or $4.10 per share of common stock. For purposes of this “Dilution” section, except as otherwise noted, all subsequent share and per share information assumes the conversion of all outstanding shares of our Series A Preferred Stock into shares of common stock without regard to the Beneficial Ownership Limitation (the “Series A Conversion”) (for more information, see “Description of Capital Stock” in the accompanying prospectus). Assuming such conversion, our pro forma net tangible book value as of March 31, 2022 was $187.9 million, or $2.70 per share of common stock.

We present dilution on a pro forma as-adjusted basis to give effect to (i) the assumed conversion of all outstanding shares of our Series A Preferred Stock as described above and (ii) our receipt of the estimated net proceeds from the sale of shares of our common stock in this offering, based on the public offering price of $6.89 per share of common stock, the last reported sale price of our common stock on The Nasdaq Global Select Market on May 2, 2022, and after deducting the underwriting discounts and commissions and estimated offering expenses payable by us. On a pro forma as-adjusted basis, our as-adjusted net tangible book value as of March 31, 2022 would have been $260.4 million, or $3.23 per share of common stock. This represents an immediate increase in pro forma as-adjusted net tangible book value to existing stockholders of $0.53 per share of common stock and immediate dilution in pro forma as-adjusted net tangible book value to purchasers of shares of common stock in this offering of $3.66 per share of common stock. The following table illustrates this dilution per share of common stock:

PLAN OF DISTRIBUTION

We have entered into a sales agreement with Guggenheim Securities under which we may issue and sell shares of common stock having an aggregate offering price of up to $75,000,000 from time to time through or to Guggenheim Securities as our sales agent or principal. Sales of shares of common stock, if any, under this prospectus will be by any method that is deemed to be an “at the market offering,” as defined in Rule 415 under the Securities Act. If authorized by us in writing, Guggenheim Securities may purchase shares of our common stock as principal.

Guggenheim Securities will offer shares of our common stock subject to the terms and conditions of the sales agreement on a daily basis or as otherwise agreed upon by us and Guggenheim Securities. We will designate the maximum amount of common stock to be sold through Guggenheim Securities on a daily basis or otherwise determine such maximum amount together with Guggenheim Securities. Subject to the terms and conditions of the sales agreement, Guggenheim Securities will use its commercially reasonable efforts consistent with its normal trading and sales practices to sell on our behalf all of the shares of common stock requested to be sold by us. We may instruct Guggenheim Securities not to sell shares of common stock if the sales cannot be effected at or above the price designated by us in any such instruction. Guggenheim Securities or we may suspend the offering of shares of our common stock being made through Guggenheim Securities under the sales agreement upon proper notice to the other party. Guggenheim Securities and we each have the right, by giving written notice as specified in the sales agreement, to terminate the sales agreement in each party’s sole discretion at any time. The offering of shares of our common stock pursuant to the sales agreement will otherwise terminate upon the termination of the sales agreement as provided therein.

The aggregate compensation payable to Guggenheim Securities as sales agent will be an amount equal to 3.0% of the gross proceeds of any shares sold through it pursuant to the sales agreement. We have also agreed to reimburse Guggenheim Securities up to $50,000 of Guggenheim Securities’ actual outside legal expenses incurred in connection with this offering. We estimate that the total expenses of the offering payable by us, excluding commissions payable to Guggenheim Securities under the sales agreement, will be approximately $200,000.

The remaining sales proceeds, after deducting any expenses payable by us and any transaction fees imposed by any governmental, regulatory, or self-regulatory organization in connection with the sales, will equal our net proceeds for the sale of such shares of common stock.

Guggenheim Securities will provide written confirmation to us following the close of trading on The Nasdaq Global Select Market on each day in which shares of common stock are sold through it as sales agent under the sales agreement. Each confirmation will include the number of shares of common stock sold through it as sales agent on that day, the volume weighted average price of the shares of common stock sold, the percentage of the daily trading volume and the net proceeds to us.

Settlement for sales of shares of common stock will occur, unless the parties agree otherwise, on the second business day that is also a trading day following the date on which any sales were made in return for payment of the net proceeds to us. There is no arrangement for funds to be received in an escrow, trust or similar arrangement. We will report at least quarterly the number of shares of common stock sold through Guggenheim Securities under the sales agreement, the net proceeds to us and the compensation paid by us to Guggenheim Securities in connection with the sales of shares of common stock during the relevant period.

In connection with the sales of shares of common stock on our behalf, Guggenheim Securities will be deemed to be an “underwriter” within the meaning of the Securities Act, and the compensation paid to Guggenheim Securities will be deemed to be underwriting commissions or discounts. We have agreed in the sales agreement to provide indemnification and contribution to Guggenheim Securities against certain liabilities,

including liabilities under the Securities Act. As sales agent, Guggenheim Securities will not engage in any transactions that stabilize our common stock.

Our common stock is listed and traded on The Nasdaq Global Select Market under the symbol “COGT.” Computershare Trust Company, N.A. serves as the transfer agent and registrar for our common stock.

Guggenheim Securities and/or its affiliates have provided, and may in the future provide, various investment banking and other financial services for us for which services they have received, and may in the future receive, customary fees.

LEGAL MATTERS

Unless otherwise specified in this prospectus, the validity of the shares of common stock being offered hereby will be passed upon for us by Gibson, Dunn & Crutcher LLP, San Francisco, California. Certain legal matters will be passed upon for Guggenheim Securities by Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., Boston, Massachusetts.

EXPERTS

The financial statements incorporated in this prospectus supplement by reference to the Annual Report on Form 10-K for the year ended December 31, 2021 have been so incorporated in reliance on the report of PricewaterhouseCoopers LLP, an independent registered public accounting firm, given on the authority of said firm as experts in auditing and accounting.

WHERE YOU CAN FIND MORE INFORMATION

We file annual, quarterly and special reports, proxy statements and other information with the SEC, and we have filed with the SEC a registration statement on Form S-3 under the Securities Act of 1933 with respect to the securities offered by this prospectus. This prospectus, which forms part of the registration statement, does not contain all of the information included in the registration statement, including its exhibits and schedules. For further information about us and the securities described in this prospectus, you should refer to the registration statement, its exhibits and schedules and our reports, proxies, information statements and other information filed with the SEC.

Our filings are available to the public on the Internet, through a database maintained by the SEC at http://www.sec.gov. We also maintain a website at www.cogentbio.com. We have included our website address for the information of prospective investors and do not intend it to be an active link to our website. Information contained on our website does not constitute a part of this prospectus (or any document incorporated by reference herein).

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

The SEC allows us to incorporate by reference much of the information we file with the SEC, which means that we can disclose important information to you by referring you to those publicly available documents. The information that we incorporate by reference in this prospectus is considered to be part of this prospectus.

Because we are incorporating by reference future filings with the SEC, this prospectus is continually updated and those future filings may modify or supersede some of the information included or incorporated in this prospectus. This means that you must look at all of the SEC filings that we incorporate by reference to determine if any of the statements in this prospectus or in any document previously incorporated by reference have been modified or superseded. This prospectus incorporates by reference the documents listed below and any future filings we make with the SEC under Sections 13(a), 13(c), 14 or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”) (in each case, other than those documents or the portions of those documents not deemed to be filed) between the date of the initial registration statement and the effectiveness of the registration statement and following the effectiveness of the registration statement until the offering of the securities under the registration statement is terminated or completed, except that we are not incorporating by reference any information furnished (and not filed) with the SEC, including any information furnished pursuant to Items 2.02 or 7.01 of Form 8-K or related exhibits furnished pursuant to Item 9.01 of Form 8-K:

We also incorporate by reference into this prospectus all documents (other than current reports furnished under Item 2.02, Item 7.01 or Item 9.01 of Form 8-K and exhibits filed on such form that are related to such items) that are filed by us with the SEC pursuant to Sections 13(a), 13(c), 14 or 15(d) of the Exchange Act (i) after the date of the initial filing of the registration statement of which this prospectus forms a part and prior to effectiveness of the registration statement, and (ii) after the date of this prospectus but prior to the termination of the offering. These documents include, without limitation, Annual Reports on Form 10-K, Quarterly Reports on Form 10-Q, Current Reports on Form 8-K, as well as proxy statements.

You may request a copy of these filings, at no cost, by contacting us, either orally or in writing, at the following:

Cogent Biosciences, Inc.

200 Cambridge Park Drive, Suite 2500

Cambridge, Massachusetts 02140

(617) 945-5576

We maintain a website at www.cogentbio.com. Information about us, including our reports filed with the SEC, is available through that site. Such reports are accessible at no charge through our website and are made available as soon as reasonably practicable after such material is filed with or furnished to the SEC. Our website and the information contained on that website, or connected to that website, are not incorporated by reference in this prospectus supplement.

You may read and copy any materials we file with the SEC at the SEC’s website mentioned under the heading “Where You Can Find More Information.” The information on the SEC’s website is not incorporated by reference in this prospectus supplement.

Up to $75,000,000

Common Stock

PROSPECTUS SUPPLEMENT

Guggenheim Securities

        , 2022

Part II—INFORMATION NOT REQUIRED IN PROSPECTUS

Item 14. Other Expenses of Issuance and Distribution.Distribution

The following table sets forth the fees and expenses other than underwriting discounts and commissions, payable by us in connection with the registrationissuance and distribution of ourthe securities hereunder. All amountsbeing registered hereunder on Form S-3 (other than underwriting discounts and commissions, if any) are estimatesset forth below. Each item listed is estimated, except for the SEC registration fee and FINRA filing fee.

Item 15. Indemnification of Directors and Officers.Officers

Section 145 of the Delaware General Corporation Law (DGCL)(the “DGCL”) authorizes a corporation to indemnify its directors and officers against liabilities arising out of actions, suits and proceedings to which they are made or threatened to be made a party by reason of the fact that they have served or are currently serving as a director or officer to a corporation. The indemnity may cover expenses (including attorneys’ fees) judgments, fines, and amounts paid in settlement actually and reasonably incurred by the director or officer in connection with any such action, suit or proceeding. Section 145 permits corporations to pay expenses (including attorneys’ fees) incurred by directors and officers in advance of the final disposition of such action, suit or proceeding. In addition, Section 145 provides that a corporation has the power to purchase and maintain insurance on behalf of its directors and officers against any liability asserted against them and incurred by them in their capacity as a director or officer, or arising out of their status as such, whether or not the corporation would have the power to indemnify the director or officer against such liability under Section 145.

Provisions in our certificate of incorporation and amended and restated bylaws limit or eliminate the personal liability of our directors to the fullest extent permitted by the DGCL, as it now exists or may in the future be amended. Consequently, a director will not be personally liable to us or our stockholders for monetary damages or breach of fiduciary duty as a director, except for liability for:

These limitations of liability do not alter director liability under the federal securities laws and do not affect the availability of equitable remedies, such as an injunction or rescission.

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We have entered into indemnification agreements with each of our directors and executive officers. These agreements provide that we will indemnify each of our directors, executive officers and, at times, their affiliates to the fullest extent permitted by Delaware law. We will advance expenses, including attorneys’ fees (but excluding judgments, fines and settlement amounts), to each indemnified director, executive officer or affiliate in connection with any proceeding in which indemnification is available and we will indemnify our directors and officers for any action or proceeding arising out of that person’s services as a director or officer brought on behalf of us or in furtherance of our rights. Additionally, certain of our directors or officers may have certain rights to indemnification, advancement of expenses or insurance provided by their affiliates or other third parties, which indemnification relates to and might apply to the same proceedings arising out of such director’s or officer’s services as a director referenced herein. Nonetheless, we have agreed in the indemnification agreements that our obligations to those same directors or officers are primary and any obligation of such affiliates or other third parties to advance expenses or to provide indemnification for the expenses or liabilities incurred by those directors are secondary.

We also maintain general liability insurance which covers certain liabilities of our directors and officers arising out of claims based on acts or omissions in their capacities as directors or officers, including liabilities under the Securities Act.

Item 16. Exhibits and Financial Statement Schedules.

TheA list of exhibits to thefiled with this registration statement are listed inon Form S-3 is set forth on the Exhibit Index to this registration statement and areis incorporated herein by reference.

Item 17. Undertakings.Undertakings

The undersigned registrant hereby undertakes:

(a)(1) To file, during any period in which offers or sales are being made, a post-effective amendment to this registration statement:

(i) To include any prospectus required by Section 10(a)(3) of the Securities Act of 1933;1933, as amended (“Securities Act”);

(ii) To reflect in the prospectus any facts or events arising after the effective date of the registration statement (or the most recent post-effective amendment thereof) which, individually or in the aggregate, represent a fundamental change in the information set forth in the registration statement. Notwithstanding the foregoing, any increase or decrease in volume of securities offered (if the total dollar value of securities offered would not exceed that which was registered) and any deviation from the low or high end of the estimated maximum offering range may be reflected in the form of prospectus filed with the Securities and Exchange Commission pursuant to Rule 424(b) if, in the aggregate, the changes in volume and price represent no more than a 20 percent change in the maximum aggregate offering price set forth in the “Calculation of Registration Fee” table in the effective registration statement; and

(iii) To include any material information with respect to the plan of distribution not previously disclosed in the registration statement or any material change to such information in the registration statement;provided,

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(3) To remove from registration by means of a post-effective amendment any of the securities being registered which remain unsold at the termination of the offering;

(4) That, for the purpose of determining liability under the Securities Act of 1933 to any purchaser:

(i) Each prospectus filed by the registrant pursuant to Rule 424(b)(3) shall be deemed to be part of the registration statement as of the date the filed prospectus was deemed part of and included in the registration statement; and

(ii) Each prospectus required to be filed pursuant to Rule 424(b)(2), (b)(5), or (b)(7) as part of a registration statement in reliance on Rule 430B relating to an offering made pursuant to Rule 415(a)(l)(1)(i), (vii), or (x) for the purpose of providing the information required by Section 10(a) of the Securities Act of 1933 shall be deemed to be part of and included in the registration statement as of the earlier of the date such form of prospectus is first used after effectiveness or the date of the first contract of sale of securities in the offering described in the prospectus. As provided in Rule 430B, for liability purposes of the issuer and any person that is at that date an underwriter, such date shall be deemed to be a new effective date of the registration statement relating to the securities in the registration statement to which that prospectus relates, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof;provided, however,, that no statement made in a registration statement or prospectus that is part of the registration statement or made in a document incorporated or deemed incorporated by reference into the registration statement or prospectus that is part of the registration statement will, as to a purchaser with a time of contract of sale prior to such effective date, supersede or modify any statement that was made in the registration statement or prospectus that was part of the registration statement or made in any such document immediately prior to such effective date;

(5) That, for the purpose of determining liability of the registrant under the Securities Act of 1933 to any purchaser in the initial distribution of the securities, the undersigned registrant undertakes that in a primary offering of securities of the undersigned registrant pursuant to this registration statement, regardless of the underwriting method used to sell the securities to the purchaser, if the securities are offered or sold to such purchaser by means of any of the following communications, the undersigned registrant will be a seller to the purchaser and will be considered to offer or sell such securities to such purchaser:

(i) Any preliminary prospectus or prospectus of the undersigned registrant relating to the offering required to be filed pursuant to Rule 424;

(ii) Any free writing prospectus relating to the offering prepared by or on behalf of the undersigned registrant or used or referred to by the undersigned registrant;

(iii) The portion of any other free writing prospectus relating to the offering containing material information about the undersigned registrant or its securities provided by or on behalf of the undersigned registrant; and

(iv) Any other communication that is an offer in the offering made by the undersigned registrant to the purchaser;

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indemnification against such liabilities (other than the payment by the registrant of expenses incurred or paid by a director, officer or controlling person of the registrant in the successful defense of any action, suit or proceeding) is asserted by such director, officer or controlling person in connection with the securities being registered, the registrant will, unless in the opinion of its counsel the matter has been settled by controlling precedent, submit to a court of appropriate jurisdiction the question whether such indemnification by it is against public policy as expressed in the Securities Act of 1933 and will be governed by the final adjudication of such issue;issue.

(8) That, for purposes of determining any liability under the Securities Act of 1933, the information omitted from the form of prospectus filed as part of this registration statement in reliance upon Rule 430A and contained in a form of prospectus filed by the registrant pursuant to Rule 424(b)(1) or (4) or 497(h) under the Securities Act of 1933 shall be deemed to be part of this registration statement as of the time it was declared effective;

(9) That, for the purpose of determining any liability under the Securities Act, of 1933, each post-effective amendment that contains a form of prospectus shall be deemed to be a new registration statement relating to the securities offered therein, and the offering of such securities at that time shall be deemed to be the initialbona fide offering thereof; and

(10) To file an application for the purpose of determining the eligibility of the trustee to act under subsection (a) of Section 310 of the Trust Indenture Act of 1939 in accordance with the rules and regulations prescribed by the Securities and Exchange Commission under Section 305(b)(2) of the Trust Indenture Act of 1939.

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EXHIBIT INDEX

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POWER OF ATTORNEY AND SIGNATURES

Each person whose individual whose signature appears below hereby constitutesauthorizes and appoints each of Charles Wilson, Ph.D.Andrew Robbins and John Green as such person’s true andlawful attorney-in-fact and agent each of them, with full power of substitution and resubstitution for such personand full power to act without the other, as his or her true and lawful attorney-in-fact and agent to act in such person’shis or her name, place and stead and to execute in anythe name and all capacities,on behalf of each person, individually and in each capacity stated below, and to signfile any and all amendments (including post-effective amendments) to this Registration Statement, (orincluding any Registration Statement forand all post effective amendments and amendments thereto, and any registration statement relating to the same offering as this Registration Statement that is to be effective upon filing pursuant to Rule 462(b) under the Securities Act of 1933),1933, as amended, and to file the same, with all exhibits thereto, and allother documents in connection therewith, with the Securities and Exchange Commission, granting unto eachsaid attorney-in-factattorneys-in-fact and agent agents, and each of them, full power and authority to do and perform each and every act and thing, requisite and necessary to be done in and about the premises, as fully to all intents and purposes as such person might or could do in person, hereby ratifying and confirming all that anysaid attorney-in-factattorneys-in-fact and agent, agents or any of them or their or his substitute or substitutes of any of them, may lawfully do or cause to be done by virtue hereof.thereof.

Pursuant to the requirements of the Securities Act of 1933, as amended, this Registration Statement and Power of Attorney has been signed by the following person in the capacities and on the date indicated.

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