UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A INFORMATION

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

(Amendment No.         )

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

Check the appropriate box:

CALITHERA BIOSCIENCES, INC.

(Name of Registrant as Specified In Its Charter)

(Name of Person(s) Filing Proxy Statement if Other Than the Registrant)

Payment of Filing Fee (Check the appropriate box)

PRELIMINARY COPY—SUBJECT TO COMPLETION

CALITHERA BIOSCIENCES, INC.

343 Oyster Point Blvd., Suite 200

South San Francisco, California 94080

(650)870-1000

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held On June 9, 20201, 2022

Dear Stockholder:

You are cordially invited to attend the Annual Meeting of Stockholders of Calithera Biosciences, Inc., a Delaware corporation (the “Company”).corporation. The meeting will be held virtually, via live webcast athttps://web.lumiagm.com/282387153www.virtualshareholdermeeting.com/CALA2022 originating from South San Francisco, California on Tuesday,Wednesday, June 9, 20201, 2022 at 10:00 a.m. local time due to the emerging public health impact of the coronavirus outbreak(“COVID-19”) and to support the health and well-being of our partners, employees, and stockholders.time. You will not be able to attend the Annual Meeting in person. The meeting will be held for the following purposes, as more fully described in the accompanying proxy statement:

These items of business are more fully described in the Proxy Statementproxy statement accompanying this Notice.notice.

The record date for the Annual Meeting is April 13, 2020.4, 2022. Only stockholders of record at the close of business on thatthe record date may vote at the meeting or any adjournment thereof.

Important notice regarding the availability of proxy materials for the Annual Meeting of Stockholders to be held on June 9, 2020. 1, 2022. This notice, the proxy statement accompanying this notice and our Annual Report onForm 10-K may be found at http://ir.calithera.com/financial-information/annual-reports.

South San Francisco, California

April 21, 2020                , 2022

PRELIMINARY COPY—SUBJECT TO COMPLETION

CALITHERA BIOSCIENCES, INC.

343 Oyster Point Blvd., Suite 200

South San Francisco, California 94080

(650)870-1000

PROXY STATEMENT

FOR THE 20202022 ANNUAL MEETING OF STOCKHOLDERS

June 9, 20201, 2022

QUESTIONS AND ANSWERS ABOUT THESE PROXY MATERIALS AND VOTING

Why did I receive a notice regarding the availability of proxy materials on the internet?

Pursuant to rules adopted by the Securities and Exchange Commission, (the “SEC”),or the SEC, we have elected to provide access to our proxy materials over the internet. Accordingly, we have sent you a Notice of Internet Availability of Proxy Materials, (the “Notice”)or the Notice, because the Board of Directors, or the Board, of Calithera Biosciences, Inc. (sometimes referred to as the “Company” or “Calithera”), is soliciting your proxy to vote at the 20202022 Annual Meeting of Stockholders, (the “Annual Meeting”),or the Annual Meeting, including at any adjournments or postponements of the meeting.Annual Meeting. All stockholders will have the ability to access the proxy materials on the website referred to in the Notice or request to receive a printed set of the proxy materials. Instructions on how to access the proxy materials over the internet or to request a printed copy may be found in the Notice.

We expect to mail the Notice on or about April    30, 2020, 2022 to all stockholders of record entitled to vote at the Annual Meeting.

Will I receive any other proxy materials by mail?

No, you will not receive any other proxy materials by mail unless you request a paper copy of proxy materials. To request that a full set of the proxy materials be sent to your specified postal address, please goyou may (1) visit www.proxyvote.com, (2) call 1-800-579-1639, or (3) send an email to www.voteproxy.com or call 1-800-776-9962.sendmaterial@proxyvote.com. Please have your proxy card in hand when you access the website or call and follow the instructions provided.

How do I attend and participate in the Annual Meeting online?

This year’s Annual Meeting will be a completely virtual meeting of stockholders and will be webcast live over the Internet.internet. Any stockholder can attend the virtual meeting live online athttps://web.lumiagm.com/282387153www.virtualshareholdermeeting.com/CALA2022. The webcast will start at 10 a.m. Pacific Time. Stockholders as of April 4, 2022, the Record Daterecord date, may vote and submit questions while attending the meeting online. We encourage you to access the meeting prior to the start time. If you encounter any difficulties accessing the virtual meeting during the check-in or meeting time, please refer toa call center support number will be provided on the technical support information locatedmeeting login page athttps://go.lumiglobal.com/faqwww.virtualshareholdermeeting.com/CALA2022. at 9:45 a.m. Pacific Time. In order to enter the meeting,Annual Meeting, you will need the control number and the password: cala2020.number. The control number will be included in the Noticenotice or on your proxy card if you are a stockholder of record of shares of common stock (as defined below). If your shares are held in “street name” through a broker, bank or other nominee, in order to participate in the virtual annual meeting, you must first obtain a legal proxy from your broker, bank or other nominee reflecting the number of shares of CALACalithera held as of the record date, your name and email address. You must then submit a request for registration to American Stock Transfer & Trust Company, LLC: (1) by email toproxy@astfinancial.com; (2) by facsimile to 718-765-8730; or (3) by mail to American Stock Transfer & Trust Company, LLC, Attn: Proxy Tabulation Department, 6201 15th Avenue, Brooklyn, NY 11219. Requests for registration must be labeled as “Legal Proxy” and be received by American Stock Transfer & Trust Company, LLC no later than 5:00 p.m. Eastern time on June 2, 2020.May 23, 2022. Instructions on how to attend and participate online are available athttps://web.lumiagm.com/282387153www.virtualshareholdermeeting.com/CALA2022. You will not be able to attend the Annual Meeting in person.

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Why a Virtual-Only Online Meeting?

Conducting the annual meetingAnnual Meeting virtually allows for remote participation in light of the spread of the coronavirus disease(COVID-19) and increases the opportunity for all stockholders to participate and communicate their views to a much wider audience. In addition, holding the meetingAnnual Meeting virtually allows us to make much more efficient use of the time of our independent directors. Stockholder rights are not affected. Additionally, we use software that verifies the identity of each participating stockholder and ensures during the question and answer portion of the meeting that they are granted the same rights they would have at anin-person meeting. We may consider a change in our virtual-only meeting practice in the future. Given the above listed factors, we feel a virtual-only meeting is the right choice for Calithera and its stockholders at this time.

Our virtual Annual Meeting allows stockholders to submit questions and comments before and during the Annual Meeting. To the extent time doesn’t allow us to answer all of the appropriately submitted questions, we will answer them in writing on our investor relations website, athttp://ir.calithera.com/investor-overview, soon after the meeting. If we receive substantially similar questions, we will group such questions together and provide a single response to avoid repetition.

What happens if there are technical difficulties during the Annual Meeting?

We will have technicians ready to assist you with any technical difficulties you may have accessing the virtual Annual Meeting, voting at the Annual Meeting or submitting questions at the Annual Meeting. If you encounter any difficulties accessing the virtual Annual Meeting during thecheck-in or meeting time, please refer toa call center support number will be provided on the technical support information locatedmeeting login page athttps://go.lumiglobal.com/faqwww.virtualshareholdermeeting.com/CALA2022. at 9:45 a.m. Pacific Time.

If we experience technical difficulties at the Annual Meeting and are not able to resolve them within a reasonable amount of time, we will adjourn the Annual Meeting to a later date and will provide notice of the date and time of such adjourned meeting athttps:http://ir.calithera.com/financial-information/annual-reports and on a Current Report on Form8-K that we will file with the SEC. For additional information on how you can attend any postponement or adjournment of the Annual Meeting, see “What happens if the Annual Meeting is postponed or adjourned” below.

Who can vote at the Annual Meeting?

Only stockholders of record at the close of business on April 13, 20204, 2022 will be entitled to vote at the Annual Meeting. On thisthe record date, there were 64,692,68397,236,174 shares of common stock outstanding and 14,817,484 shares of Series A preferred stock (on an as-converted to common stock basis) entitled to vote.vote at the Annual Meeting.

Stockholder of Record: Shares of Common Stock Registered in Your Name

If on April 13, 20204, 2022, your shares of common stock were registered directly in your name with Calithera’sour transfer agent, American Stock Transfer & Trust Company, LLC, then you are a stockholder of record. As a stockholder of record, you may vote online at the virtual Annual Meeting or vote by proxy. Whether or not you plan to attend the virtual Annual Meeting, we urge you to fill out and return the enclosed proxy card to ensure your vote is counted.

Beneficial Owner: Shares of Common Stock Registered in the Name of a Broker or Bank

If on April 13, 2020your4, 2022,your shares of common stock were held, not in your name, but rather in an account at a brokerage firm, bank, dealer or other similar organization, then you are the beneficial owner of shares held in “street name” and the Notice isbeingisbeing forwarded to you by that organization. The organization holding your account is considered to be the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to direct your broker or other agent regarding how to vote the shares in your account. You are also invited to attend the Annual Meeting. However, since you are not the stockholder of record, you may not vote your shares online at the virtual meeting unless you request and obtain a valid proxy from your broker or other agent.

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Stockholder of Record: Shares of Series A Preferred Stock in Your Name

Our existing Certificate of Designations provides that the holder of our Series A preferred stock shall vote together with the holders of the common stock as a single class. The number of votes that the holder of the Series A preferred stock is entitled to cast is based on the number of shares of common stock that the shares of Series A preferred stock are convertible into, subject to the “Share Cap” described in our Certificate of Designations. The Share Cap is defined to mean shares of common stock equal to 14,817,484 (or (i) 0.1999 multiplied by (ii) 74,124,484). As of the record date all the shares of Series A preferred stock are held by Millennium Pharmaceuticals, Inc.

What am I voting on?

There are fourfive matters scheduled for a vote:

What if another matter is properly brought before the meeting?

The Board knows of no other matters that will be presented for consideration at the Annual Meeting. If any other matters are properly brought before the meeting, it is the intention of the persons named in the accompanying proxy to vote on those matters in accordance with their best judgment.

How do I vote?

You may either vote “For” the nominees to the Board or you may “Withhold” your vote for any nominee you specify. With regard to your advisory vote on how frequently we should solicit stockholder advisory approval of our Named Executive Officer compensation, you may vote for any one of the following: “One Year,” “Two Years,” or “Three Years,” or you may abstain from voting on that matter. For each of the other matters to be voted on, you may vote “For,” “Against” or abstain from voting.

The procedures for voting are fairly simple:

Stockholder of Record: Shares Registered in Your Name

If you are a stockholder of record, you may vote online during the Annual Meeting, vote by proxy or vote by proxy through the internet or vote by proxy using a proxy card that you may request or that we may elect to deliver at a later time. Whether or not you plan to attend the meeting, we urge you to vote by proxy to ensure your vote is counted. You may still attend the meeting online and vote during the meeting even if you have already voted by proxy.

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Beneficial Owner: Shares Registered in the Name of Broker or Bank

If you are a beneficial owner of shares registered in the name of your broker, bank, or other agent, you should have received aNoticeaNotice containing voting instructionsfrominstructionsfrom that organization rather than from Calithera. Simply follow the voting instructions in the NoticetoNoticeto ensure that your vote is counted. To vote online during the Annual Meeting, you must obtain a valid proxy from your broker, bank or other agent. Follow the instructions from your broker or bank included with these proxy materials, or contact your broker or bank to request a proxy form.

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What if I return a proxy card or otherwise vote but do not make specific choices?

If you are a stockholder of record and return a signed and dated proxy card or otherwise vote without marking voting selections, your shares will be voted, as applicable, “For”applicable:

If any other matter is properly presented at the meeting, your proxyholder (one of the individuals named on your proxy card) will vote your shares using his or her best judgment.

Who is paying for this proxy solicitation?

We will pay for the entire cost of soliciting proxies. In addition to these proxy materials, our directors and employees may also solicit proxies in person, or by other means of communication. Directors and employees will not be paid any additional compensation for soliciting proxies. We may also reimburse brokerage firms, banks and other agents for the cost of forwarding proxy materials to beneficial owners.

What does it mean if I receive more than one Notice?

If you receive more than one Notice,notice, your shares may be registered in more than one name or in different accounts. Please follow the voting instructions on the Noticesnotices to ensure that all of your shares are voted.

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Secretary, c/o Calithera Biosciences, Inc., 343 Oyster Point Blvd., Suite 200, South San Francisco, CA 9408094080; provided, however, that if our 20212023 Annual Meeting of stockholders is held before May 9, 2021,2, 2023, or after July 9, 2021,1, 2023, then the reasonable amount of time prior to the date we begin to print and mail our proxy statement for the 20212023 Annual Meeting of stockholders. If you wish to submit a proposal (including a director nomination) at the meeting that is not to be included in next year’s proxy materials, you must provide specified information in writing to our corporate Secretary at the address above no earlier than the close of business on February 8, 2021,1, 2023, and no later than the close of business on March 10, 2021,3, 2023, except that if our 20212023 Annual Meeting of stockholders is held more than 30 days before or after June 9, 2021,1, 2023, notice by the stockholder to be timely may be received no earlier than the close of business on the 120^th day prior to the 20212023 Annual Meeting of stockholders and no later than the close of business on the later of (i) the 90^th day before the 20212023 Annual Meeting of stockholders or (ii) tenth day following the day on which public announcement of the date of the 20212023 Annual Meeting is made. If such proposal is submitted after March 10, 2021,3, 2023, it will be considered untimely. You are also advised to review our Amended and Restated Bylaws, (the “Bylaws”),or the Bylaws, which contain a description of the information required to be submitted as well as additional requirements about advance notice of stockholder proposals and director nominations.

How are votes counted?

Votes will be counted by the inspector of election appointed for the meeting,Annual Meeting, who will separately count, (a) for the proposal to elect directors, votes “For,” “Withhold” and brokernon-votes, and (b) with respect to other proposals, votes “For” and “Against,” abstentions and, if applicable, brokernon-votes.

Abstentions will be counted towards the vote total for Proposal No.proposals 2, 3, 4 and 3,5 and will have the same effect as “Against” votes. For Proposal No. 4, in the event that no frequency receives a majority of the votes, the Company will consider the frequency that receives the most votes cast to be the frequency preferred by our stockholders. Brokernon-votes on Proposalsproposals 1, 3 and 45 will have no effect and will not be counted towards the vote total for any of these proposals.

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What is the quorum requirement?

A quorum of stockholders is necessary to hold a valid meeting. A quorum will be present if stockholdersholdingatstockholdersholdingat least a majority of the outstanding shares entitled to vote are present at the virtual meeting or represented by proxy. On the record date, there were 64,692,68397,236,174 outstanding shares outstandingof common stock and shares of Series A preferred stock equivalent to 14,817,484 shares of common stock entitled to vote. Thus, the holders of 32,346,34256,026,829 shares must be present in person or represented by proxy at the meetingAnnual Meeting to have a quorum.

Your shares will be counted towards the quorum only if you submit a valid proxy (or one is submitted on your behalf by your broker, bank or other nominee) or if you vote online during the virtual meeting. Abstentions and brokernon-votes will be counted towards the quorum requirement. If there is no quorum, the holders of a majority of shares present online during the virtual meeting or represented by proxy may adjourn the meeting to another date.

What happens if the Annual Meeting is postponed or adjourned?

Your proxy may be voted at the postponed or adjourned Annual Meeting. You will still be able to change your proxy until it is voted.

Any adjournment of the Annual Meeting can be accessed at the same website listed above and you may vote at any postponement or adjournment using the control number.

How can I find out the results of the voting at the Annual Meeting?

Preliminary voting results will be announced at the Annual Meeting. In addition, final voting results will be published in a current report on Form8-K that we expect to file within four business days after the Annual Meeting. If final voting results are not available to us in time to file aForm 8-K within four business days after the meeting, we intend to file aForm 8-K to publish preliminary results and, within four business days after the final results are known to us, file an additionalForm 8-K to publish the final results.

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PROPOSAL NO. 1

ELECTIONOF DIRECTORS

Calithera’sOur Board is divided into three classes. Each class consists, as nearly as possible, ofone-third of the total number of directors, and each class has a three-year term. Vacancies on the Board may be filled only by persons elected by a majority of the remaining directors. A director elected by the Board to fill a vacancy in a class, including vacancies created by an increase in the number of directors, shall serve for the remainder of the full term of that class and until the director’s successor is duly elected and qualified.

The Board presently has eightnine members. There are three directors in the class whose term of office expires in 2020, Susan Molineaux,2022, Jonathan G. Drachman, M.D., Suzy Jones, and Deepa Pakianathan, Ph.D., Blake Wise Dr. Drachman, Ms. Jones, and H. Ward Wolff. Dr. Molineaux and Messrs. Wise and WolffPakianathan have each served as members of our Board since June 2010,December 2013, August 2016, and September 2017 and December 2014,2012, respectively. Dr. Drachman is not standing for reelection to the Board when his term expires at the Annual Meeting. The nominees listed below are currentlycurrent directors of the Company.Ifand if elected at the Annual Meeting, these nominees would serve until the 20232025 Annual Meeting and until a successor has been duly elected and qualified, or, if sooner, until the director’s death, resignation or removal. Our policy is to encourage directors and nominees for director to attend the Annual Meeting. SevenEight out of nine of the directors attended the 20192021 Annual Meeting, of Shareholders, with six participating via remote communication.which was held virtually.

Directors are elected by a plurality of the votes of the holders of shares present online during the virtual meeting or represented by proxy and entitled to vote on the election of directors. Accordingly, the nominee receiving the highest number of affirmative votes will be elected.Shareselected. Shares represented by executed proxies will be voted, if authority to do so is not withheld, for the election of the nominee named below. If the nominee becomes unavailable for election as a result of an unexpected occurrence, shares that would have been voted for that nominee will instead be voted for the election of a substitute nominee proposed by Calithera.us. Each person nominated for election has agreed to serve if elected. The Company’sOur management has no reason to believe that any nominee will be unable to serve.

The following is a brief biography of the nominees and the directors whose term will continue after the Annual Meeting.

NOMINEESFOR ELECTIONFORA THREE-YEAR TERM EXPIRINGATTHE 2025 ANNUAL MEETING

Deepa R. Pakianathan, Ph.D.Dr. Pakianathan, age 57, is our lead independent director and has served as a member of our board of directors since September 2012. Dr. Pakianathan currently serves as Chief Executive Officer of Redd Pharmaceuticals, Inc., a private biotechnology company. Since 2001, Dr. Pakianathan has served as a Managing Member at Delphi Ventures, a venture capital firm. From 2007 to 2019, Dr. Pakianathan served on the board of directors of Alder Pharmaceuticals, Inc., from 2008 to 2019, Oncomed Pharmaceuticals, Inc., and from 2020 to 2021, FS Development Corp. and since 2021 FS Development Corp II. From 1998 to 2001, Dr. Pakianathan served as a Vice President in the healthcare group at JP Morgan Chase & Company. From 1993 to 1997, Dr. Pakianathan served as a postdoctoral scientist in the Immunology Department at Genentech, Inc. Dr. Pakianathan currently serves on the board of directors of Theravance Biopharma, Inc., Karyopharm Therapeutics, Inc., and Mereo BioPharma Group plc. Dr. Pakianathan holds an M.S. and a Ph.D. from Wake Forest University, a B.Sc. from the University of Bombay, India and an M.Sc. from The Cancer Research Institute at the University of Bombay, India.

We believe Dr. Pakianathan’s experience as a venture capital investor in and as a director for multiple biotechnology companies, as well as her experience as a biotechnology investment banker, qualify her to serve on our board of directors.

Suzy Jones. Ms. Jones, age 56, has served as a member of our board of directors since August 2016. Since September 2010, Ms. Jones has been the Founder and Managing Partner of DNA Ink, a boutique life sciences

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advisory firm. Prior to founding DNA Ink, Ms. Jones spent 20 years at Genentech, Inc. in various roles in immunology research, product development managing cross functional teams for Rituxan and Avastin, and business development where she was Head of Non-Oncology Licensing and later Interim Head of Partnering and Head of Business Development. Ms. Jones serves as a member of the board of directors of Patrys Limited, an ASX listed Australian biotechnology company. She received a B.S. degree in Biology from University of California, Santa Cruz.

We believe Ms. Jones’s experience in the biotechnology industry qualifies her to serve on our board of directors.

THE BOARD RECOMMENDS

A VOTEIN FAVOROFTHE NAMED NOMINEES.

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DIRECTORS CONTINUINGIN OFFICE UNTILTHE2023 ANNUAL MEETING

Susan M. Molineaux, Ph.D. Dr. Molineaux, age 66,68, has served as our President, Chief Executive Officer and as a member of our board of directors since sheco-founded Calithera in March 2010. Dr. Molineauxco-founded Proteolix, Inc., a biopharmaceutical company, where she served as Chief Scientific Officer from 2003 to 2005, Chief Executive Officer from January 2006 to January 2009 and again as Chief Scientific Officer from February 2009 until Proteolix’s acquisition by Onyx Pharmaceuticals, Inc. in November 2009. From 2000 to 2003, Dr. Molineaux served as Vice President of Biology at Rigel Pharmaceuticals, Inc., a drug development company. From 1999 to 2000, she served as Vice President of Biology at Praelux, Inc., a biopharmaceutical company, and from 1994 through 1999, she served as Vice President of Drug Development at Praecis Pharmaceuticals, Inc., a biopharmaceutical company. From 1989 until 1994, she was a scientist in the Immunology group at Merck & Co. Dr. Molineaux currently serves as a member of the board of directors of Geron Corporation, Theravance Biopharma, Inc., Cyteir Therapeutics, Inc. and Smith College, and is a Scientific Advisor for Lightstone Ventures. Dr. Molineaux holds a B.S. in Biology from Smith College and a Ph.D. in Molecular Biology from Johns Hopkins University, and completed a postdoctoral fellowship at Columbia University.

We believe Dr. Molineaux’s experience on our board of directors and as our Chief Executive Officer, as well as her experience in our industry qualifies her to serve on our board of directors.

Blake Wise.Mr. Wise, age 49,51, has served as a member of our board of directors since September 2017. Since December 2019, Mr. Wise has served as Chief Executive Officer and a member of the board of directors of

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We believe Mr. Wolff’s extensive financial experience and experience in the biotechnology industry qualifies him to serve on our board of directors.

THE BOARD RECOMMENDS

A VOTEIN FAVOROFTHE NAMED NOMINEES.

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Combinations Development Performance Unit at GlaxoSmithKline plc, or GSK, where he oversaw the University of Washington in Seattle,clinical activities on multiple early-stage clinical trials with targeted agents and asnovel immune-based therapies. Prior to GSK, Dr. Orford was at Merck & Co., Inc., where he worked on early clinical development programs across oncology and other therapeutic areas. Previously, Dr. Orford was a Senior Investigator in the Division of Research Fellow and EducationInstructor at the Puget Sound Blood Center. Dr. Drachman currently serves on the board of directors of Harpoon Therapeutics. Dr. Drachman received a B.A. in Biochemistry from Harvard UniversityMassachusetts General Hospital and an M.D. from Harvard Medical School. HeSchool where he completed his residencyclinical training in Internal Medicine as well as postdoctoral work studying the epigenetic regulation of hematopoietic and fellowship in Medical Oncology at the University of Washington.

We believeembryonic stem cell differentiation. Dr. Drachman’s experience in the biotechnology industry qualifies him to serve on our board of directors.

Suzy Jones. Ms. Jones, age 54, has served as a member of our board of directors since August 2016. Since September 2010, Ms. Jones has been the FounderOrford received his undergraduate, M.D. and Managing Partner of DNA Ink, a boutique life sciences advisory firm. Prior to founding DNA Ink, Ms. Jones spent 20 years at Genentech in various roles in immunology research, product development managing cross functional teams for Rituxan and Avastin, and business development where she was Head ofNon-Oncology Licensing and later Interim Head of Partnering and Head of Business Development. In 2010, she was named by Black Health Magazine as one of the, “Top 25 Most Influential African Americans in Healthcare, Medicine, Pharmaceutical and Food Industries.” Ms. Jones serves as a member of the board of directors of Patrys Limited, an ASX listed Australian biotechnology company. She received a B.S. degree in BiologyPh.D. degrees from University of California, Santa Cruz.

We believe Ms. Jones’s experience in the biotechnology industry qualifies her to serve on our board of directors.Georgetown University.

INFORMATION REGARDING THE BOARD OF DIRECTORS AND CORPORATE GOVERNANCE

BOARD DIVERSITY

While we value diversity, our Nominating and Corporate Governance Committee does not have a formal written policy with regard to the consideration of diversity in identifying director nominees. However, diversity of experience is one of the numerous criteria our Nominating and Corporate Governance Committee reviews before recommending a candidate. Our Nominating and Corporate Governance Committee believes diversity of experience can come from personal characteristics such as race and gender as well as diversity in background, viewpoints and skills. Our Nominating and Corporate Governance Committee and our board of directors is committed to actively seeking highly qualified women and individuals from underrepresented groups to include in the pool from which new candidates are selected.

While our Nominating and Corporate Governance Committee is committed to continued focus on and expansion of our board’s diversity, we also believe our current board represents a diversity of expertise, talents, skills, backgrounds, and personal characteristics. Of the nine directors on our board, three are women. Furthermore, our board members range in age from 50 to 73. Our board of directors also seeks members that have extensive leadership experience, but may seek other members with different backgrounds, based upon the contributions they can make to Calithera. Currently, our directors all have significant leadership experience and collectively bring expertise and experience in finance, research and development, healthcare, corporate strategy, public company governance, regulatory, drug development and commercialization of pharmaceutical products.

INDEPENDENCEOF THE BOARD

As required under the Nasdaq Stock Market (“Nasdaq”)listing standards, a majority of the members of a listed company’s board of directors must qualify as “independent,” as affirmatively determined by the Board. The Board consults with the Company’sour counsel to ensure that the Board’s determinations are consistent with relevant securities and other laws and regulations regarding the definition of “independent,” including those set forth in pertinent listing standards of Nasdaq, as in effect from time to time.

Consistent with these considerations, after review of all relevant identified transactions or relationships between each director, or any of his or her family members, and Calithera, our senior management and our independent auditors, the Board has affirmatively determined that the following seven directors are independent directors within the meaning of the applicable NasdaqlistingNasdaqlisting standards: Drs. Agarwal, Drachman and Pakianathan, Mses. George andMs. Jones and Mr.Messrs. Garland, Wise and Wolff. In making this determination, the Board found that none of these directors or nominees for director had a material or other disqualifying relationship with Calithera.

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ROLEOFTHE BOARDIN RISK OVERSIGHT

TheOur Board has an active role, as a whole and also at the committee level, in overseeing management of Company’sour risks. Our Board has received regular updates from the management team on the evolving novel coronavirus (COVID-19) situationCOVID-19 pandemic and is involved in strategy decisions related to the impact of the novel coronavirus (COVID-19)COVID-19 pandemic on our business. The Board regularly reviews information regarding our credit, liquidity and operations, as well as the risks associated with each. The Audit Committee’s charter mandates the Audit Committee to review and discuss with management, and our independent registered public accounting firm, as appropriate, Company’sour major financial risk exposures and the steps taken by management to monitor and control these exposures. The Compensation Committee of the Board, (the “Compensation Committee”)or the Compensation Committee, is responsible for overseeing the management of risks relating to Company’sour executive compensation plans and arrangements. The Nominating and Corporate Governance Committee manages risks associated with the independence of the Board and potential conflicts of interest. While each committee is responsible for evaluating certain risks and overseeing the management of such risks, the entire Board is regularly informed through committee reports about such risks.

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Audit Committee

Our Audit Committee consists of Mr. Wolff, Ms. Jones and Mr. Wise.TheMessrs. Garland, Wise and Wolff.The Audit Committee met fourtimesfivetimes during 2019. The2021. Our Board has adopted a written Audit Committee charter that is available to stockholdersonstockholderson the Investors section of our website at www.calithera.com.

TheOur Board reviews the Nasdaq listing standards definition of independence for Audit Committee members on an annual basis and has determined that all members of the Audit Committee are independent (as independence is currently defined in Rule 5605(c)(2)(A)(i) and (ii) of the Nasdaq listing standards).

TheOur Board has also determined that Mr. Wolff qualifies as an “audit committee financial expert,” as defined in applicable SEC rules.Therules.Our Board made a qualitative assessment of Mr. Wolff’s level of knowledge and experience based on a number of factors, including his formal education and experience as a chief financial officer for public reporting companies.

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The primary purpose of the Compensation Committee is to discharge the responsibilities of the Board to oversee our compensation policies, plans and programs and to review and determine the compensation to be paid to our executive officers, directors and other senior management, as appropriate. Specific responsibilities of the Compensation Committee include:

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As part of its engagement, Arnosti Consultingthe Compensation Consultant was requested by the Compensation Committee to develop a comparative group of companies and to perform analyses of competitive performance and compensation levels for that group. At the request of management, Arnosti Consultingthe Compensation Consultant also conducted individual interviews with members of the Compensation Committee and senior management to learn more about the Company’sour business operations and strategy, key performance metrics and strategic goals, as well as the labor markets in which the Company competes.Arnosti Consultingwe compete.The Compensation Consultant ultimately developed recommendations that were presented to the Compensation Committee for its consideration. Following an active dialogue with Arnosti Consultingthe Compensation Consultant, the Compensation Committee approved the recommendations.

Under its charter, the Compensation Committee may form, and delegate authority to, subcommittees as appropriate. The Compensation Committee has delegated authority to Dr. Susan Molineaux, to which it delegated authority to grant, without any further action required by the Compensation Committee, stock optionsequity grants to employees who are not officers of the Company.Calithera. The purpose of this delegation of authority is to enhance the flexibility of option administration within the CompanyCalithera and to facilitate the timely grant of optionsequity tonon-management employees, particularly new employees, within specified limits approved by the Compensation Committee or our Board.

The Compensation Committee has made most of the significant adjustments to annual compensation, determined bonus and equity awards and established new performance objectives at one or more meetings held during the first quarter of the year. However, the Compensation Committee also considers matters related to individual compensation, such as compensation for new executive hires, as well as high-level strategic issues, such as the efficacy of the Company’sour compensation strategy, potential modifications to that strategy and new trends, plans or approaches to compensation, at various meetings throughout the year. Generally, the Compensation Committee’s

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The Nominating and Corporate Governance Committee believes that candidates for director should have certain minimum qualifications, including the ability to read and understand basic financial statements, being over 21 years of age and having the highest personal integrity and ethics. The Nominating and Corporate Governance Committee also intends to consider such factors as possessing relevant expertise upon which to be able to offer advice and guidance to management, having sufficient time to devote to the affairs of the Company, demonstrated excellence in his or her field, having the ability to exercise sound business judgment, and having the commitment to rigorously represent the long-term interests of our stockholders, diversity of experience and such other factors as the Company’s stockholders.Nominating and Corporate Governance Committee may deem appropriate. However, the Nominating and Corporate Governance Committee retains the right to modify these qualifications from time to time. Candidates for director nominees are reviewed in the context of the current composition of the Board, theour operating requirements of the Company and the long-term interests of our stockholders. In conducting this assessment, the Nominating and Corporate Governance Committee typically considers diversity, age, skills and such other factors as it deems appropriate, given the current needs of the Board and the Company,Calithera, to maintain a balance of knowledge, experience and capability.

In the case of incumbent directors whose terms of office are set to expire, the Nominating and Corporate Governance Committee reviews these directors’ overall service to the Company during their terms, including the number of meetings attended, level of participation, quality of performance and any other relationships and transactions that might impair the directors’ independence. The Committee also takes into account the results of the Board’s self-evaluation, conducted annually on a group and individual basis. In the case of new director

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STOCKHOLDER COMMUNICATIONS WITHTHE BOARD OF DIRECTORS

Historically, we have not provided a formal process related to stockholder communications with the Board. Nevertheless, every effort has been made to ensure that the views of stockholders are heard by the Board or individual directors, as applicable, and that appropriate responses are provided to stockholders in a timely manner. We believe our responsiveness to stockholder communications to the Board has been excellent.

CODEOF ETHICS

We have adopted the CalitheraCodeCalitheraCode of Business Conduct and Ethics that applies to all officers, directors and employees. The Code of Business Conduct and Ethics is available on the Investors section of our website at www.calithera.com.Ifwww.calithera.com.If we make any substantive amendments to the Code of Business Conduct and Ethics or grants any waiver from a provision of the Code to any executive officer or director, we will promptly disclose the nature of the amendment or waiver on our website.

CORPORATE GOVERNANCE GUIDELINES

The Board has documented our governance practices by adopting Corporate Governance Guidelines to assure that the Board will have the necessary authority and practices in place to review and evaluate our business operations as needed and to make decisions that are independent of our management. The guidelines are also intended to align the interests of directors and management with those of our stockholders. The Corporate Governance Guidelines set forth the practices the Board intends to follow with respect to board composition and selection, board meetings and involvement of senior management, Chief Executive Officer performance evaluation and succession planning, and board committees and compensation. The Corporate Governance Guidelines, as well as the charters for each committee of the Board, may be viewed on the Investors section of our website at www.calithera.com.

ANTI-HEDGING POLICY

Our insider trading policy prohibits the trading of derivatives or pledges or hedging of our equity securities by members of our board of directors, executive officers, employees and consultants.

1619

PROPOSAL NO. 2

RATIFICATIONOF SELECTIONOF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

The Audit Committee has selected Ernst & Young LLP as our independent registered public accounting firm for the year ending December 31, 20202022 and has further directed that management submit the selection of its independent registered public accounting firm for ratification by the stockholders at the Annual Meeting. Ernst & Young LLP was engaged in 2014 and has audited our financial statements since 2010. Representatives ofErnstofErnst & Young LLP are expected to be present at the Annual Meeting. They will have an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

Neither our Bylaws nor other governing documents or law require stockholder ratification of the selection of Ernst & Young LLP as our independent registered public accounting firm. However, the Audit Committee is submitting the selection of Ernst & Young LLP to the stockholders for ratification as a matter of good corporate practice. If the stockholders fail to ratify the selection, the Audit Committee will reconsider whether or not to retain that firm. Even if the selection is ratified, the Audit Committee in its discretion may direct the appointment of different independent auditors at any time during the year if they determine that such a change would be in the best interests of the CompanyCalithera and itsour stockholders.

The affirmative vote of the holders of a majority of the shares present online during the virtual meeting or represented by proxy and entitled to vote on the matter at the Annual Meeting will be required to ratify the selection of Ernst & Young LLP.

PRINCIPAL ACCOUNTANT FEESAND SERVICES

The following table represents aggregate fees billed to Calithera for the years ended December 31, 20192021 and 2018,2020, by Ernst & Young LLP, our independent registered accounting firm.

All fees incurred were pre-approved by our Audit Committee.

PRE-APPROVAL POLICIESAND PROCEDURES.

The Audit Committee has adopted a policy and procedures for thepre-approval of audit andnon-audit services rendered by the Company’sour independent registered public accounting firm, Ernst & Young LLP. The policy generallypre-approves specified services in the defined categories of audit services, audit-related services and tax services up to specified amounts.Pre-approval may also be given as part of the Audit Committee’s approval of the scope of the engagement of the independent auditor or on an individual, explicit,case-by-case basis before

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The Audit Committee has determined that the rendering of services other than audit services by Ernst & Young LLP is compatible with maintaining the principal accountant’s independence.

THE BOARD RECOMMENDS

A VOTEIN FAVOROF PROPOSAL NO. 2.

1821

PROPOSAL NO. 3

ADVISORY VOTEON EXECUTIVE COMPENSATION

Under the Dodd-Frank Wall Street Reform and Consumer Protection Act and Section 14A of the Securities Exchange Act the Company’sof 1934, our stockholders are entitled to vote to approve, on an advisory basis, the compensation of the Company’sour named executive officers as disclosed in this proxy statement in accordance with SEC rules.

This vote is not intended to address any specific item of compensation, but rather the overall compensation of the Company’sour named executive officers and the philosophy, policies and practices described in this proxy statement. The compensation of the Company’sour named executive officers subject to the vote is disclosed in the compensation tables and the related narrative disclosure contained in this proxy statement. As discussed in those disclosures, the Company believeswe believe that itsour compensation policies and decisions are designed to meet two objectives: (i) to attract and retain talented and skilled executives by paying for performance and (ii) to align compensation of our executives with our stockholders through an appropriate mix of short-term and long-term compensation. Compensation of the Company’sour named executive officers is designed to enable the Companyus to attract and retain talented and experienced executives to lead the Companyus successfully in a competitive environment.

Accordingly, the Board is asking the stockholders to indicate their support for the compensation of the Company’sour named executive officers as described in this proxy statement by castinga non-binding advisory vote “FOR” the following resolution:

“RESOLVED, that the compensation paid to the Company’s named executive officers, as disclosed pursuant to Item 402 ofRegulation S-K, including the compensation tables and narrative discussion that accompanies the compensation tables, is hereby APPROVED.”

Because the vote is advisory, it is not binding on the Board or the Company.Calithera. Nevertheless, the views expressed by the stockholders, whether through this vote or otherwise, are important to the Board and the Compensation Committee, and accordingly the Board and the Compensation Committee intend to consider the results of this vote in making determinations in the future regarding executive compensation arrangements.

Advisory approval of this proposal requires the vote of the holders of a majority of the shares present online during the virtual meeting or represented by proxy and entitled to vote on the matter at the annual meeting.Annual Meeting. Unless the Board decides to modify its policy regarding the frequency of soliciting advisory votes on the compensation of the Company’sour named executives, the nextscheduled say-on-pay vote will be at the 20212023 Annual Meeting of Stockholders.

THE BOARD RECOMMENDS

A VOTEIN FAVOROF PROPOSAL NO. 3.

1922

PROPOSAL NO. 4

ADVISORY VOTEON THE FREQUENCYPPROVALOF

S ATOCKHOLDERMENDMENTTOOUR ACDVISORYERTIFICATEOF VIOTESNCORPORATIONONTO EXECUTIVEFFECTA REVERSE STOCK SPLITOFTHE ISSUEDAND OUTSTANDING COMPENSATIONOMMON STOCK

The Dodd-Frank Wall Street ReformOur Board has approved, and Consumer Protection Act and Section 14Ais recommending that our stockholders approve, a proposed amendment to our certificate of incorporation, to effect a reverse split of the issued and outstanding shares of the common stock at a ratio of between one-for-ten and one-for-twenty, with such ratio to be determined at the sole discretion of our Board, or the Reverse Stock Split.The form of proposed amendment to our certificate of incorporation to effect the Reverse Stock Split is attached as Appendix A to this proxy statement. The text of the proposed amendment is subject to revision to include such changes as may be required by the Secretary of State of the State of Delaware and as our Board deems necessary or advisable to effect the proposed amendment of the certificate of incorporation. If a certificate of amendment is filed with the Secretary of State of the State of Delaware, the certificate of amendment to the certificate of incorporation will effect the Reverse Stock Split by reducing the outstanding number of shares of the common stock by the ratio to be determined by the Board, but will not increase the par value of the common stock and will not change the number of authorized shares of the common stock. If the Board does not implement an approved Reverse Stock Split prior to the one-year anniversary of this meeting, the Board will seek stockholder approval before implementing any Reverse Stock Split after that time.

By approving proposal 4 and the Reverse Stock Split, stockholders will approve the amendment to our certificate of incorporation pursuant to which any whole number of outstanding shares, between and including ten and twenty, would be combined into one share of common stock and authorize our Board to file one certificate of amendment, as determined by our Board in the manner described herein. If approved, our Board may also elect not to effect any Reverse Stock Split and consequently not file any certificate of amendment to the certificate of incorporation.

Nasdaq Listing Compliance

Our common stock is listed on the Nasdaq Global Select Market under the symbol “CALA.” To maintain a listing on the Nasdaq Global Select Market, we must satisfy various listing maintenance standards established by the Nasdaq. If we are unable to meet the Nasdaq Global Select Market requirements, our common stock will be subject to delisting.

Among other things, we are required to comply with the continued listing requirements of the Nasdaq Global Select Market, including that the common stock maintain a minimum bid price of $1.00 on the Nasdaq Global Select Market, or the Nasdaq Capital Requirement. We do not currently satisfy this Nasdaq Capital Requirement. Assuming our stockholders approve this proposal, our Board will determine whether to effect a Reverse Stock Split in the range of between one-for-ten and one-for-twenty, inclusive, at the ratio determined by our Board to be most likely sufficient to allow us to meet and maintain the $1.00 minimum bid price requirement.

Reasons for the Reverse Stock Split

On December 30, 2021, Nasdaq notified us that the bid price of our common stock had closed below the required $1.00 per share for 30 consecutive trading days, and, accordingly, that we did not comply with the applicable Nasdaq Capital Requirement. We have been provided 180 calendar days by Nasdaq to regain compliance with this requirement, or the Grace Period, subject to a potential 180 calendar day extension, as described below. To regain compliance, the closing bid price of the common stock must be at least $1.00 per share for a minimum of ten consecutive business days within the Grace Period.

If we do not achieve compliance with the Nasdaq Capital Requirement by June 28, 2022, the end of the Grace Period, we may be eligible for an additional 180 calendar day period to regain compliance. To qualify, we would be required to meet the continued listing requirement for the market value of its publicly held shares and all other

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Nasdaq initial listing standards, with the exception of the Nasdaq Capital Requirement, and would need to provide written notice of its intention to cure the deficiency during the second compliance period. However, if it appears to Nasdaq staff that we will not be able to cure the deficiency, or if we do not meet the other listing standards, Nasdaq could provide notice that the common stock will be subject to delisting. In the event we receive notice that the common stock is being delisted, we would be entitled to appeal the determination to a Nasdaq Listing Qualifications Panel and request a hearing.

Our Board has considered the potential harm to us of a delisting of the common stock and has determined that, if the common stock continues to trade below $1.00 per share, the consummation of the Reverse Stock Split is the best way to maintain liquidity by achieving compliance with the Nasdaq Capital Requirement. Our Board also believes that the current low per share market price of the common stock has a negative effect on the marketability of our existing shares. Our Board believes there are several reasons for this effect. First, certain institutional investors have internal policies preventing the purchase of low-priced stocks. Second, a variety of policies and practices of broker-dealers discourage individual brokers within those firms from dealing in low-priced stocks. Third, because the brokers’ commissions on low-priced stocks generally represent a higher percentage of the stock price than commissions on higher priced stocks, the current share price of the common stock can result in individual stockholders paying transaction costs (commissions, markups or markdowns) that are a higher percentage of their total share value than would be the case if the share price of the common stock were substantially higher. This factor is also believed to limit the willingness of some institutions to purchase the common stock. Our Board anticipates that a Reverse Stock Split will result in a higher bid price for our common stock, which may help to alleviate some of these problems.

If this proposal 4 is approved by the holders of the common stock and Series A preferred stock voting together as a single class and our Board decides to implement the Reverse Stock Split, our Board will determine the ratio of the Reverse Stock Split, in the range of between one-for-ten and one-for-twenty, inclusive, as determined in the judgment of our Board to be most likely sufficient to allow us to achieve and maintain compliance with the minimum $1.00 per share requirement for listing on the Nasdaq Global Select Market for the longest period of time while retaining a sufficient number of outstanding, tradeable shares to facilitate an adequate market.

We believe that maintaining listing on the Nasdaq Global Select Market will provide us with a market for the common stock that is more accessible than if the common stock were traded on the OTC Bulletin Board or in the “pink sheets” maintained by the OTC Markets Group, Inc. Such alternative markets are generally considered to be less efficient than, and not as broad as, the Nasdaq Global Select Market. Among other factors, trading on the Nasdaq Global Select Market increases liquidity and may potentially minimize the spread between the “bid” and “asked” prices quoted by Market Makers (as defined in Nasdaq Rule 5005). Further, a Nasdaq Global Select Market listing may enhance our access to capital, increase our flexibility in responding to anticipated capital requirements and facilitate the use of our common stock in any strategic or financing transactions that we may undertake. We believe that prospective investors will view an investment in us more favorably if our shares qualify for listing on the Nasdaq Global Select Market as compared with the OTC markets.

Effects of the Reverse Stock Split

The Reverse Stock Split will be effected simultaneously for all issued and outstanding shares of common stock and the Reverse Stock Split ratio will be the same for all issued and outstanding shares of common stock. The Reverse Stock Split will affect all of our stockholders uniformly and will not affect any stockholder’s percentage ownership interests in Calithera, except that stockholders who would have otherwise received fractional shares will receive cash in lieu of such fractional shares. After the Reverse Stock Split, each share of the common stock will have the same voting rights and rights to dividends and distributions and will be identical in all other respects to the common stock now authorized and common stock issued pursuant to the Reverse Stock Split will remain fully paid and non-assessable. The Reverse Stock Split is not intended as, and will not have the effect of, a “going private transaction” covered by Rule 13e-3 under the Securities Exchange Act enableof 1934, as amended. We will continue to be subject to the Company’s stockholders,periodic reporting requirements of the Securities Exchange Act of 1934, as amended.

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The following table sets forth the number of shares of the common stock that would be outstanding immediately after the Reverse Stock Split at least once every six years, to indicate their preference regarding how frequently the Company should solicita non-binding advisory votevarious exchange ratios, based on the compensation97,236,174 shares of common stock outstanding as of April 4, 2022. The table does not account for fractional shares that will be paid in cash.

If a stockholder owns 10,000 shares of common stock prior to the Reverse Stock Split, after the Reverse Stock Split that same stockholder would own:

Accounting Matters

The Reverse Stock Split will not affect the par value of the Company’s named executive officerscommon stock. As a result, upon the effectiveness of the Reverse Stock Split, the stated capital on our balance sheet attributable to the common stock will be reduced proportionately based on the exchange ratio selected by our Board for the Reverse Stock Split, and the additional paid-in capital account will be credited with the amount by which the stated capital is reduced. The per share net income or loss and net book value of the common stock will be increased because there will be fewer shares of common stock outstanding. In addition, proportionate adjustments will be made to the per share exercise price and the number of shares issuable upon the exercise or settlement of all outstanding options, restricted stock units and warrants to purchase or acquire, as disclosedapplicable, shares of common stock, and the number of shares reserved for issuance pursuant to our existing equity incentive, stock option and employee stock purchase plans will be reduced proportionately based on the exchange ratio selected by the Board for the Reverse Stock Split.

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No Fractional Shares

No fractional shares of common stock will be issued as a result of the Reverse Stock Split. Instead, stockholders who otherwise would be entitled to receive fractional shares will be entitled to receive cash in an amount equal to the product obtained by multiplying (i) the closing sales price of the common stock as reported on the Nasdaq Global Select Market on the effective date of the certificate of amendment to the Certificate of Incorporation by (ii) the number of shares of common stock held by such stockholder before the Reverse Stock Split that would otherwise have been exchanged for such fractional share interest. Holders of as many as 19 shares (if we were to implement a 1-for-20 Reverse Stock Split) of common stock would be eliminated as a result of the cash payment in lieu of any issuance of fractional shares or interests in connection with the Reverse Stock Split. The exact number by which the number of holders of the common stock would be reduced will depend on the Reverse Stock Split ratio adopted and the number of stockholders that hold less than the Reverse Stock Split ratio as of the effective date of the Reverse Stock Split. As of the record date, there were approximately twenty holders of record of the common stock, of which one was a holder of fewer than 20 shares of common stock. As a result of the Reverse Stock Split, assuming the maximum Reverse Stock Split ratio of 1-for-20 were selected, we estimate that cashing out fractional stockholders would potentially reduce that number of stockholders of record to             .

Certain Risks Associated with the Reverse Stock Split

Before voting on this proposal 4, stockholders should consider the following risks associated with effecting a Reverse Stock Split:

The

Potential Anti-Takeover Effect of the Reverse Stock Split

Upon effectiveness of the Reverse Stock Split, the number of authorized shares of common stock that are not issued or outstanding will increase relative to the number of shares of common stock that are issued and

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outstanding prior to the Reverse Stock Split. While this increase could, under certain circumstances, have an annual advisory voteanti-takeover effect (for example, by permitting issuances that would dilute the stock ownership of a person seeking to effect a change in the composition of the Board or contemplating a tender offer or other transaction for the combination of Calithera with another company), proposal 4 is not being proposed in response to any effort of which we are aware to accumulate shares of the common stock or to obtain control of Calithera.

Effective Date

If our stockholders approve the Reverse Stock Split, the Reverse Stock Split would become effective at such time as it is deemed by our Board to be in the best interests of Calithera and our stockholders and we file the amendment to our certificate of incorporation. Even if the Reverse Stock Split is approved by our stockholders, our Board has discretion not to carry out or to delay in carrying out the Reverse Stock Split. Upon the filing of the amendment, all of the pre-Reverse Stock Split shares will be converted into new common stock as set forth in the amendment.

Exchange of Stock Certificates

Some stockholders hold their shares of common stock in certificate form or a combination of certificate and book-entry form. Our transfer agent will act as the “exchange agent” for purposes of implementing the exchange of stock certificates. Stockholders holding pre-split shares that are certificated will be asked to surrender to the exchange agent certificates representing pre-split shares in exchange for certificates representing post-split shares in accordance with the procedures to be set forth in a letter of transmittal to be sent by the exchange agent. No new certificates will be issued to a stockholder until such stockholder has surrendered the stockholder’s outstanding certificate(s) together with the properly completed and executed letter of transmittal to the exchange agent.

STOCKHOLDERS SHOULD NOT DESTROY ANY STOCK CERTIFICATE(S) AND SHOULD NOT SUBMIT ANY CERTIFICATE(S) UNTIL REQUESTED TO DO SO.

Certain Material U.S. Federal Income Tax Consequences of the Reverse Stock Split

The following is a summary of certain material federal income tax consequences of the Reverse Stock Split that generally are expected to be applicable to U.S. Holders (as defined below) of the common stock, but does not purport to be a complete discussion of all of the potential tax considerations relating thereto. This summary is based on the compensationprovisions of the Company’s named executive officersUnited States federal income tax law (including the Internal Revenue Code of 1986, as amended, or the Code, applicable Treasury Regulations promulgated thereunder, and judicial authorities and current administrative rulings and practices as in effect on the date of this proxy statement). Changes to these laws could alter the tax consequences described below, possibly with retroactive effect, which may result in the U.S. federal income tax consequences of the Reverse Stock Split differing substantially from the consequences summarized below. We have not sought and will not seek an opinion of counsel or a ruling from the Internal Revenue Service regarding the U.S. federal income tax consequences of the Reverse Stock Split, and there can be no assurance that the Internal Revenue Service or the courts will accept the positions expressed below. This summary assumes that the common stock will be, both before and after the Reverse Stock Split, held as a “capital asset,” as defined in the Code (i.e., generally, property held for investment). Further, it does not discuss the tax consequences of the Reverse Stock Split under state, local, foreign laws or under gift, excise or other non-income tax laws, or the application of the alternative minimum tax rules, the Medicare contribution tax on net investment income or the special tax accounting rules under Section 451(b) of the Code. This summary does not address the tax consequences of transactions effectuated prior or subsequent to, or concurrently with, the Reverse Stock Split (whether or not any such transactions are consummated in connection with the Reverse Stock Split), or the tax consequences to holders of options, warrants or similar rights to acquire common stock. In addition, this summary does not address the tax consequences applicable to a holder’s particular circumstances or to holders that are subject to special tax rules, including without limitation banks, financial institutions, insurance

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companies, regulated investment companies, mutual funds, real estate investment trusts, personal holding companies, foreign entities, nonresident alien individuals, broker-dealers, traders, tax-exempt entities, persons who hold common stock as a position in a hedging transaction, “straddle,” “conversion transaction” or other integrated or risk reduction transaction, persons whose common stock constitute qualified small business stock within the meaning of Section 1202 of the Code, holders who hold their common stock through individual retirement or other tax-deferred accounts, holders of common stock who are not U.S. Holders (as defined below), holders of common stock who have a functional currency for U.S. federal income tax purposes other than the U.S. dollar, holders who acquired their common stock in a transaction subject to the gain rollover provisions of Section 1045 of the Code, holders who acquired their common stock pursuant to the exercise of employee stock options or otherwise as compensation, or holders of common stock who are partnerships, limited liability companies that are not treated as corporations for U.S. federal income tax purposes, S corporations, or other pass-through entities or investors in such pass-through entities.

For purposes of this discussion, a U.S. Holder means a beneficial owner of common stock that is: (i) an individual who is a citizen or resident of the most appropriate frequencyUnited States; (ii) a corporation (or other entity taxable as a corporation for us at this time. Accordingly,U.S. federal income tax purposes) created or organized in the BoardUnited States or under the laws of the United States or any subdivision thereof, or the District of Columbia; (iii) an estate the income of which is asking shareholdersincludible in gross income for U.S. federal income tax purposes regardless of its source; or (iv) a trust (other than a grantor trust) if (A) a court within the United States is able to indicate their preferred voting frequency by votingexercise primary supervision over the administration of the trust and one or more U.S. persons have the authority to control all substantial decisions of the trust or (B) it has a valid election in effect under applicable U.S. Treasury regulations to be treated as a U.S. person.

THIS SUMMARY OF CERTAIN MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE REVERSE STOCK SPLIT IS FOR GENERAL INFORMATION ONLY AND IS NOT TAX ADVICE. EACH STOCKHOLDER IS URGED TO CONSULT WITH SUCH STOCKHOLDER’S OWN TAX ADVISOR WITH RESPECT TO THE TAX CONSEQUENCES OF THE REVERSE STOCK SPLIT.

Tax Consequences of the Reverse Stock Split

The Reverse Stock Split should constitute a “recapitalization” for one, two or three years or abstaining from voting on this proposal. The alternative among one year, two years or three yearsU.S. federal income tax purposes. A U.S. Holder that receives solely a reduced number of shares of common stock generally will not recognize gain or loss in the votesReverse Stock Split. A U.S. Holder’s aggregate tax basis in the reduced number of shares of common stock should equal the U.S. Holder’s aggregate tax basis in its pre-Reverse Stock Split shares of common stock, and such U.S. Holder’s holding period in the reduced number of shares of common stock should include the holding period in its pre-Reverse Stock Split shares of common stock exchanged. Treasury Regulations provide detailed rules for allocating the tax basis and holding period of the shares of common stock surrendered to the shares of common stock received in a recapitalization pursuant to the Reverse Stock Split. U.S. Holders should consult their tax advisors as to application of the foregoing rules where shares of common stock were acquired at different times or at different prices.

No gain or loss will be recognized by Calithera as a result of the proposed Reverse Stock Split.

Cash in Lieu of Fractional Shares

A U.S. Holder that receives cash in lieu of fractional share interests as a result of the Reverse Stock Split will be treated as having received the fractional shares pursuant to the Reverse Stock Split and then as having exchanged the fractional shares for cash in a redemption by Calithera, and generally should recognize gain or loss equal to the difference, if any, between the amount of cash received in lieu of a fractional share and its adjusted basis allocable to the fractional share interests. Such gain or loss will be long-term capital gain or loss if the pre-Reverse Stock Split shares were held for more than one year. Long-term capital gains of individuals are generally subject to tax at reduced rates. There are limitations on the deductibility of capital losses under the

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Code. A U.S. Holder’s aggregate tax basis in the reduced number of shares of common stock, if any, should equal the U.S. Holder’s aggregate tax basis in its pre-Reverse Stock Split shares of common stock decreased by the basis allocated to the fractional share for which such U.S. Holder is entitled to receive cash, and the holding period of the reduced number of shares of common stock received, if any, should include the holding period of the pre-Reverse Stock Split shares of common stock exchanged.

Information Reporting and Backup Withholding

A holder of common stock may be subject to information reporting and backup withholding on cash paid in lieu of fractional shares in connection with the Reverse Stock Split. To avoid backup withholding, each holder of common stock that does not otherwise establish an exemption should provide its taxpayer identification number and comply with the applicable certification procedures. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules generally will be allowed as a refund or credit against a U.S. Holder’s U.S. federal income tax liability, provided the required information is timely and properly furnished to the Internal Revenue Service. Holders of common stock should consult their tax advisors regarding their qualification for an exemption from backup withholding and the procedures for obtaining such an exemption, as well as the procedures for obtaining a credit or refund if backup withholding is imposed.

THE PRECEDING DISCUSSION IS INTENDED ONLY AS A SUMMARY OF CERTAIN MATERIAL U.S. FEDERAL INCOME TAX CONSEQUENCES OF THE REVERSE STOCK SPLIT TO U.S. HOLDERS. IT IS NOT A COMPLETE ANALYSIS OR DISCUSSION OF ALL POTENTIAL TAX EFFECTS THAT MAY BE IMPORTANT TO A PARTICULAR HOLDER. ALL HOLDERS OF OUR COMMON STOCK SHOULD CONSULT THEIR OWN TAX ADVISORS AS TO THE SPECIFIC TAX CONSEQUENCES OF THE REVERSE STOCK SPLIT TO THEM, INCLUDING RECORD RETENTION AND TAX-REPORTING REQUIREMENTS, AND THE APPLICABILITY AND EFFECT OF ANY U.S. FEDERAL, STATE, LOCAL AND NON-U.S. TAX LAWS.

No Dissenters’ Rights

Under applicable Delaware law, our stockholders are not entitled to dissenters’ or appraisal rights with respect to our proposed amendment to the certificate of incorporation to effect the Reverse Stock Split. We will not independently provide our stockholders with any such right.

Vote Required

The affirmative vote of the holders of a majority of all outstanding shares present online duringof the virtual meeting or represented by proxycommon stock and entitled to voteSeries A preferred stock (on an as-converted basis) voting together as a single class on the matter at the 2020 Annual Meeting will be deemed to be the frequency preferred by the shareholders.

While the Board believes that its recommendationrecord date is appropriate at this time, the stockholders are not voting to approve or disapprove that recommendation, but are instead asked to indicate their preferences, on an advisory basis, as to whetherthe non-binding advisory vote on therequired for approval of the Company’s executive officer compensation practices should be held every year, every other year, or every three years. The option among those choicesproposed amendment to our certificate of incorporation to effect a Reverse Stock Split set forth in this proposal 4. Our existing certificate of designations provides that receives the votesholder of our Series A preferred stock shall vote together with the holders of the common stock as a majoritysingle class. The number of votes that the holder of the voting powerSeries A preferred stock is entitled to cast is based on the number of shares of common stock that the shares present in person or represented by proxy and entitled to vote at the 2020 Annual Meeting will be deemed to be the frequencyof Series A preferred by the stockholders. In the event that no option receives a majority of the votes, the Company will consider the option that receives the most votes cast to be the frequency preferred by our stockholders.

The Board and the Compensation Committee value the opinions of the stockholders in this matter and,stock are convertible into, subject to the extent“Share Cap” described in our certificate of designations. The Share Cap is defined to mean shares of common stock equal to 14,817,484 (or (i) 0.1999 multiplied by (ii) 74,124,484). Because proposal 4 is considered “routine” for these purposes, there is any significant vote in favor of one frequency over the other options, even if less than a majority, the Board will consider the stockholders’ concerns and evaluate any appropriate next steps. However, because this vote is advisory and, therefore, not binding on the Board or the Company, the Board may decide that it is in the best interests of the stockholders that the Company hold an advisory vote on executive compensation more or less frequently than the option preferred by the stockholders. The vote will not be construed to create or imply any change or addition to the fiduciary duties of the Company or the Board.broker non-votes for this proposal.

THE BOARD RECOMMENDS

A VOTEIN FAVOROF “OPNEROPOSAL YNEARO”. 4.

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PROPOSAL NO. 5

APPROVALOFTHE ISSUANCEOF MORE THAN 20%OFOUR ISSUEDAND ONUTSTANDING COMMON STOCK

Background and Description of Transaction

On October 18, 2021, we entered into a Preferred Stock Purchase Agreement with Millennium Pharmaceuticals, Inc., or Millennium, a wholly-owned subsidiary of Takeda Pharmaceutical Company Limited, or Takeda, as part of an agreement to acquire from Millennium two clinical-stage compounds as well as other technology, intellectual property and assets related to Takeda’s small molecule programs, TAK-228 and TAK-659 (now CB-228 and CB-659), or the Transaction. Pursuant to the Preferred Stock Purchase Agreement, we issued to Millennium 1,000,000 shares of Series A preferred stock initially convertible into an aggregate of 17,156,863 shares of common stock, subject to price-based anti-dilution adjustments that if triggered would result in the issuance of additional shares of common stock, at a valuation of $2.04 per equivalent one share of common stock for an aggregate deemed issue price of $35 million. We closed the Transaction on October 18, 2021, or the Closing Date.

In connection with the Transaction, we agreed to seek approval of our stockholders for the issuance of shares of common stock in excess of the “Share Cap” (as defined in the Certificate of Designations of Preferences, Rights and Limitations of the Series A Convertible Preferred Stock filed with the Secretary of State of the State of Delaware on the Closing Date, or the Certificate of Designations), with the recommendation of our Board that such proposal be approved. We are not seeking stockholder approval of, and you are not being asked to vote on, the transaction, but rather the conversion of the Series A preferred stock into common stock with such “full-ratchet”, anti-dilution price protections as in effect pursuant to the Certificate of Designations.

Pursuant to the Certificate of Designations, the Series A preferred stock has an original issue price of $35.00 per share and is initially convertible into 17,156,863 shares of common stock, representing 23.8% of our outstanding common stock immediately prior to the Closing Date. The Series A preferred stock will automatically convert, subject to certain beneficial ownership limitations, on the earlier of (i) the 18-month anniversary of the date of issuance and (ii) a “Qualified Financing” (as defined in the Certificate of Designations), in each case, into 17,156,863 shares of common stock, subject to certain price-based anti-dilution adjustments. The Series A preferred stock is also convertible, subject to certain beneficial ownership limitations, at the option of the holder thereof, at any time prior to automatic conversion into 17,156,863 shares of common stock. However, until this proposal 5 is approved by stockholders, Millennium may only convert its shares of Series A preferred stock into an aggregate of 14,817,484 shares of common stock, representing 19.99% of the outstanding shares of common stock immediately prior to the Closing Date.

The conversion price of the Series A preferred stock is subject to certain anti-dilution protections that if triggered will result in additional shares of common stock being issued upon conversion of the Series A preferred stock. If the volume weighted percentage price of our common stock for the 30 trading days prior to the 18-month anniversary of the date of issuance is lower than $2.04 per share, then the conversion price of the Series A preferred stock will be reduced to such lower price. In addition, if we sell or grant any common stock or any of our securities following the Closing Date that would entitle the holder thereof to acquire common stock at an effective price per share that is lower than the applicable conversion price of the Series A preferred stock, then the conversion price of the Series A preferred stock will be reduced to such lower price. This is commonly referred to as “full-ratchet” anti-dilution protection. The effect of such reduction is that, upon the issuance of shares of common stock at such lower price, the Series A preferred stock would become convertible into a greater number of shares of our common stock. In addition, if in connection with a Qualified Financing, we issue warrants or other derivative securities to purchase our capital stock, then we will offer to issue to Millennium, upon payment of the same consideration as received by us from such investors for such warrants or other derivative securities, such number of warrants or other derivative securities in the same form and in the same percentage as issued in the Qualified Financing.

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If our stockholders do not approve this proposal 5 to allow for the conversion of all of the shares of Series A preferred stock to common stock, and as a result Millennium is unable to convert any portion of the Series A preferred stock to common stock, then we will negotiate with Millennium in good faith the timing and amount per share to be paid to compensate Millennium for such inability to convert; provided that we will not be required to pay Millennium any cash for three years after the date of issuance unless we have closed an equity financing of at least $80.0 million with a volume weighted average price of at least $2.04 per share then we shall instead pay Millennium $2.04 per share of Series A preferred stock that Millennium is unable to convert.

If our stockholders approve this proposal 5 to allow for the conversion of all of the shares of Series A preferred stock to common stock, but Millennium is unable to convert as a result of the “Accounting Cap” (as defined in the Certificate of Designations) any portion of the Series A preferred stock to common stock by October 18, 2026, then on each yearly anniversary thereafter, any shares of Series A preferred stock that remain outstanding shall automatically be converted into common stock at the applicable conversion ratio, in each case subject to the Accounting Cap, until such point in time as all shares of Series A preferred stock have been converted.

Why We Are Seeking Stockholder Approval

Our common stock is currently listed on the Nasdaq Global Select Market and as a result, issuances of our common stock are subject to the Nasdaq Listing Rules. In particular, the issuance of the Series A preferred stock to Millennium requires stockholder approval pursuant to Nasdaq Listing Rule 5635(d) and 5635(b).

Under Nasdaq Listing Rule 5635(d), stockholder approval is required for a transaction other than a public offering involving the sale, issuance or potential issuance by an issuer of common stock (or securities convertible into or exercisable for common stock) if the number of shares of common stock to be issued is or may be equal to 20% or more of the common stock, or 20% or more of the voting power, outstanding before the issuance, at a price that is less than the “minimum price”, defined as the lower of the closing price immediately preceding the signing of the binding agreement or the average closing price of the common stock for the five trading days immediately preceding the signing of the binding agreement. The Series A preferred stock was issued to Millennium in a private placement and although such shares were issued at an effective “minimum price” of $2.04 per share of common stock, the conversion price of the Series A preferred stock is subject to certain anti-dilution protections that if triggered will result in an effective conversion price that is less than the “minimum price.”

Under Nasdaq Listing Rule 5635(b), stockholder approval is required prior to the issuance of securities when the issuance or potential issuance will result in a change of control of a company. This rule does not specifically define when a change in control of a company may be deemed to occur for this purpose; however, Nasdaq suggests in its guidance that a change of control would occur, subject to certain limited exceptions, if after a transaction an investor (or a group of investors) would hold 20% or more of a company’s then-outstanding capital stock. Until this proposal 5 is approved by stockholders, Millennium may only convert its shares of Series A preferred stock into an aggregate of 14,817,864 shares of common stock, representing 19.99% of the outstanding shares of common stock immediately prior to the Closing Date. If this proposal 5 is approved, the Series A preferred stock will be convertible (prior to the application of any anti-dilution protections) into a minimum of 17,156,863 shares of common stock assuming an effective conversion price of $2.04 per share. As discussed below, the conversion price of the Series A preferred stock is subject to certain anti-dilution protections that if triggered will result in additional shares of common stock being issued upon conversion of the Series A preferred stock.

If our stockholders do not approve this proposal 5, then we will only be able to issue Millennium a maximum of 14,817,864 shares of common stock.

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Effect on the Rights of Existing Common Stockholders

Dilutive Effect of Issuances of Common Stock

Upon stockholder approval of proposal 5, the Series A preferred stock will not be subject to the “Share Cap” and may be converted into common stock at the election of Millennium, resulting in a potential issuance of at least 17,156,863 shares of common stock. If the price-based anti-dilution adjustments are triggered the conversion of the Series A preferred stock would result in the issuance of additional shares of common stock at the time of conversion. If the price-based “full ratchet” anti-dilution occurs, it would result in significant dilution in ownership interests and voting rights to our stockholders.

For illustrative purposes only, the table below shows the number of shares of common stock that would be issuable upon conversion of the Series A preferred stock if (i) the volume weighted-average price of our common stock for the 30 trading days prior to the 18-month anniversary of the date of issuance is lower than $2.04 per share, or (ii) we issue securities at an effective price per share that is lower than $2.04 per share, thereby resulting in the issuance of more than 17,156,863 shares of common stock:

OFFICERS

The following table sets forth certain information with respect to our executive officers and directors as of March 31, 2020.2022.

Dr. Susan M. Molineaux’s biography is included above under the section titled “Proposal No. 1 – Election of Directors.”

Curtis C. Hecht.Emil T. Kuriakose, M.D.Mr. Hecht joined Calithera in April 2014 and currently serves Dr. Kuriakose has served as our Chief Business Officer. He has over 20 years of pharmaceutical research and development, commercialization, corporate strategy and business development experience, and has led or supported over $50 billion in strategic transactions.Medical Officer since November 2021. From September 2013October 2017 to April 2014, Mr. Hecht served as Vice President of Business Development at inVentiv Health, a global healthcare commercialization and consulting services company. Since 2011, Mr. Hecht has alsoFebruary 2020, he served as a PartnerSenior Medical Director and then as our Vice President, Clinical Development since February 2020 and Head of Clinical Development since January 2021. Dr. Kuriakose previously served at DNA Ink, a life sciences business developmentNovartis AG as Global Clinical Program Lead at the Novartis Institute for Biomedical Research from January 2016 to September 2017 and strategy consulting firm. Prioras Medical Director at Novartis Oncology from July 2013 to that, Mr. Hecht served in a number of roles at Genentech and HoffmannLa-Roche Inc., including Global Alliance Director, where he managed aspects ofJanuary 2016. At Novartis, Dr. Kuriakose led the Roche-Genentech collaboration, was a member of the JointU.S. Clinical Development and Operations Committee with oversite ofMedical Affairs Group for Farydak (panobinostat), supporting the jointnew drug application filing and launch in multiple myeloma. He subsequently led early phase development of Herceptin^®, Avastin^®, Rituxan^®, Erivedge^®, Kadcyla^®,several drugs in solid and Tarceva^®,hematologic malignancies as Global Clinical Program Lead at the Novartis Institute for Biomedical Research (NIBR). Dr. Kuriakose completed his clinical training in hematology/oncology at Weill Cornell Medical College, including a research fellowship in myeloproliferative neoplasms at Memorial Sloan Kettering Cancer Center. He completed his residency training in internal medicine at UT Southwestern Medical Center in Dallas, Texas. Dr. Kuriakose received his M.D. from Stony Brook University School of Medicine and was core team member in Roche’s $46.8 billion acquisition of Genentech in March 2009. As Director of Global Business Development, he evaluated and negotiated oncology licensing and M&A transactions. As Director of Marketing, he planned and executed the commercial launch of Xeloda^® in adjuvant colorectal cancer and broadly managed brand promotions. Mr. Hecht received ahis B.S. in Chemistry with a concentration in Physicsneuroscience from California State University, Sacramento, and an MBA with concentrations in Marketing, Strategy, and Finance from Carnegie Mellon University, Tepper School of Business.New York University.

Christopher J. Molineaux, Ph.D. Dr. Molineaux joined Calithera in April 2013 and currently serves as our Senior Vice President of Development. From March 2010 to March 2013, Dr. Molineaux served as the President of INDStrat LLC, a consulting firm. From July 2004 to November 2009, Dr. Molineaux served as Vice President of Development at Proteolix, Inc. From 2000 to 2004, Dr. Molineaux served as Senior Director of Drug Development at FibroGen, Inc., a biotechnology company. From 1999 to 2000, he served as Research Manager of Toxicology at Johnson & Johnson Pharmaceutical Research and Development. From 1994 to 1999, Dr. Molineaux served as Senior Director of Pharmacology at Praecis. From 1991 to 1994, he served in staff scientist positions at Enzon Pharmaceuticals, Inc. and Merck & Co. From 1985 to 1991, Dr. Molineaux served as an Assistant Professor of Pharmacology of Mount Sinai School of Medicine in New York City. He received a B.S. in Zoology from University of Maryland, College Park, a Ph.D. in Immunology and Infectious Diseases from Johns Hopkins University and completed his postdoctoral fellowship at the Uniformed Services University of the Health Sciences.

Keith Orford, M.D, Ph.D. Dr. Orford joined Calithera in January 2015 and currently serves as our Chief Medical Officer. Prior to joining Calithera in January 2015, Dr. Orford was the Clinical Development Lead in the

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Chemistry at Roche Palo Alto, LLC, where he directed a small molecule drug discovery team in the areas of inflammation, virology and central nervous system disorders. Dr. Sjogren received a B.A. in Chemistry from the University of California, San Diego and a Ph.D. in Chemistry from Harvard University.

Stephanie Wong.Ms. Wong joined Calithera in April 2014 and currently serveshas served as our Chief Financial Officer since January 2021, and as Secretary since January 2017. From 2018 to 2020, Ms. Wong served as our Senior Vice President of Finance and Secretary.from 2014 to 2017 as Vice President of Finance. From 2009 to 2013, Ms. Wong was at SciClone Pharmaceuticals, Inc., a publicly traded, commercial-stage pharmaceutical company, most recently as Vice President, Finance and Controller. From 2008 to 2009, Ms. Wong was Senior Director, Finance at AcelRx Pharmaceuticals Inc. From 2001 to 2008, Ms. Wong held various positions at Kosan Biosciences Inc., a publicly traded biotechnology company until its acquisition by Bristol-Myers Squibb Co., most recently as Senior Director and Controller. Prior to that, Ms. Wong workedserved in senior finance roles at AcelRx Pharmaceuticals, Inc. and Kosan Biosciences, Inc., both biopharmaceutical companies, and as an audit manager at PricewaterhouseCoopers LLP.LLP, an independent registered public accounting firm. Ms. Wong currently serves on the board of directors of AN2 Therapeutics, Inc. Ms. Wong received a B.S. in Business Administration from the University of California, Berkeley and is a Certified Public Accountant (inactive) in the State of California.

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SECURITY OWNERSHIPOF

CERTAIN BENEFICIAL OWNERSAND MANAGEMENT

The following table sets forth certain information regarding the ownership of our common stock as of March 31, 2020April 4, 2022 by:

This table is based upon information supplied by officers, directors and principal stockholders and Schedules 13D and 13G filed with the SEC. Unless otherwise indicated in the footnotes to this table and subject to community property laws where applicable, the Company we believe that each of the stockholders named in this table has sole voting and investment power with respect to the shares indicated as beneficially owned. Applicable percentages are based on 64,692,683112,053,658 shares outstanding on April 13, 2020,4, 2022, assuming the conversion of 14,817,484 shares of common stock upon conversion of the Series A preferred stock, adjusted as required by rules promulgated by the SEC.

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EXECUTIVE COMPENSATION

Our named executive officers for the year ended December 31, 2021, consisting of our principal executive officer, the two other most highly compensated executive officers serving at the end of such year, and one former executive officer, were:

SUMMARY COMPENSATION TABLE

The following table shows forpresents all of the compensation awarded to, earned by or paid to our named executive officers during the years ended December 31, 20192021 and 2018, compensation awarded to or paid to, or earned by, our Chief Executive Officer and two other most highly compensated executive officers at December 31, 2019 (the “Named Executive Officers”).

SUMMARY COMPENSATION TABLE FOR FISCAL 20192020.

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OUTSTANDING EQUITY AWARDSAT DECEMBER 31, 20192021

The following table shows, certain information regarding outstanding equity awards at December 31, 2019,2021, for the Named Executive Officers.

OUTSTANDING EQUITY AWARDS AT DECEMBER 31, 2019named executive officers.