UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

PROXY STATEMENT PURSUANT TO SECTION 14(a) OF THE

SECURITIES EXCHANGE ACT OF 1934

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

Check the appropriate box:

ALX Oncology Holdings Inc.

(Name of Registrant as Specified In Its Charter)

Payment of Filing Fee (Check all boxes that apply):

April 20, 2026

Dear Stockholder:

We are pleased to invite you to attend the 2026 Annual Meeting of Stockholders (the Annual Meeting) of ALX Oncology Holdings Inc. (ALX or the Company), which will be conducted via a live webcast on Wednesday, June 10, 2026 at 1:00 p.m. Pacific Time. The Annual Meeting will be held in a virtual format only. You will be able to attend the Annual Meeting by visiting www.virtualshareholdermeeting.com/ALXO2026, where you will be able to listen to the meeting live, submit questions and vote online by entering the control number located on your proxy card.

The attached Notice of Annual Meeting of Stockholders and Proxy Statement contain details of the business to be conducted at the Annual Meeting.

Whether or not you attend the virtual Annual Meeting, it is important that your shares be represented and voted at the meeting. Therefore, we urge you to promptly vote and submit your proxy via the Internet, by phone, or by signing, dating and returning the enclosed proxy card in the enclosed envelope. If you decide to attend the Annual Meeting, you will be able to change your vote or revoke your proxy, even if you have previously submitted your proxy.

On behalf of the Company’s Board of Directors, we would like to thank you for your continued support of and interest in ALX.

Sincerely,

ALX ONCOLOGY HOLDINGS INC.

323 Allerton Avenue

South San Francisco, California 94080

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

YOUR VOTE IS IMPORTANT. Whether or not you plan to attend the Annual Meeting virtually, we urge you to submit your vote via the Internet, telephone or mail as soon as possible to ensure your shares are represented. For additional instructions for each of these voting options, please refer to the proxy card. Returning the proxy does not deprive you of your right to attend the Annual Meeting and to vote your shares at the Annual Meeting. The proxy statement explains proxy voting and the matters to be voted on in more detail.

Important Notice Regarding the Availability of Proxy Materials for the Annual Meeting to Be Held on June 10, 2026. Our proxy statement and Annual Report to Stockholders are being made available on or about April 20, 2026 on our investor relations website at https://ir.alxoncology.com/ under “Financials & Filings.” We are providing access to our proxy materials over the Internet under the rules adopted by the Securities and Exchange Commission.

By order of the Board of Directors,

Jason Lettmann

Chief Executive Officer and Director

South San Francisco, California

April 20, 2026

This proxy statement is being mailed to stockholders on or about April 20, 2026.

TABLE OF CONTENTS

ALX ONCOLOGY HOLDINGS INC.

PROXY STATEMENT

FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS

To Be Held at 1:00 p.m. Pacific Time on Wednesday, June 10, 2026

This proxy statement and the enclosed form of proxy are furnished in connection with the solicitation of proxies by our board of directors for use at the 2026 annual meeting of stockholders of ALX Oncology Holdings Inc. (the Annual Meeting), and any postponements, adjournments or continuations thereof. The Annual Meeting will be held on Wednesday, June 10, 2026 at 1:00 p.m. Pacific Time virtually via a live webcast. You will be able to attend the Annual Meeting virtually by visiting www.virtualshareholdermeeting.com/ALXO2026, where you will be able to listen to the meeting live, submit questions and vote online by entering the control number on your proxy card.

QUESTIONS AND ANSWERS ABOUT THE ANNUAL MEETING

The information provided in the “question and answer” format below addresses certain frequently asked questions but is not intended to be a summary of all matters contained in this proxy statement. Please read the entire proxy statement carefully before voting your shares. Information contained on, or that can be accessed through, our website is not intended to be incorporated by reference into this proxy statement and references to our website address in this proxy statement are inactive textual references only.

Why am I receiving these materials?

Our board of directors is providing these proxy materials to you in connection with its solicitation of proxies for use at the Annual Meeting, which will take place on June 10, 2026. Stockholders are invited to attend the virtual Annual Meeting and are requested to vote on the proposals described in this proxy statement. This proxy statement and the accompanying proxy card are being mailed on or about April 20, 2026. The proxy materials and our Annual Report on Form 10-K as filed with the Securities and Exchange Commission (the SEC) on March 9, 2026 (the Annual Report) will also be accessible on the SEC’s website at www.sec.gov, and our investor relations website at https://ir.alxoncology.com.

What proposals will be voted on at the Annual Meeting?

There are three proposals scheduled to be voted on at the Annual Meeting:

At the time this proxy statement was mailed, our management and board of directors were not aware of any other matters to be presented at the Annual Meeting other than those set forth in this proxy statement and in the notice accompanying this proxy statement.

How does our board of directors recommend that I vote?

Our board of directors recommends that you vote:

Who is entitled to vote at the Annual Meeting?

Holders of our common stock at the close of business on April 15, 2026, the record date for the Annual Meeting (the Record Date), are entitled to notice of and to vote at the Annual Meeting. Each stockholder is entitled to one vote for each share of our common stock held as of the Record Date. As of the Record Date, there were 134,559,917 shares of common stock outstanding and entitled to vote. Stockholders are not permitted to cumulate votes with respect to the election of directors.

Stockholders of Record – Shares Registered in Your Name. If, at the close of business on the Record Date, your shares were registered directly in your name with Computershare Trust Company, N.A., our transfer agent, then you are considered the stockholder of record with respect to those shares, and this proxy statement was provided to you directly by us. As the stockholder of record, you have the right to grant your voting proxy directly to the individuals listed on the proxy card or to vote in person (including virtually) at the Annual Meeting. Throughout this proxy statement, we refer to these registered stockholders as “stockholders of record.”

Street Name Stockholders – Shares Registered in the Name of a Broker, Bank or Other Nominee. If, at the close of business on the Record Date, your shares were held, not in your name, but rather in a stock brokerage account or by a bank or other nominee on your behalf, then you are considered the beneficial owner of shares held in “street name,” and this proxy statement was forwarded to you by your broker or nominee, who is considered the stockholder of record with respect to those shares. As the beneficial owner, you have the right to direct your broker, bank or other nominee how to vote your shares by following the voting instructions your broker, bank or other nominee provides. If you do not provide your broker, bank or other nominee with instructions on how to vote your shares, your broker, bank or other nominee may, in its discretion, vote your shares with respect to routine matters but may not vote your shares with respect to any non-routine matters. Throughout this proxy statement, we refer to stockholders who hold their shares through a broker, bank or other nominee as “street name stockholders.”

How many votes are needed for approval of each proposal?

What is a quorum?

A quorum is the minimum number of shares required to be present at the Annual Meeting for the annual meeting of stockholders to be properly held under our amended and restated bylaws (Bylaws) and Delaware law. A majority of the shares of common stock outstanding and entitled to vote, in person (including virtually) or by proxy, constitutes a quorum for the transaction of business at the Annual Meeting. Abstentions, withhold votes, and broker non-votes are counted as shares present and entitled to vote for purposes of determining a quorum. If there is no quorum, a majority of the shares present at the Annual Meeting may adjourn the meeting to a later date.

What do I need to do to attend the Annual Meeting?

You will be able to attend the Annual Meeting virtually, submit your questions during the meeting and vote your shares electronically at the meeting by visiting www.virtualshareholdermeeting.com/ALXO2026. To participate in the Annual Meeting, you will need the control number from your proxy card. The Annual Meeting webcast will begin promptly at 1:00 p.m. Pacific Time. We encourage you to access the meeting prior to the start time. Online check-in will begin at 12:45 p.m. Pacific Time, and you should allow ample time for the check-in procedures.

Why is the Annual Meeting held virtually?

Our board of directors believes that a virtual Annual Meeting allows for participation by a broader group of stockholders, reduces the costs to stockholders associated with holding an in-person meeting, and is the best option for ensuring the health and safety of the participants. The virtual meeting format is intended to facilitate a level of transparency as close as possible to an in-person meeting by providing for, among other things, the ability of stockholders to submit appropriate questions in advance of the meeting to ensure thoughtful responses from management and our board of directors.

How do I vote and what are the voting deadlines?

Stockholders of Record. If you are a stockholder of record, you can vote in one of the following ways:

Even if you plan to attend the Annual Meeting, we recommend that you also vote by proxy so that your vote will be counted if you later decide not to attend the Annual Meeting.

Street Name Stockholders. If you are the beneficial owner of shares held of record by a broker, bank or other nominee, you will receive voting instructions from your broker, bank or other nominee. You must follow the voting instructions provided by your broker, bank or other nominee in order to instruct your broker, bank or other nominee how to vote your shares. The availability of Internet and telephone voting options will depend on the voting process of your broker, bank or other nominee. As discussed above, if you are a street name stockholder, you may not vote your shares live at the Annual Meeting unless you obtain a legal proxy from your broker, bank or other nominee.

Can I change my vote or revoke my proxy?

Stockholders of Record. If you are a stockholder of record, you may revoke your proxy or change your proxy instructions at any time before your proxy is voted at the Annual Meeting by:

Street Name Stockholders. If you are a street name stockholder, you must contact the broker, bank or other nominee holding your shares and follow their instructions to change your vote or revoke your proxy.

What is the effect of giving a proxy?

Proxies are solicited by and on behalf of our board of directors. Jason Lettmann and Harish Shantharam have been designated as proxy holders by our board of directors. When a proxy is properly dated, executed and returned, the shares represented by such proxy will be voted at the Annual Meeting in accordance with the instructions of the stockholder. If the proxy is dated and signed, but no specific instructions are given, the shares will be voted in accordance with the recommendations of our board of directors. If any matters not described in this proxy statement are properly presented at the Annual Meeting, the proxy holders will use their own judgment to determine how to vote your shares. If the Annual Meeting is postponed or adjourned, the proxy holders can vote your shares on the new meeting date, unless you have properly revoked your proxy, as described above.

What if I do not specify how my shares are to be voted?

Stockholders of Record. If you are a stockholder of record and you submit a proxy but you do not provide voting instructions, your shares will be voted:

Street Name Stockholders. If you are a street name stockholder and you do not provide your broker, bank or other nominee that holds your shares with voting instructions, then your broker, bank or other nominee will determine if it has discretion to vote on each matter. Brokers do not have discretion to vote on non-routine matters. Proposal No. 1 (election of directors) and Proposal No. 2 (approval, on an advisory basis, of the compensation of our named executive officers) are non-routine matters, while Proposal No. 3 (ratification of the appointment of our independent registered public accounting firm) is a routine matter. As a result, if you do not provide voting instructions to your broker, bank or other nominee, then your broker, bank or other nominee may not vote your shares with respect to Proposal No. 1 or Proposal No. 2, which would result in a “broker non-vote,” but may, in its discretion, vote your shares with respect to Proposal No. 3. For additional information regarding broker non-votes, see “—What are the effects of abstentions and broker non-votes?” below.

What are the effects of abstentions and broker non-votes?

An abstention represents a stockholder’s affirmative choice to decline to vote on a proposal. If a stockholder indicates on its proxy card that it wishes to abstain from voting its shares, or if a broker, bank or other nominee holding its customers’ shares of record causes abstentions to be recorded for shares, these shares will be considered present and entitled to vote at the Annual Meeting. As a result, abstentions will be counted for purposes of determining the presence or absence of a quorum and will also count as votes against a proposal in cases where approval of the proposal requires the affirmative vote of a majority of the shares present and entitled to vote at the Annual Meeting (e.g., Proposal No. 2 and Proposal No. 3). However, because the outcome of Proposal No. 1 (election of directors) will be determined by a plurality vote, abstentions will have no impact on the outcome of such proposal as long as a quorum exists.

A broker non-vote occurs when a broker, bank or other nominee holding shares for a beneficial owner does not vote on a particular proposal because the broker, bank or other nominee does not have discretionary voting power with respect to such proposal and has not received voting instructions from the beneficial owner of the shares. Broker non-votes will be counted for purposes of calculating whether a quorum is present at the Annual Meeting but will not be counted for purposes of determining the number of votes cast. Therefore, a broker non-vote will make a quorum more readily attainable but will not otherwise affect the outcome of the vote on any proposal.

How are proxies solicited for the Annual Meeting and who is paying for such solicitation?

Our board of directors is soliciting proxies for use at the Annual Meeting by means of the proxy materials. We will bear the entire cost of proxy solicitation, including the preparation, assembly, printing, mailing and distribution of the proxy materials. Copies of solicitation materials will also be made available upon request to brokers, banks and other nominees to forward to the beneficial owners of the shares held of record by such brokers, banks or other nominees. The original solicitation of proxies may be supplemented by solicitation by telephone, electronic communication or other means by our directors, officers, employees or agents. No additional compensation will be paid to these individuals for any such services, although we may reimburse such individuals for their reasonable out-of-pocket expenses in connection with such solicitation. We do not plan to retain a proxy solicitor to assist in the solicitation of proxies.

If you choose to access the proxy materials and/or vote over the Internet, you are responsible for Internet access charges you may incur. If you choose to vote by telephone, you are responsible for telephone charges you may incur.

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

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

Is my vote confidential?

Proxy instructions, ballots and voting tabulations that identify individual stockholders are handled in a manner that protects your voting privacy. Your vote will not be disclosed either within the Company or to third parties, except as necessary to meet applicable legal requirements, to allow for the tabulation of votes and certification of the vote, or to facilitate a successful proxy solicitation.

I share an address with another stockholder, and we received only one paper copy of the proxy materials. How may I obtain an additional copy of the proxy materials?

We have adopted a procedure approved by the SEC called “householding,” under which we can deliver a single copy of the proxy materials and Annual Report to multiple stockholders who share the same address unless we received contrary instructions from one or more of the stockholders. This procedure reduces our printing and mailing costs. Stockholders who participate in householding will continue to be able to access and receive separate proxy cards. Upon written or oral request, we will promptly deliver a separate copy of the proxy materials and Annual Report to any stockholder at a shared address to which we delivered a single copy of any of these documents. To receive a separate copy, or, if you are receiving multiple copies, to request that we only send a single copy of next year’s proxy materials and Annual Report, you may contact us as follows:

ALX Oncology Holdings Inc.

Attention: Secretary

323 Allerton Avenue

South San Francisco, California 94080

(650) 466-7125

Stockholders who hold shares in street name may contact their brokerage firm, bank, broker-dealer or other nominee to request information about householding.

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

We will announce preliminary voting results at the Annual Meeting. In addition, we intend to disclose final voting results on a Current Report on Form 8-K that we expect to file within four business days after the Annual Meeting.

What is the deadline to propose actions for consideration at next year’s annual meeting of stockholders or to nominate individuals to serve as directors?

Stockholder Proposals or Director Nominations

Stockholders may present proper proposals for inclusion in our proxy statement and for consideration at next year’s annual meeting of stockholders by submitting their proposals in writing to our Secretary in a timely manner. For a stockholder proposal to be considered for inclusion in our proxy statement for our 2027 annual meeting of stockholders, our Secretary must receive the written proposal at our principal executive offices not later than December 21, 2026. In addition, stockholder proposals must comply with the requirements of Rule 14a-8 under the Securities Exchange Act of 1934, as amended (the Exchange Act), regarding the inclusion of stockholder proposals in company-sponsored proxy materials. Stockholder proposals should be addressed to:

ALX Oncology Holdings Inc.

Attention: Secretary

323 Allerton Avenue

South San Francisco, California 94080

Our Bylaws also establish an advance notice procedure for stockholders who wish to present a proposal or nominate a director at an annual meeting of stockholders but do not intend for the proposal or director nominee to be included in our proxy statement. In addition to satisfying the requirements of our Bylaws, shareholders who intend to nominate directors other than the directors we have nominated must also comply with the additional requirements of Rule 14a-19 under the Exchange Act. Our Bylaws provide that the only business that may be conducted at an annual meeting is business that is (i) specified in our

proxy materials with respect to such meeting, (ii) otherwise properly brought before the annual meeting by or at the direction of the our board of directors, or (iii) properly brought before the annual meeting by a stockholder of record entitled to vote at the annual meeting who has delivered timely written notice to our Secretary, which notice must contain the information specified in our Bylaws. To be timely for our 2027 annual meeting of stockholders, our Secretary must receive the written notice at our principal executive offices:

In the event that we hold our 2027 annual meeting of stockholders more than 25 days before or more than 25 days after the first anniversary of the date of the Annual Meeting, then notice of a stockholder proposal that is not intended to be included in our proxy statement must be received no earlier than 5:00 p.m. Pacific Time on the 120th day before such annual meeting and no later than 5:00 p.m. Pacific Time on the later of the following two dates:

If a stockholder who has notified us of their intention to present a proposal at an annual meeting does not appear to present their proposal at such annual meeting, we are not required to present the proposal for a vote at such annual meeting.

Availability of Bylaws

A copy of our Bylaws may be obtained by accessing our public filings on the SEC’s website at http://www.sec.gov. You may also contact our Secretary at our principal executive office for a copy of the relevant provisions in our Bylaws regarding the requirements for making stockholder proposals and nominating director candidates.

BOARD OF DIRECTORS AND CORPORATE GOVERNANCE

Our business affairs are managed under the direction of our board of directors, which currently consists of seven members. Our board of directors has affirmatively determined that five of our seven directors qualify as “independent” within the meaning of the listing standards of the Nasdaq Stock Market LLC. Our board of directors is divided into three classes with staggered three-year terms. At each annual meeting of stockholders, a class of director(s) will be elected for a three-year term to succeed the same class whose term is then expiring.

Upon the recommendation of our corporate governance and nominating committee, we are nominating Daniel Curran, M.D., Rekha Hemrajani and Chris Takimoto, M.D., Ph.D., F.A.C.P., as Class III directors at the Annual Meeting. If elected, Drs. Curran and Takimoto and Ms. Hemrajani will each hold office for a three-year term until the annual meeting of stockholders to be held in 2029 or until their successors are duly elected and qualified.

The following table sets forth the names, ages and certain other information, including the composition of the committees, as of the date of this proxy statement, for each of the directors with terms expiring at the Annual Meeting (who are also nominees for election as a director at the Annual Meeting), and for each of the continuing directors:

Director Nominees

Daniel Curran, M.D. has served as a member of our board of directors since August 2025. Dr. Curran currently serves as the chief executive officer of Timberlyne Therapeutics, a clinical-stage biopharmaceutical company, since January 2025, and has served as a managing partner at Mountainfield Venture Partners, LLC, a company-creation firm since March 2024. From 2008 to 2023, Dr. Curran has held roles of increasing responsibility at Takeda Pharmaceutical Company Ltd., and most recently served as a senior vice president and the head of the rare genetics and hematology therapeutic area unit from January 2019 to December 2023. Before Dr. Curran joined Takeda, he served as vice president, corporate development at Millennium Pharmaceuticals, Inc., from 1999 to 2008. Prior to joining Millennium, Dr. Curran held a business development role in the product planning and acquisition group at DuPont Merck Pharmaceuticals, a pharmaceutical company. Dr. Curran currently serves on the board of directors of Catalyst Pharmaceuticals, Inc., a commercial-stage biopharmaceutical public company, since August 2025 and on the board of directors of Xilio Therapeutics, Inc., a clinical stage biotechnology public company,

since December 2020. In addition, Dr. Curran previously served on the board of directors of Tome Biosciences, a private biotechnology company, from January 2024 to November 2024 and also served on the board of directors of Oak Hill Biosciences, a private biotechnology company, from April 2022 to March 2024. Dr. Curran holds a B.S. in chemistry from King’s College, an M.B.A. from The Wharton School of the University of Pennsylvania and an M.D. from the University of Pennsylvania School of Medicine.

We believe that Dr. Curran is qualified to serve on our board of directors due to his more than 25 years of experience in the pharmaceutical industry, with deep expertise in research, development, strategy and business development.

Rekha Hemrajani has served as a member of our board of directors since April 2020. Ms. Hemrajani served as Chief Executive Officer and Director of Jiya Acquisition Corporation from August 2020 to November 2022. She previously served as President and Chief Executive Officer of Aravive, Inc., a clinical-stage biotechnology company, from January 2020 to April 2020. From March 2019 to September 2019, Ms. Hemrajani served as the Chief Operating Officer and Chief Financial Officer of Arcus Biosciences, a biotechnology company. From March 2016 to March 2019, she served as Chief Operating Officer of RAPT Therapeutics, Inc., a biotechnology company (later acquired by Glaxo SmithKline). From February 2015 to March 2016, Ms. Hemrajani served as Chief Financial Officer and Senior Vice President of Business and Financial Operations at Sagimet Biosciences, Inc., a biotechnology company. Prior to this, Ms. Hemrajani was Vice President, Head of Licensing & M&A at Onyx Pharmaceuticals (acquired by Amgen), in business development roles at Exelixis Inc. and in healthcare investment banking at Credit Suisse First Boston and Lehman Brothers where she advised companies on capital raising, mergers and acquisitions. She currently serves as a director of LB Pharmaceuticals Inc., a biopharmaceutical company since September 2025, BioAge Labs, Inc., a biopharmaceutical company since August 2021, and MaxCyte, Inc., a provider of cell-engineering platform technologies since June 2021, and previously served as a director of Adverum Biotechnologies, Inc. from May 2019 to April 2021, and Jiya Acquisition Corp. from August 2020 to November 2022. Ms. Hemrajani holds a B.S. in Economics and Computer Science from the University of Michigan and an M.B.A. from the Kellogg Graduate School of Management at Northwestern University.

We believe Ms. Hemrajani is qualified to serve on our board of directors due to her executive and financial experience at multiple companies in the biopharmaceutical and biotechnology industries.

Chris Takimoto, M.D., Ph.D., F.A.C.P. has served as a member of our board of directors since January 2025. Dr. Takimoto has served as the Chief Medical Officer of the START Center for Cancer Research, a global network of specialized early phase oncology clinical trial sites since October 2024. He previously served as the Chief Medical Officer of IGM Biosciences, Inc., a clinical-stage biotechnology company, or IGM, from July 2021 to October 2024. Prior to joining IGM, Dr. Takimoto served as Senior Vice President, Oncology at Gilead Sciences from April 2020 to July 2021. From February 2016 to April 2020, Dr. Takimoto served as the Chief Medical Officer of Forty Seven, Inc. until Gilead Sciences acquired Forty Seven. Dr. Takimoto previously held various leadership positions at biotechnology companies including Janssen Research Development and Ortho Biotech Oncology Research and Development and multiple positions at academic institutions such as the University of Texas Health Science Center, the National Cancer Institute, and the Uniformed Services University of the Health Sciences. Dr. Takimoto has also served as a Commissioned Officer in the U.S. Public Health Service. Dr. Takimoto holds a B.S. in Chemistry from Stanford University, a Ph.D. in Pharmacology from Yale University, and an M.D. from Yale University School of Medicine.

We believe Dr. Takimoto’s experience in the biotechnology industry qualifies him to serve on our board of directors.

Continuing Directors

Corey Goodman, Ph.D. is our co-founder and has served as a member of our board of directors and as Chairman since March 2015. He co-founded and has served as a Managing Partner of venBio Partners since March 2010. Dr. Goodman founded Labrys, a biopharmaceutical company acquired by Teva, where he served as chairman and as a member of the board of directors from December 2012 to June 2014. He founded Pfizer’s Biotherapeutics and Bioinnovation Center where he served as President and a member of Pfizer’s Executive Leadership Team from October 2007 until May 2009. He co-founded Renovis, a biopharmaceutical company acquired by Evotec, where he served as President, Chief Executive Officer and a director from September 2001 to October 2007. He is a former tenured biology professor at both Stanford University and the University of California, Berkeley, the co-founder of U.C. Berkeley’s Wills Neuroscience Institute, Investigator with the Howard Hughes Medical Institute and currently is an adjunct professor at U.C. Berkeley. Dr. Goodman is a member of the U.S. National Academy of Sciences, the American Academy of Arts & Sciences and the American Philosophical Society and a recipient of the 2020 Gruber Neuroscience Prize. He currently serves as chairman and as a member of the board of directors of several privately held biotechnology companies. Dr. Goodman holds a B.S. in Biology from Stanford University and a Ph.D. in Neurobiology from U.C. Berkeley and was a postdoctoral fellow at U.C. San Diego.

We believe Dr. Goodman is qualified to serve on our board of directors due to his experience founding and managing biotechnology companies in both the private and public markets.

Jason Lettmann has served as our Chief Executive Officer since September 2023, as a member of our board of directors since April 2020 and previously served as a member of our board of directors from March 2015 to May 2017. Mr. Lettmann has served as a Partner at Morgenthaler Ventures, a venture capital and private equity firm, since June 2009, and served as a General Partner of Lightstone Ventures from March 2012 to July 2023. He previously served as Chief Executive Officer of Promedior Inc., a biotechnology company acquired by Roche, from January 2019 to February 2020 and as a Vice President at Split Rock Partners, a venture capital firm, from June 2006 to June 2009. Mr. Lettmann currently serves as a member of the board of directors of several privately-held companies and previously served as a director of Ra Pharmaceuticals, a clinical-stage pharmaceutical company acquired by UCB. Mr. Lettmann holds a B.A. in Psychology from the University of Iowa and an M.B.A. from the University of Michigan’s Ross School of Business.

We believe Mr. Lettmann is qualified to serve on our board of directors because of the perspective and experience he brings as our chief executive officer, his industry experience, his experience serving on the boards of directors for multiple life sciences companies and his extensive experience with venture capital investments.

Scott Garland has served as a member of our board of directors since November 2022. Mr. Garland served as the Chief Executive Officer of PACT Pharma, Inc., an immuno-oncology company, from March 2021 to February 2023. He previously served as President, Chief Executive Officer and a member of the board of Portola Pharmaceuticals, Inc., a biopharmaceutical company, from October 2018 until July 2020 when it was acquired by Alexion Pharmaceuticals, Inc. From April 2017 to September 2018, Mr. Garland served as President of Relypsa Inc., a biopharmaceutical company, and as Senior Vice President and Chief Commercial Officer from October 2014 to April 2017. From October 2011 to October 2014, he served as Executive Vice President and Chief Commercial Officer of Exelixis, Inc., a biopharmaceutical company focused on developing and commercializing cancer treatments. Mr. Garland currently serves as a member of the board of directors of Day One Pharmaceuticals, Inc., Enliven Therapeutics, Inc., LB Pharmaceuticals Inc., Olema Pharmaceuticals, Inc. and Hexagon Bio, a private-held company, and previously served on the board of directors of Karyopharm Therapeutics Inc. and Calithera

Biosciences Inc. He holds a B.S. in Biological Sciences from California Polytechnic State University (San Luis Obispo) and an M.B.A. from Duke University’s Fuqua School of Business.

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

Alan Sandler, M.D. has served as a member of our board of directors since September 2025 and previously served as our Chief Medical Officer from November 2024 until September 2025 and as a member of our board of directors from August 2024 until November 2024. He has served as the Chief Development Officer at Revolution Medicines Inc., a biotechnology company, since September 2025. Dr, Sandler also serves as a member of the scientific advisory boards of TOLREMO therapeutics AG and Avidicure, strategic advisory board for N-Power Medicine and served as a member of the board of directors of Elevation Oncology, Inc. from March 2024 to July 2025. He served as Executive Vice President and Chief Medical Officer of Mirati Therapeutics, prior to and through its acquisition by Bristol Myers Squibb, from November 2022 to April 2024. Prior to joining Mirati Therapeutics, he was the President, Head of Global Development, Oncology at Zai Lab Limited from December 2020 to October 2022. Prior to that, Dr. Sandler held roles of increasing responsibility at Genentech, a biotechnology company and member of the Roche Group, from July 2013 to November 2020, culminating in his final role as Senior Vice President, Global Head of Product Development, Oncology. He holds a B.S. in Pharmacy from the University of Toledo and an M.D. from Rush Medical School.

We believe Dr. Sandler’s decades of oncology and drug development experience qualify him to serve on our board of directors.

Family Relationships

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

Director Independence

Our common stock is listed on the Nasdaq Global Select Market (Nasdaq). Under the rules of Nasdaq, independent directors must comprise a majority of a listed company’s board of directors within one year of the completion of its initial public offering. In addition, the rules of Nasdaq require that, subject to specified exceptions, each member of a listed company’s audit, compensation and corporate governance and nominating committees be independent. Audit committee members and compensation committee members must also satisfy the independence criteria set forth in Rule 10A-3 and Rule 10C-1, respectively, under the Exchange Act. Under the rules of Nasdaq, a director will only qualify as an “independent director” if, in the opinion of that company’s board of directors, that person does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director.

To be considered to be independent for purposes of Rule 10A-3 and under the rules of Nasdaq, a member of an audit committee of a listed company may not, other than in his or her capacity as a member of the audit committee, the board of directors or any other board committee: (1) accept, directly or indirectly, any consulting, advisory or other compensatory fee from the listed company or any of its subsidiaries or (2) be an affiliated person of the listed company or any of its subsidiaries.

To be considered independent for purposes of Rule 10C-1 and under the rules of Nasdaq, the board of directors must affirmatively determine that each member of the compensation committee is independent, including a consideration of all factors specifically relevant to determining whether the director has a relationship to the company which is material to that director’s ability to be independent from management in connection with the duties of a compensation committee member, including, but not limited to: (1) the

source of compensation of such director, including any consulting, advisory or other compensatory fee paid by the company to such director and (2) whether such director is affiliated with the company, a subsidiary of the company or an affiliate of a subsidiary of the company.

Our board of directors undertook a review of its composition, the composition of its committees and the independence of our directors and considered whether any director has a material relationship with us that could compromise his or her ability to exercise independent judgment in carrying out his or her responsibilities. Based upon information requested from and provided by each director concerning his background, employment and affiliations, including family relationships, our board of directors has determined that Drs. Curran, Goodman and Takimoto, Mr. Garland and Ms. Hemrajani, representing five of our seven directors, do not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director and that each of these directors is “independent” as that term is defined under the rules of Nasdaq.

In making these determinations, our board of directors considered the current and prior relationships that each non-employee director has with our company and all other facts and circumstances our board of directors deemed relevant in determining their independence, including the beneficial ownership of our capital stock by each non-employee director, and the transactions involving them described in the section titled “Certain Relationships and Related-Party Transactions.”

Board Leadership Structure

Our board of directors is currently chaired by Dr. Goodman. As a general policy, our board of directors believes that separation of the positions of Chairman of our board of directors and Chief Executive Officer reinforces the independence of our board of directors from management, creates an environment that encourages objective oversight of management’s performance and enhances the effectiveness of our board of directors as a whole. As such, Mr. Lettmann serves as our Chief Executive Officer while Dr. Goodman serves as the Chairman of our board of directors and is not an officer of the company. We currently expect and intend the positions of Chairman of our board of directors and Chief Executive Officer to continue to be held by two individuals in the future.

Board Diversity

The corporate governance and nominating committee is committed to continuing to identify and recruit highly qualified director candidates with diverse experiences, perspectives, and backgrounds to join our board of directors. We believe the current composition of our board of directors reflects this commitment.

Role of the Board in Risk Oversight

Our board of directors has an active role, as a whole and also at the committee level, in overseeing the management of our risks. Our board of directors is responsible for general oversight of risks and regular review of information regarding our risks, including credit risks, liquidity risks and operational risks. The compensation committee is responsible for overseeing the management of risks relating to our executive compensation plans and arrangements. The audit committee is responsible for overseeing the management of risks relating to accounting matters and financial reporting and cybersecurity risks. The corporate governance and nominating committee is responsible for overseeing the management of risks associated with the independence of our board of directors and potential conflicts of interest. Although each committee is responsible for evaluating certain risks and overseeing the management of such risks, our entire board of directors is regularly informed through discussions from committee members about such risks. Our board of directors believes its administration of its risk oversight function has not negatively affected the board of directors’ leadership structure.

Committees of our Board of Directors

Our board of directors has established an audit committee, a compensation committee, and a corporate governance and nominating committee. The composition and responsibilities of each of the committees of our board of directors are described below. Members serve on these committees until their resignation or until otherwise determined by our board of directors. Our board of directors may establish other committees as it deems necessary or appropriate from time to time.

Audit Committee

Our audit committee consists of Ms. Hemrajani, Dr. Curran, and Mr. Garland. Ms. Hemrajani is the chair of our audit committee and is our audit committee financial expert, as that term is defined under the SEC rules implementing Section 407 of Sarbanes-Oxley Act of 2002, and possesses financial sophistication, as defined under the rules of Nasdaq. Our board of directors has determined that each of the members of our audit committee satisfies the independence requirements under the listing standards of Nasdaq and Rule 10A-3 of the Exchange Act. Our audit committee oversees our corporate accounting and financial reporting process and assists our board of directors in monitoring our financial systems. Our audit committee also:

Our audit committee operates under a written charter that satisfies the applicable rules and regulations of the SEC and the listing standards of Nasdaq. A copy of the charter for our audit committee is available on our investor relations website at https://ir.alxoncology.com/. During 2025, our audit committee held four meetings.

Compensation Committee

Our compensation committee consists of Drs. Goodman and Takimoto and Mr. Garland. Dr. Goodman is the chair of our compensation committee. Our board of directors has determined that each of the members of our compensation committee is independent under the listing standards of Nasdaq and a “non-employee director” as defined in Rule 16b-3 under the Exchange Act. Our compensation committee oversees our compensation policies, plans, and benefits programs. The compensation committee also:

Our compensation committee operates under a written charter that satisfies the applicable rules and regulations of the SEC and the listing standards of Nasdaq. A copy of the charter for our compensation committee is available on our investor relations website at https://ir.alxoncology.com/. During 2025, our compensation committee held five meetings.

Corporate Governance and Nominating Committee

Our corporate governance and nominating committee currently consists of Mr. Garland, Dr. Curran, and Ms. Hemrajani. Mr. Garland is the chair of our corporate governance and nominating committee. Our board of directors has determined that each member of our corporate governance and nominating committee is independent under the listing standards of Nasdaq.

Our corporate governance and nominating committee oversees and assists our board of directors in reviewing and recommending nominees for election as directors. Specifically, the corporate governance and nominating committee:

Our corporate governance and nominating committee operates under a written charter that satisfies the listing standards of Nasdaq. A copy of the charter for our corporate governance and nominating committee is available on our investor relations website at https://ir.alxoncology.com/. During 2025, our corporate governance and nominating committee held one official meeting and met numerous times on an ad hoc basis while recruiting candidates for our board of directors.

Attendance at Board and Stockholder Meetings

During our fiscal year ended December 31, 2025, our board of directors held eight meetings (including regularly scheduled and special meetings), and each director attended at least 75% of the aggregate of (i) the total number of meetings of our board of directors held during the period for which they have been a director and (ii) the total number of meetings held by all committees of our board of directors on which they served during the periods that they served on such committee.

Although we do not have a formal policy regarding attendance by members of our board of directors at annual meetings of stockholders, we strongly encourage, but do not require, our directors to attend. All of our then-current directors attended our 2025 annual meeting of stockholders.

Considerations in Evaluating Director Nominees

Our corporate governance and nominating committee uses a variety of methods, including engaging the services of outside consultants and search firms, to identify and evaluate director nominees. We have in the past used a search firm to identify, interview and screen director nominee candidates and conduct background and reference checks. In its evaluation of director candidates, our corporate governance and nominating committee will consider the current size and composition of our board of directors and the needs of our board of directors and the respective committees of our board of directors. Some of the qualifications that our corporate governance and nominating committee considers include such factors as character, integrity, judgment, independence, skills, education, expertise, business acumen, corporate experience, length of service, understanding of our business and other commitments, among other things. Nominees must also have the highest personal and professional ethics and integrity and skills that are complementary to those of the existing directors. Director candidates must have the ability to assist and support management and make significant contributions to our success based on proven achievement and competence in the nominee’s field and the ability to exercise sound business judgment. Nominees must also have an understanding of the fiduciary responsibilities that are required of a member of our board of directors and the commitment of time and energy necessary to diligently carry out those responsibilities. Members of our board of directors are expected to prepare for, attend and participate in all board of directors and applicable committee meetings. Our corporate governance and nominating committee may also consider such other factors as it may deem, from time to time, are in our and our stockholders’ best interests.

The corporate governance and nominating committee considers the suitability of each director candidate, including current directors, in light of the current size and composition of our board. Although our board of directors does not maintain a specific policy with respect to board diversity, our board of directors believes that our board of directors should be a diverse body, and our corporate governance and nominating committee considers a broad range of backgrounds and experiences. In making determinations regarding nominations of directors, our corporate governance and nominating committee may take into account the benefits of diverse viewpoints. Our corporate governance and nominating committee also considers these and other factors as it oversees the annual board of directors and committee evaluations. After completing its review and evaluation of director candidates, our corporate governance and nominating committee recommends to our full board of directors the director nominees for selection.

Stockholder Recommendations for Nominations to the Board of Directors

Our corporate governance and nominating committee will consider director candidates recommended by stockholders holding no less than $2,000 in market value, or 1%, of the outstanding shares of our common stock continuously for at least 12 months prior to the date of the submission of the recommendation or nomination, as long as such recommendations or nominations comply with our amended and restated certificate of incorporation, Bylaws, policies and procedures for director candidates, and applicable laws, rules and regulations, including those promulgated by the SEC. Our corporate governance and nominating committee will evaluate such recommendations in accordance with its charter, our Bylaws and our policies and procedures for director candidates, as well as the regular director nominee criteria described above. This process is designed to ensure that our board of directors includes members with diverse backgrounds, skills and experience, including appropriate financial and other expertise relevant to our business. Eligible stockholders wishing to recommend a candidate for nomination should contact our Secretary in writing. Such recommendations must include information about the candidate, including the principal occupation or employment of the candidate; a statement of support executed by the candidate acknowledging that as a director of the corporation, the nominee will owe a fiduciary duty under Delaware law with respect to the corporation and its stockholders; evidence of the recommending stockholder’s ownership of our capital stock; a description of all arrangements or understandings between the stockholder and each nominee and any other person or persons (naming such person or persons) pursuant to which the nominations are to be made by the stockholder; and any additional information required by our Bylaws and our policies and procedures for director candidates. Our corporate governance and nominating committee has discretion to decide which individuals to recommend for nomination as directors.

Communications with the Board of Directors

Interested parties wishing to communicate with non-management members of our board of directors may do so by writing and mailing the correspondence to our Secretary at ALX Oncology Holdings Inc., 323 Allerton Avenue, South San Francisco, California 94080. Our Secretary monitors these communications and will provide a summary of all received bona fide messages to our board of directors at each regularly scheduled meeting of our board of directors. Where the nature of a communication warrants, our Secretary may determine, in their judgment, to obtain the more immediate attention of the appropriate committee of the board of directors or non-management director, of independent advisors or of our management.

This procedure does not apply to (1) communications to non-management directors from officers or directors who are stockholders, (2) stockholder proposals submitted pursuant to Rule 14a-8 under the Exchange Act or (3) communications to our audit committee pursuant to our complaint procedures for accounting and auditing matters.

Corporate Governance Guidelines and Code of Business Conduct and Ethics

Our board of directors has adopted Corporate Governance Guidelines that address items such as the qualifications and responsibilities of our directors and director candidates and corporate governance policies and standards applicable to us in general. In addition, our board of directors has adopted a Code of Business Conduct and Ethics that applies to all of our employees, officers and directors, including our Chief Executive Officer, Chief Financial Officer and other executive and senior financial officers. The full text of our Corporate Governance Guidelines and our Code of Business Conduct and Ethics is posted on our investor relations website at https://ir.alxoncology.com/. We will post any amendments to our Code of Business Conduct and Ethics and any waivers of our Code of Business Conduct and Ethics for directors and executive officers on the same website or in filings under the Exchange Act.

Director Compensation

We maintain an Outside Director Compensation Policy that provides for certain compensation to our non-employee directors. Our Outside Director Compensation Policy is designed to attract, retain and reward non-employee directors. This policy is reviewed periodically by our board of directors and our compensation committee with input from our compensation committee’s independent compensation consultant, Compensia, regarding practices and compensation levels at comparable companies.

Under the Outside Director Compensation Policy, each non-employee director receives cash and equity compensation for his or her services as a member of our board of directors, as described below.

Cash Compensation

The Outside Director Compensation Policy provides for the following cash compensation program for our non-employee directors:

Each non-employee director who serves as a committee chair will receive only the cash retainer fee as the chair of the committee but not the cash retainer fee as a member of that committee. These fees to our non-employee directors are paid quarterly in arrears on a prorated basis. Under our Outside Director Compensation Policy, we also will reimburse our non-employee directors for reasonable travel expenses to attend meetings of our board of directors and its committees. In September 2025, our board of directors determined to pause the activities of the research and development committee.

Equity Compensation

Initial Award. Pursuant to our Outside Director Compensation Policy, each person who first becomes a non-employee director after the effective date of such policy will receive, on the first trading day on or after the date that the person first becomes a non-employee director, an initial award, or the Initial Award, of stock options to purchase 40,400 shares of our common stock. The Initial Award will be scheduled to vest in equal installments as to one thirty-sixth of the shares of our common stock subject at grant to the Initial Award on a monthly basis following the Initial Award’s grant date, on the same day of the month as the grant date, subject to continued services to us through the applicable vesting dates. If the person was a member of our board of directors and also an employee, then becoming a non-employee director due to termination of employment will not entitle the person to an Initial Award.

Annual Award. Pursuant to our Outside Director Compensation Policy, each non-employee director automatically will receive, on the first trading day on or after January 20 of each year, an Annual Award of stock options to purchase 40,400 shares of our common stock, with such number of shares prorated if the recipient commenced service as a non-employee director after the first trading day on or after January 20 of the immediately preceding year, based on the number of whole months of non-employee director service completed before the Annual Award’s grant date. Each Annual Award will be scheduled to vest as to one-twelfth of the shares of our common stock subject at grant to the Annual Award on a monthly basis following the Annual Award’s grant date, on the same day of the month as the grant date, or if earlier, the day immediately before the day of the next annual meeting of stockholders that occurs after the grant date of the Annual Award, subject to continued services to us through the applicable vesting dates.

Change in Control. In the event of a change in control, as defined in our Amended and Restated 2020 Equity Incentive Plan (2020 Plan), each non-employee director’s then outstanding equity awards covering shares of our common stock will accelerate vesting in full, provided that he or she remains a non-employee director through the date of our change in control.

Other Award Terms. Each Initial Award and Annual Award will be granted under our 2020 Plan (or its successor plan, as applicable) and form of award agreement under such plan. These awards will have a maximum term to expiration of ten years from their grant and a per-share exercise price equal to 100% of the fair market value of a share of our common stock on the award’s grant date.

Director Compensation Limits. Our Outside Director Compensation Policy and our 2020 Plan provide that in any fiscal year, a non-employee director may be paid cash compensation and granted equity awards with an aggregate value of no more than $1,000,000 (with the value of equity awards based on its grant date fair value determined in accordance with U.S. GAAP for purposes of this limit). Equity awards granted or other compensation provided to a non-employee director while he or she was an employee or consultant (other than a non-employee director), or granted or provided before the effective date of the registration statement related to our initial public offering, do not count toward this annual limit.

2025 Compensation

Directors who are also our employees receive no additional compensation for their service as directors. During 2025, Mr. Lettmann was an employee and executive officer of the Company and did not receive compensation as director. See the section titled “Executive Compensation” for additional information about Mr. Lettmann’s compensation for the year ended December 31, 2025.

The following table presents the total compensation of each of our non-employee directors received during the year ended December 31, 2025. Other than as set forth in the table, we did not pay any compensation, make any equity awards or non-equity awards to or pay any other compensation to any of our non-employee directors in 2025.

Director Compensation for Fiscal Year 2025

The following table lists all outstanding equity awards held by non-employee directors as of December 31, 2025:

PROPOSAL NO. 1

ELECTION OF DIRECTORS

Our board of directors is currently composed of seven members. In accordance with our amended and restated certificate of incorporation, our board of directors is divided into three classes with staggered three-year terms. At the Annual Meeting, three Class III directors will be elected for a three-year term to succeed the same class whose term is then expiring.

Each director’s term continues until the election and qualification of such director’s successor, or such director’s earlier death, resignation or removal. Any increase or decrease in the number of directors will be distributed among the three classes so that, as nearly as possible, each class will consist of one-third of our directors. This classification of our board of directors may have the effect of delaying or preventing changes in control of our company.

Nominees

Our corporate governance and nominating committee has recommended, and our board of directors has approved, Daniel Curran, M.D., Rekha Hemrajani and Chris Takimoto, M.D., Ph.D., F.A.C.P., as nominees for election as Class III directors at the Annual Meeting. If elected, each of Drs. Curran and Takimoto and Ms. Hemrajani will serve as a Class III director until the 2029 annual meeting of stockholders or until his or her successor is duly elected and qualified. Drs. Curran and Takimoto and Ms. Hemrajani are currently directors of our company, and each has agreed to being named in this proxy statement as a nominee. For information concerning the nominees, please see the section titled “Board of Directors and Corporate Governance.”

If you are a stockholder of record and you sign your proxy card or vote over the Internet or by telephone but do not give instructions with respect to the voting of directors, your shares will be voted FOR the election of Drs. Curran and Takimoto and Ms. Hemrajani. If you are a street name stockholder of shares of our common stock and you do not give voting instructions to your broker, bank or other nominee, then your broker, bank or other nominee will leave your shares unvoted on this matter. We expect that Drs. Curran and Takimoto and Ms. Hemrajani will accept such nomination; however, in the event that a director nominee is unable or declines to serve as a director at the time of the Annual Meeting, the proxies will be voted for any nominee who shall be designated by our board of directors to fill such vacancy.

Vote Required

The election of Class III directors requires a plurality of the votes of the shares of our common stock present in person (including virtually) or represented by proxy at the Annual Meeting and entitled to vote thereon to be approved. “Plurality” means that the three nominees who receive the most votes cast ‘FOR’ will be elected as Class III directors. As a result, any shares not voted ‘FOR’ a particular nominee (whether as a result of voting withheld or a broker non-vote) will not be counted in such nominee’s favor and will have no effect on the outcome of the election.

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE ELECTION OF EACH OF THE THREE NOMINEES NAMED ABOVE AS CLASS III DIRECTORS TO SERVE FOR A THREE-YEAR TERM.

PROPOSAL NO. 2

ADVISORY VOTE ON THE COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS

This stockholder advisory vote, commonly known as “say-on-pay,” is required pursuant to Section 14A of the Exchange Act and gives our stockholders the opportunity to approve or not approve, on a non-binding advisory basis, the compensation paid to our Chief Executive Officer and the other executive officers named in the Summary Compensation Table (named executive officers) as disclosed in this proxy statement.

The Board recommends a vote “FOR” the following resolution:

“RESOLVED, that the stockholders of ALX Oncology Holdings Inc. approve, on an advisory basis, the compensation of the named executive officers, as disclosed in the proxy statement pursuant to Item 402 of Regulation S-K, including the compensation tables and any related narrative discussion.”

We became a public company in July 2020 and since that time we have made important changes to our executive compensation program to reflect our transition from a private to public company. In 2025, our stockholders approved the “say-on-pay” vote with 68.64% of the shares of our common stock present and entitled to vote in support of our named executive officer compensation as disclosed in our 2025 proxy statement. In 2022, we held our first Say-on-Pay vote and each year we intend to submit the executive compensation of our named executive officers to an advisory vote at our annual meeting of stockholders, consistent with the “say-when-on-pay” recommendation from our stockholders at our 2022 annual meeting, until such time as the say-when-on-pay proposal is brought before our stockholders again.

Our board of directors is asking you to support this proposal. Because this vote is advisory, it will not be binding on us, our compensation committee or our board of directors. However, our compensation committee and our board of directors will review the voting results in their entirety and take them into consideration when making future decisions regarding named executive officer compensation.

Vote Required

The approval, on an advisory basis, of the compensation of our named executive officers requires an affirmative vote of a majority of the shares of our common stock present in person (including virtually) or represented by proxy at the Annual Meeting and entitled to vote thereon. Abstention will have the same effect as a vote AGAINST the proposal, and broker non-votes will have no effect.
 

OUR BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR”

THE APPROVAL OF THE COMPENSATION OF OUR NAMED EXECUTIVE OFFICERS AS DISCLOSED IN THE PROXY STATEMENT.

PROPOSAL NO. 3

RATIFICATION OF APPOINTMENT OF

INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Our audit committee has appointed KPMG LLP, an independent registered public accounting firm, to audit our consolidated financial statements for our fiscal year ending December 31, 2026. KPMG LLP has served as our independent registered public accounting firm since 2016.

At the Annual Meeting, our stockholders are being asked to ratify the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2026. Stockholder ratification of the appointment of KPMG LLP is not required by our Bylaws or other applicable legal requirements. However, our board of directors is submitting the appointment of KPMG LLP to our stockholders for ratification as a matter of good corporate governance. In the event that this appointment is not ratified by the affirmative vote of a majority of the shares present in person (including virtually) or represented by proxy at the Annual Meeting and entitled to vote, such appointment will be reconsidered by our audit committee. Even if the appointment is ratified, our audit committee, in its sole discretion, may appoint another independent registered public accounting firm at any time during our fiscal year ending December 31, 2026 if our audit committee believes that such a change would be in the best interests our company and our stockholders. A representative of KPMG LLP is expected to be present at the Annual Meeting, will have an opportunity to make a statement if they wish to do so, and is expected to be available to respond to appropriate questions from stockholders.

Fees Paid to the Independent Registered Public Accounting Firm

The following table presents fees for professional audit services and other services rendered to us by KPMG LLP for our fiscal years ended December 31, 2025 and 2024.

Auditor Independence

In our fiscal year ended December 31, 2025, there were no other professional services provided by KPMG LLP that would have required our audit committee to consider their compatibility with maintaining the independence of KPMG LLP.

Audit Committee Policy on Pre-Approval of Audit and Permissible Non-Audit Services of Independent Registered Public Accounting Firm

Our audit committee has established a policy governing our use of the services of our independent registered public accounting firm. Under the policy, our audit committee is required to pre-approve all audit and permissible non-audit services performed by our independent registered public accounting firm in order to ensure that the provision of such services does not impair such accounting firm’s independence. All services provided by KPMG LLP for our fiscal years ended December 31, 2025 and 2024 were pre-approved by our audit committee.

Vote Required

The ratification of the appointment of KPMG LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2026 requires the affirmative vote of a majority of the shares of our common stock present in person (including virtually) or represented by proxy at the Annual Meeting and entitled to vote thereon. Abstentions will have the effect of a vote AGAINST this proposal, and broker non-votes will have no effect.

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE RATIFICATION OF THE APPOINTMENT OF KPMG LLP AS OUR INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM FOR OUR FISCAL YEAR ENDING DECEMBER 31, 2026.

AUDIT COMMITTEE REPORT

The audit committee is a committee of the board of directors comprised solely of independent directors as required by the listing standards of the Nasdaq Stock Market LLC and the rules and regulations of the Securities and Exchange Commission (the SEC). The composition of the audit committee, the attributes of its members and the responsibilities of the audit committee, as reflected in its charter, are intended to be in accordance with applicable requirements for corporate audit committees. The audit committee operates under a written charter approved by the board of directors, which is available on our website at https://ir.alxoncology.com/. The audit committee reviews and assesses the adequacy of its charter and the audit committee’s performance on an annual basis.

With respect to the Company’s financial reporting process, the Company’s management is responsible for (1) establishing and maintaining internal controls and (2) preparing the Company’s consolidated financial statements. The Company’s independent registered public accounting firm, KPMG LLP (KPMG), is responsible for performing an independent audit of the Company’s consolidated financial statements. It is the responsibility of the audit committee to oversee these activities. It is not the responsibility of the audit committee to prepare the Company’s consolidated financial statements. These are the fundamental responsibilities of management.

In the performance of its oversight function, the audit committee has:

Based on the audit committee’s review and discussions with management and KPMG, the audit committee recommended to the board of directors that the audited consolidated financial statements be included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2025 for filing with the SEC.

Respectfully submitted by the members of the audit committee of the board of directors:

Rekha Hemrajani (Chair)

Daniel Curran, M.D.

Scott Garland

This report of the audit committee is required by the SEC and, in accordance with the SEC’s rules, will not be deemed to be part of or incorporated by reference by any general statement incorporating by reference this proxy statement into any filing under the Securities Act of 1933, as amended (the Securities Act), or under the Securities Exchange Act of 1934, as amended (the Exchange Act), except to the extent that we specifically incorporate this information by reference, and will not otherwise be deemed “soliciting material” or “filed” under either the Securities Act or the Exchange Act.

EXECUTIVE OFFICERS

The following table sets forth certain information about our executive officers as of April 15, 2026. Officers are elected by our board of directors to hold office until their successors are elected and qualified.

For the biography of Mr. Lettmann, please see “Board of Directors—Continuing Directors.”

Harish Shantharam has served as our Chief Financial Officer since January 2025. Prior to joining us, Mr. Shantharam served as the Chief Financial Officer of CymaBay Therapeutics, Inc., a pharmaceutical company, from May 2023 to June 2024, including through the completion of its acquisition in March 2024 by Gilead Sciences, a pharmaceutical company. He previously served as Senior Finance Consultant at Eikon Therapeutics, a biopharmaceutical company, from August 2022 to April 2023, where he worked with the Chief Financial Officer in supporting finance operations. Mr. Shantharam was employed at Gilead from October 2011 through May 2022, where he held various positions within the finance function, most recently that of Vice President, Head of Global Commercial Finance. At Gilead, Mr. Shantharam was responsible for managing Gilead’s global commercial financial operations. Prior to Gilead, Mr. Shantharam held multiple roles in commercial planning and operations at Amgen Inc., a pharmaceutical company, from February 2004. He received his M.B.A. from UCLA Anderson School of Management and is a CFA charterholder.

Shelly Wong has served as our Senior Vice President, Finance since July 2023, as Chief Accounting Officer since May 2021, as Interim Chief Financial Officer from November 2024 to January 2025 and as Vice President, Finance from May 2021 to July 2023. Prior to joining us, she was with Tizona Therapeutics, Inc. from July 2016 to April 2021, where she served most recently as Vice President of Finance and Operations from October 2020 to April 2021. Ms. Wong was the Controller at InSite Vision Inc. from December 2008 to July 2016, the Assistant Controller at Bare Escentuals, Inc. from May 2007 to November 2008, and Director of Corporate Accounting and Financial Reporting at Dreyer’s Grand Ice Cream Holdings, Inc. from March 2002 to May 2007. Ms. Wong started her career within the audit practice at Deloitte and Touche LLP after graduating with a B.S.B.A. in Accounting from Montana State University.

Barbara Klencke, M.D. has served as our Chief Medical Officer since February 2026 and previously served as our interim Chief Medical Officer from September 2025 to February 2026. She served as a member of our board of directors from January 2025 to September 2025. Dr. Klencke currently serves as a member of the board of directors of TScan Therapeutics, Inc., a biopharmaceutical company, Xencor, Inc., a biopharmaceutical company, and Immune-Onc, Inc., a privately-held biopharmaceutical company and previously served as a member of the board of directors of eFFECTOR Therapeutics, a biopharmaceutical company and Lexent Bio, Inc., a biopharmaceutical company, before that company’s acquisition by Foundation Medicine. She previously served as the Chief Medical and Chief Development Officer of Sierra Oncology, Inc., a clinical-stage biopharmaceutical company from June 2015 to December 2023 following its acquisition by GlaxoSmithKline plc in 2022. From 2011 to 2015, Dr. Klencke served as Senior Vice President, Global Development, at Onyx Pharmaceuticals, which was acquired by Amgen Inc., in 2013. Prior to joining Onyx Pharmaceuticals, she led a variety of both early- and late-stage oncology

programs while at Genentech, Inc. from 2003 to 2011. Dr. Klencke completed Internal Medicine and Hematology/Oncology training at the University of California, San Francisco and remained there as an Assistant Professor of Medicine in Oncology focusing on clinical research from 1995 to 2002. She holds a B.S. from Indiana University and an M.D. from the University of California, Davis.

Jeff Knight has served as our Chief Development and Operating Officer since April 2026. From September 2021 to April 2026, Mr. Knight was Chief Development and Operating Officer at Crinetics Pharmaceuticals, Inc., a global biopharmaceutical company. From October 2018 to August 2021, Mr. Knight served as Senior Vice President, Portfolio Management and Corporate Operations at Poseida Therapeutics, Inc., where he was responsible for portfolio management and strategy, alliance management, quality and compliance, and corporate operations. From March 2017 until October 2018, he was Vice President, Development Operations and Project and Portfolio Management at Halozyme Therapeutics, Inc. From July 2015 until March 2017, he served as Executive Director, Global Development Operations at Amgen Inc. and from January 2012 until July 2015, Mr. Knight served in various program and portfolio management and development operations roles at Onyx Pharmaceuticals. Prior to that, he held several leadership roles of increasing responsibility in clinical operations, regulatory affairs, and project management at Genentech, PRA International, and Hoechst Marion Roussel (now Sanofi). Mr. Knight earned a Master’s of Public Health in biostatistics and epidemiology from the University of Oklahoma Health Sciences Center and a B.A. in psychology from the University of Oklahoma. He also earned a B.S. in nursing from the University of Kansas.

EXECUTIVE COMPENSATION

Named Executive Officers

Our NEOs for the year ended December 31, 2025 are:

Dr. Pons served as our President and Chief Scientific Officer until April 2025.

Summary

Overview of Executive Compensation Program

Our executive compensation program is designed to be competitive and appropriately balance our goals of attracting, engaging and retaining our executive officers and driving company performance. To align our executive officers’ interests with those of our stockholders and to motivate and reward individual initiative and effort, a substantial portion of each executive officer’s total target annual direct compensation opportunity (that is, base salary, target annual cash incentives, and equity awards) is “at-risk,” meaning the amounts paid to each executive officer will vary based on our Company performance and their contributions to that performance.

Consistent with our philosophy of aligning executive pay with the short- and long-term performance of the Company, and to align the interests of management and stockholders, the Company’s compensation programs are designed to provide the majority of executive compensation in the form of variable, at-risk pay. Our compensation committee thoughtfully employs the primary compensation elements of base salary, short-term annual cash incentives, and long-term equity awards, to achieve these objectives.

Executive Compensation Governance

With guidance from an independent compensation consultant, Compensia, we maintain sound compensation and governance standards, and we adopt best practices in establishing and administering policies in support of these standards. The compensation committee evaluates our executive compensation program regularly to ensure that it supports our short-term and long-term goals to compete for executive talent as well as protect our stockholders’ interests.

Stockholder Engagement

The Company is committed to engagement with stockholders. We review any feedback we receive from our stockholders about our executive compensation program to ensure that we understand key matters of interest to them, and to enable us to take that feedback into consideration for our compensation decisions.

Compensation Philosophy

The goals of our executive compensation program are to attract, engage, and retain executive officers who share our vision and are deeply connected to our mission. Our overall compensation philosophy is market-based and enables our executive officers to share in the Company’s long-term success. We strive to incentivize these executive officers to achieve our short-term and long-term business objectives in order to increase long-term value and increase stockholder value. Our program combines competitive cash and equity award opportunities in the forms and proportions that we believe will motivate our executive officers to increase stockholder value over the long-term. We routinely review our policies and program design.

Our executive compensation program delivers rewards in line with individual and company performance using the following specific compensation methods:

“Say-on-Pay” Voting

Our compensation committee and our board of directors considers the results of the “say-on-pay” vote, as well as feedback received throughout the year, when making compensation decisions for our executive officers in the future because we value the opinions of our stockholders. In 2025 and 2024, our stockholders approved the “say-on-pay” vote with 68.64% and 96.6%, respectively, of the shares of our common stock present and entitled to vote in support of our named executive officer compensation as disclosed in our applicable proxy statements.

Compensation Determination Process

Role of Compensation Committee and Board of Directors

Our compensation committee is responsible for overseeing the total compensation of our executive officers. In this capacity, our compensation committee designs, implements, reviews, and approves all compensation for our CEO and our other executive officers. Typically, the compensation committee reports to the board of directors on its discussions and on occasion seeks input from the board of directors regarding the decisions to be made and other actions to be taken with regard to our executive officers’ compensation. Our compensation committee’s determinations regarding executive compensation are based on the compensation committee’s assessment of the performance of the Company and each individual executive officer, as well as other factors, such as prevailing industry trends and the competitive market for executive talent. The compensation committee makes the final decisions regarding executive compensation.

Role of Management

In 2025, our CEO and CFO made recommendations to our compensation committee, attended certain compensation committee meetings and were involved in the process for determining our executive officers’ compensation, provided that neither our CEO nor our CFO made recommendations as to their own compensation or participated in compensation committee deliberations and determinations of their own compensation. Our compensation committee considers management’s recommendations but is not required to follow any recommendations and may adjust compensation up or down as it determines in its discretion.

Our compensation committee reviews the recommendations and other data and makes decisions as to each executive officer’s total compensation, as well as each individual pay component.

Role of Independent Compensation Consultant

Our compensation committee is authorized to retain the services of one or more executive compensation advisors, as it sees fit, in connection with the establishment of our compensation programs and related policies. In 2025, our compensation committee retained Compensia as its independent compensation consultant to provide it with information, recommendations, and other advice relating to executive compensation on an ongoing basis. Accordingly, Compensia serves at the discretion of our compensation committee. Our compensation committee engaged Compensia to assist in developing an appropriate group of peer companies, to help us determine the appropriate level of overall compensation for our executive officers, as well as assess each separate element of compensation, with a goal of ensuring that the compensation we offer to our executive officers is competitive and fair.

Our compensation committee periodically considers and assesses Compensia’s independence, including whether Compensia has any potential conflicts of interest with our company or members of our compensation committee. In connection with Compensia’s engagement, our compensation committee conducted such a review and concluded that it was not aware of any conflict of interest that had been raised by work performed by Compensia or the individual consultants employed by Compensia that perform services for our compensation committee.

Pay Components

The Company’s executive compensation program consists of three primary elements: base salaries, annual cash incentives and long-term equity awards.

Our Company is committed to a strong performance orientation in our compensation program and effective corporate governance practices for a company at our development stage and industry.

Base Salary

Base salary provides competitive pay to attract and retain our executives. Annual salary decisions are made in recognition of competitive data as well as the skills and experience that each individual brings to the Company and the performance contributions each makes.

Annual Cash Incentive Program

We maintain an Executive Incentive Compensation Plan (or Incentive Compensation Plan), pursuant to which our named executive officers are eligible to receive cash incentive awards. The Incentive Compensation Plan is designed to provide a financial incentive to reward executives for the achievement of a series of program specific, pipeline, and functional corporate goals. Payments under the plan are ultimately based on achievement of these pre-established corporate goals. Actual performance against targets, as measured by these pre-established corporate goals, funds the incentive payouts. The total bonus payout for participating employees cannot exceed the total amount of funding in the pool. Annual target bonuses are set based on factors such as the executive’s past contributions, tenure, experience, and role and the annual target bonuses provided by companies in our compensation peer group to their similarly situated executives. Bonuses are typically paid in the month following the end of the performance period.

For 2025, the compensation committee maintained the annual bonus target for Mr. Lettmann, as a percentage of his annual salary at 55%. Dr. Pons was not eligible to participate in the Incentive Compensation Plan in 2025 due to his departure from the Company in April 2025. The target annual bonus opportunity for each of our other NEOs, as a percentage of the NEO’s salary, remained at 40%.

Bonuses for all employees, including our NEOs, for the fiscal year ended December 31, 2025, were allocated from a bonus pool funded based on performance against a number of high-impact project and cross-functional goals. The project goals related to specific programs, trials and corporate progress. The cross-functional goals related to business development, positioning for future growth, and development and other functional goals. The combination of the project and cross-functional goals was intended to drive both specific technical achievement and continue to build the foundation for future company growth and advancements.

Each goal is given a specific weighting and measured individually, and the extent of achievement of the goals and the applicable weightings determine the 2025 bonus payout, subject to the compensation committee’s discretion to alter bonus funding and payouts. The 2025 performance goals for Mr. Lettmann were based entirely on corporate goals. The 2025 performance goals for the other NEOs were based 80% on corporate goals and 20% on individual goals.

In January 2026, the compensation committee reviewed the performance against the applicable 2025 corporate and individual goals. Based on the Company’s achievement of the corporate goals, the compensation committee approved funding of the Company’s bonus pool at 75% of target levels related to the corporate goals. Based on the NEOs’ achievement of the individual goals, the compensation committee approved 110% achievement of such individual goals. The resulting bonuses to our NEOs were as follows: Mr. Lettmann ($298,856), Mr. Shantharam ($151,913) and Ms. Wong ($142,874).

Equity Long-Term Incentive Compensation

We believe long-term incentive compensation is an effective means for focusing our executive officers, including the named executive officers, on driving strong performance and increased stockholder value over a multi-year period, provides a meaningful reward for long-term value creation, and motivates them to remain employed with us. This approach more closely aligns the contributions of our executive officers with the long-term interests of our stockholders and allows them to participate in any future appreciation in our common stock.

Severance and Change in Control Protections

In order to recruit and maintain a stable and effective management team, our compensation committee believes it is appropriate and necessary to provide assurance of certain severance and change in control benefits approved by the compensation committee, in consultation with Compensia. We entered into change in control and severance agreements (Severance Agreements) with each of our named executive officers that provide for the severance and change in control benefits. For a summary of the material terms of the benefits provided to our named executive officers under the Severance Agreements and an estimate of the payments and benefits that may be received by our named executive officers under the Severance Agreements, see “Change in Control and Severance Agreements” below.

Other Compensation

Retirement, Welfare, Health and Other Broad-Based Benefits

We maintain a 401(k) retirement savings plan, or 401(k) plan, for the benefit of our employees, including our named executive officers, who satisfy certain eligibility requirements. Our 401(k) plan provides eligible employees with an opportunity to save for retirement on a tax-advantaged basis. Under our 401(k) plan, eligible employees may elect to defer a portion of their compensation, within the limits prescribed by the Internal Revenue Code (Code) and the applicable limits under the 401(k) plan (generally, up to 90% of the employee’s eligible compensation), on a pre-tax or after-tax (Roth) basis, through contributions to the 401(k) plan. All of a participant’s contributions into the 401(k) plan are 100% vested when contributed. The 401(k) plan permits us to make matching contributions and profit-sharing

contributions to eligible participants. The 401(k) plan is intended to qualify under Sections 401(a) and 501(a) of the Code. As a tax-qualified retirement plan, pre-tax contributions to the 401(k) plan and earnings on those pre-tax contributions are not taxable to the employees until distributed from the 401(k) plan, and earnings on Roth contributions are not taxable when distributed from the 401(k) plan. Subject to limits under the Code, in 2025, we provided a 3% employer contribution on gross wages with a maximum annual employer contribution of $10,500 per employee.

Our health and welfare benefits include medical, dental and vision benefits, long-term disability insurance, basic life insurance coverage, health savings and dependent care accounts, and accidental death and dismemberment insurance. Our named executive officers also are eligible to participate in our 2020 Employee Stock Purchase Plan (the ESPP) on the same terms as our other eligible employees. We design our employee benefits programs to be affordable and competitive in relation to the market, and compliant with applicable laws and practices. We adjust our employee benefits programs as needed based upon changes in applicable laws and market practices.

Perquisites and Other Personal Benefits

We do not provide perquisites or other personal benefits to our executive officers, including the named executive officers except in situations where we believe it is appropriate to assist an individual in the performance of his or her duties, to make our executive officers more efficient and effective, and for recruitment and retention purposes.

In the future, we may provide perquisites or other personal benefits in limited circumstances. All future practices with respect to perquisites or other personal benefits for executive officers will be approved and subject to periodic review by the compensation committee.

Employment Agreements

We have entered into employment letters with each of our named executive officers. Each of these agreements was approved by our board of directors or our compensation committee. In filling each of our executive positions, our board of directors and the compensation committee recognized the need to develop competitive compensation packages to attract qualified candidates in a dynamic labor market.

For information on the specific terms and conditions of the employment letters of the named executive officers, see the discussion of “Executive Employment Letter Agreements” below.

Additional Policies and Practices

Hedging and Pledging Prohibitions

As part of our Insider Trading Policy, our contractors, consultants, advisors and employees (including our executive officers and the non-employee members of our board of directors) are prohibited from trading in publicly-traded options, such as puts and calls, and other derivative securities with respect to our securities. This includes any hedging or similar transaction designed to decrease the risks associated with holding shares of our common stock. In addition, our contractors, consultants, advisors and employees (including our executive officers and the non-employee members of our board of directors) are prohibited from holding our common stock in a margin account or pledging our securities as collateral for a loan.

Summary Compensation Table

The following table provides information regarding the compensation of our named executive officers during the years ended December 31, 2025 and 2024.

Outstanding Equity Awards at 2025 Year-End

The following table provides information regarding outstanding equity awards held by our named executive officers as of December 31, 2025.