SNSS Sunesis Pharmaceuticals Inc

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:

Viracta Therapeutics, Inc.

(Name of Registrant as Specified In Its Charter)

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

Payment of Filing Fee (Check the appropriate box):

Dear Stockholders:

We are pleased to invite you to attend the 2023 annual meeting of stockholders (the “Annual Meeting”) of Viracta Therapeutics, Inc., to be held on Thursday, June 8, 2023 at 10:00 a.m., Pacific Time as a virtual meeting. The Annual Meeting will be held in a virtual meeting format only, which we believe affords the same rights and opportunities to participate in the Annual Meeting to all stockholders irrespective of location. You will be able to attend the Annual Meeting virtually by visiting https://www.proxydocs.com/VIRX where you will be able to listen to the meeting live, submit questions and vote online.

The attached formal meeting notice and proxy statement contain details of the business to be conducted at the Annual Meeting.

Your vote is important. Whether or not you attend the Annual Meeting, it is important that your shares be represented and voted at the Annual Meeting. Therefore, we urge you to vote and submit your proxy promptly via the Internet, telephone or mail.

On behalf of our Board of Directors, we would like to express our appreciation for your continued support of and interest in Viracta.

Sincerely,

Mark Rothera

President and Chief Executive Officer

Cardiff, California

VIRACTA THERAPEUTICS, INC.

2533 S. Coast Hwy. 101, Suite 210

Cardiff, California 92007

Explanatory Note

On November 29, 2020, the Company, then operating as Sunesis Pharmaceuticals, Inc., entered into an agreement and plan of merger and reorganization (the “Merger Agreement”) with privately-held Viracta Therapeutics, Inc. (“Private Viracta”) and Sol Merger Sub, Inc., a wholly-owned subsidiary of the Company (“Merger Sub”). On February 24, 2021, Merger Sub merged into Private Viracta, with Private Viracta surviving the merger as a wholly owned subsidiary of the Company (the “Merger”). Sunesis changed its name to Viracta Therapeutics, Inc. On February 25, 2021, the combined company’s common stock began trading on The Nasdaq Global Select Market under the ticker symbol “VIRX”.

Except as otherwise indicated, references herein to “Viracta,” the “Company,” or the “combined company”, refer to Viracta Therapeutics, Inc. on a post-Merger basis, and the term “Private Viracta” refers to the business of privately-held Viracta Therapeutics, Inc., prior to the completion of the Merger. References to “Sunesis” refer to Sunesis Pharmaceuticals, Inc. prior to completion of the Merger.

TABLE OF CONTENTS

VIRACTA THERAPEUTICS, INC.

Who is entitled to vote at the Annual Meeting?

Holders of our common stock as of the close of business on April 19, 2023, the record date for the Annual Meeting, may vote at the Annual Meeting. As of the record date, there were 38,410,935 shares of our common stock outstanding. Each share of common stock is entitled to one vote on each matter properly brought before the Annual Meeting. Stockholders are not permitted to cumulate votes with respect to the election of directors.

Stockholders of Record. If your shares are registered directly in your name with our transfer agent, American Stock Transfer & Trust Company, LLC, then you are considered the stockholder of record with respect to those shares, and the Notice of Internet Availability sent directly to you by us. As a stockholder of record, you have the right to grant your voting proxy directly to the individuals listed on the proxy card or to vote on your own behalf at the Annual Meeting. Throughout this proxy statement, we refer to these holders as “stockholders of record.”

Street Name Stockholders. If your shares are held in a brokerage account or by a broker, bank or other nominee, then you are considered the beneficial owner of shares held in street name, and the Notice of Internet Availability was forwarded to you by your broker, bank or other nominee, which is considered the stockholder of record with respect to those shares. As a beneficial owner, you have the right to direct your broker, bank or other nominee on how to vote the shares held in your account by following the instructions that your broker, bank or other nominee sent to you. Throughout this proxy statement, we refer to these holders as “street name stockholders.”

How many votes are needed for approval of each proposal?

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What is the quorum requirement for the Annual Meeting?

A quorum is the minimum number of shares required to be present or represented at the Annual Meeting for the meeting to be properly held under our amended and restated bylaws and Delaware law. The presence, in person (including virtually) or by proxy, of a majority of the voting power of our capital stock issued and outstanding and entitled to vote will constitute a quorum to transact business at the Annual Meeting. Abstentions, choosing to withhold authority to vote and broker non-votes are counted as present and entitled to vote for purposes of determining a quorum. If there is no quorum, the chairperson of the meeting may adjourn the meeting to another time or place.

How do I vote and what are the voting deadlines?

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

Street Name Stockholders. If you are a street name stockholder, then you will receive voting instructions from your broker, bank or other nominee. The availability of Internet and telephone voting options will depend on the voting process of your broker, bank or other nominee. We therefore recommend that you follow the voting instructions in the materials you receive. If your voting instruction form or notice of internet availability of proxy materials indicates that you may vote your shares through the proxyvote.com website, then you may vote those shares at the Annual Meeting with the control number indicated on that voting instruction form or notice of internet availability of proxy materials. Otherwise, you may not vote your shares at the Annual Meeting unless you obtain a legal proxy from your broker, bank or other nominee.

What if I do not specify how my shares are to be voted or fail to provide timely directions to my broker, bank or other nominee?

Stockholder 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:

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In addition, if any other matters are properly brought before the Annual Meeting, the persons named as proxies will be authorized to vote or otherwise act on those matters in accordance with their judgment.

Street Name Stockholders. Brokers, banks and other nominees holding shares of common stock in street name for customers are generally required to vote such shares in the manner directed by their customers. In the absence of timely directions, your broker, bank or other nominee will have discretion to vote your shares on our sole routine matter: the proposal to ratify the appointment of Ernst & Young LLP as our independent registered public accounting firm for our fiscal year ending December 31, 2023. Your broker, bank or other nominee will not have discretion to vote on any other proposals, which are considered non-routine matters, absent direction from you. In the event that your broker, bank or other nominee votes your shares on our sole routine matter, but is not able to vote your shares on the non-routine matters, then those shares will be treated as broker non-votes with respect to the non-routine proposals. Accordingly, if you own shares through a nominee, such as a broker or bank, please be sure to instruct your nominee how to vote to ensure that your shares are counted on each of the proposals.

Can I change my vote or revoke my proxy?

Stockholder of Record. If you are a stockholder of record, you can change your vote or revoke your proxy before (or at) the Annual Meeting by:

Street Name Stockholders. If you are a street name stockholder, then your broker, bank or other nominee can provide you with instructions on how to change or revoke your proxy.

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

We will be hosting the Annual Meeting via live audio webcast only.

Stockholder of Record. If you were a stockholder of record as of the record date, then you may attend the Annual Meeting virtually, and will be able to submit your questions during the meeting and vote your shares electronically during the meeting by visiting https://www.proxydocs.com/VIRX. To attend and participate in the Annual Meeting, you will need the control number included on your Notice of Internet Availability or proxy card. The Annual Meeting live audio webcast will begin promptly at 10:00 a.m., Pacific Time. We encourage you to access the meeting prior to the start time. Online check-in will begin fifteen minutes prior to the meeting, and you should allow ample time for the check-in procedures.

Street Name Stockholders. If you were a street name stockholder as of the record date and your voting instruction form or notice of internet availability of proxy materials indicates that you may vote your shares through the proxyvote.com website, then you may access and participate in the Annual Meeting with the control number indicated on that voting instruction form or notice of internet availability of proxy materials. Otherwise, street name stockholders should contact their bank, broker or other nominee and obtain a legal proxy in order to be able to attend and participate in the Annual Meeting.

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How can I get help if I have trouble checking in or listening to the Annual Meeting online?

If you encounter difficulties accessing the virtual meeting during the check-in or meeting time, please call the technical support number that will be posted on the virtual meeting log-in page.

What is the effect of giving a proxy?

Proxies are solicited by and on behalf of our board of directors. Mark Rothera, our President and Chief Executive Officer, and Daniel Chevallard, our Chief Operating Officer and Chief Financial Officer, have been designated as proxy holders for the Annual Meeting by our board of directors. When proxies are properly dated, executed and returned, the shares represented by such proxies 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, however, the shares will be voted in accordance with the recommendations of our board of directors on the proposals as described above. If any other matters are properly brought before the Annual Meeting, then the proxy holders will use their own judgment to determine how to vote your shares. If the Annual Meeting is postponed or adjourned, then the proxy holders can vote your shares on the new meeting date, unless you have properly revoked your proxy, as described above.

How can I contact Viracta’s transfer agent?

You may contact our transfer agent, American Stock Transfer & Trust Company, LLC, by telephone at (800) 937-5449, or by writing American Stock Transfer & Trust Company, LLC, at 6201 15^th Avenue, Brooklyn, NY 11219. You may also access instructions with respect to certain stockholder matters (e.g., change of address) via the Internet at https://www.astfinancial.com/.

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 communications or other means by our directors, officers or employees. 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.

Where can I find the voting results of the Annual Meeting?

We will disclose voting results on a Current Report on Form 8-K that we will file with the U.S. Securities and Exchange Commission, or SEC, within four business days after the meeting. If final voting results are not available to us in time to file a Form 8-K, we will file a Form 8-K to publish preliminary results and will provide the final results in an amendment to the Form 8-K as soon as they become available.

Why did I receive a Notice of Internet Availability instead of a full set of proxy materials?

In accordance with the rules of the SEC we have elected to furnish our proxy materials, including this proxy statement and our annual report, primarily via the Internet. As a result, we are mailing to our stockholders a Notice of Internet Availability instead of a paper copy of the proxy materials. The Notice of Internet Availability contains instructions on how to access our proxy materials on the Internet, how to vote on the proposals, how to request printed copies of the proxy materials and our annual report, and how to request to receive all future proxy materials in printed form by mail or electronically by e-mail. We encourage stockholders to take advantage of the availability of the proxy materials on the Internet to help reduce our costs and the environmental impact of our annual meetings.

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What does it mean if I receive more than one Notice of Internet Availability or more than set of printed proxy materials?

If you receive more than one Notice of Internet Availability or more than one set of printed proxy materials, then your shares may be registered in more than one name and/or are registered in different accounts. Please follow the voting instructions on each Notice of Internet Availability or each set of printed proxy materials, as applicable, to ensure that all of your shares are voted.

I share an address with another stockholder, and we received only one paper copy of the Notice of Internet Availability or proxy statement and annual report. How may I obtain an additional copy of the Notice of Internet Availability or proxy statement and annual report?

We have adopted a procedure approved by the SEC called “householding,” under which we can deliver a single copy of the Notice of Internet Availability and, if applicable, the proxy statement and annual report, to multiple stockholders who share the same address unless we receive contrary instructions from one or more 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 deliver promptly a separate copy of the Notice of Internet Availability and, if applicable, the proxy statement and annual report, to any stockholder at a shared address to which we delivered a single copy 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 Notice of Internet Availability or proxy statement and annual report, as applicable, you may contact us as follows:

Viracta Therapeutics, Inc.

Attention: Investor Relations

2533 S. Coast Hwy. 101, Suite 210

Cardiff, California 92007

Tel: (858) 400-8470

Street name stockholders may contact their broker, bank or other nominee to request information about householding.

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?

If a stockholder would like us to consider including a proposal in our proxy statement for our 2024 annual meeting pursuant to Rule 14a-8 of the Exchange Act, then the proposal must be received by our corporate secretary at our principal executive offices on or before December 28, 2023. In addition, stockholder proposals must comply with the requirements of Rule 14a-8 and Rule 14a-19 under the Exchange Act regarding the inclusion of stockholder proposals in company-sponsored proxy materials. Proposals should be addressed to:

Viracta Therapeutics, Inc.

Attention: Corporate Secretary

2533 S. Coast Hwy. 101, Suite 210

Cardiff, California 92007

Our amended and restated bylaws also establish an advance notice procedure for stockholders who wish to present a proposal or nominate a director at an annual meeting, but do not seek to include the proposal or director nominee in our proxy statement. In order to be properly brought before our 2024 annual meeting, the stockholder must provide timely written notice to our corporate secretary, at our principal executive offices, and any such proposal or nomination must constitute a proper matter for stockholder action. The written notice must contain the information specified in our amended and restated bylaws. To be timely, a stockholder’s written notice must be received by our corporate secretary at our principal executive offices no later than December 28, 2023.

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In the event that we hold our 2024 annual meeting more or less than 30 days after the one-year anniversary of this year’s Annual Meeting, then such written notice must be received by our corporate secretary at our principal executive offices:

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

Availability of Bylaws

A copy of our amended and restated bylaws may be obtained by accessing our filings on the SEC’s website at www.sec.gov. You may also contact our corporate secretary at our principal executive offices for a copy of the relevant bylaw provisions regarding the requirements for making stockholder proposals and nominating director candidates.

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BOARD OF DIRECTORS AND CORPORATE GOVERNANCE

Composition of the Board

Our board of directors currently consists of eleven (11) directors, nine (9) of whom are independent under the listing standards of The Nasdaq Stock Market LLC, or Nasdaq. Our board of directors is divided into three classes with staggered three-year terms. Thus, at each annual meeting of stockholders, a class of directors will be elected for a three-year term to succeed the class whose term is then expiring.

Dr. Onetto will not be standing for re-election at the Annual Meeting, and we plan to reduce our board of directors to ten (10) as of the Annual Meeting. Dr. Onetto will continue to serve as a member of the board of directors until the Annual Meeting.

The following table sets forth the names, ages as of April 19, 2023, and certain other information for each of our directors and director nominees:

Nominees for Director

Thomas E. Darcy, CPA, Director

Mr. Darcy has served as a member of the board of directors since February 2021. Mr. Darcy previously was a co-founder and director of Tocagen Inc. from August 2007 until June 2020. Mr. Darcy also served as Tocagen Inc.’s Chief Financial Officer from August 2007 to February 2017 and as Tocagen’s Executive Vice President from August 2007 to May 2017. Prior to Tocagen, Mr. Darcy served for over five years as Executive Vice President and Chief Financial Officer of Science Applications International Corporation (“SAIC”), a Fortune 500 science and technology company. Mr. Darcy also served as a director and chairman of the audit committee of McAfee, Inc., a publicly-held technology company, for over three years until its sale to Intel Corporation in February 2011 and as a director and audit committee member of Forte Biosciences, Inc., a publicly-held biotech company, from June 2020 through May 2021. Mr. Darcy currently also serves as a director and chairman of the

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audit committee of Lytx, Inc., a privately-held technology company. Prior to SAIC, he was an audit Partner in the accounting firm of PricewaterhouseCoopers LLP, where he served as the Managing Partner of both the West and Southwest Region Audit and Business Advisory Service Technology practices, as well as the Managing Partner of the San Diego office. Mr. Darcy is a Certified Public Accountant (inactive) in the state of California and graduated from San Diego State University with a B.S. in Accounting.

We believe Mr. Darcy is qualified to serve on our board of directors because of his life sciences public company experience and his financial and accounting background and expertise.

Jane F. Barlow, M.D., MPH, MBA, Director

Dr. Barlow has served as a member of the board of directors since August 2021. Dr. Barlow is currently the Chief Executive Officer of Jane Barlow & Associates, LLC and a Board Director for ContraFect Corporation and Sera Prognostics. She is Executive Vice President and Chief Clinical Officer at Real Endpoints, a market access consultancy, Senior Advisor to MIT’s Center for Biomedical Innovation and serves on the biotech advisory board of Pictet Asset Management and the advisory board of Refractor Health. Prior to her current roles, she was Associate Chief Medical Officer at CVS Health and Chief Medical Officer of CVS Health Government Services where she successfully implemented industry-leading clinical strategies supporting drug purchasing, distribution, and utilization management. Formerly, she served as Vice President of Clinical Innovation at Medco Health Solutions, leading the adoption of cutting-edge therapeutic programs through all aspects of pharmacy. Dr. Barlow has extensive experience in steering pharmaceutical development and commercialization by strategically weighing the value and economic impact that drug candidates bring to the healthcare ecosystem at large. Dr. Barlow previously served on the boards of Momenta Pharmaceuticals, Inc. (prior to and during its sale to Johnson and Johnson), TherapeuticsMD Inc., and SilverScript Insurance Company. Dr. Barlow received her medical degree from Creighton University School of Medicine and subsequently completed her residency in occupational and environmental medicine at The Johns Hopkins University, where she also earned her MPH. She is a distinguished graduate of the United States Air Force School of Aerospace Medicine and served as Chief of Flight Medicine at the Beale and Maxwell Air Force Bases. Additionally, she holds an MBA from the University of Alabama. She is board-certified in occupational medicine and a fellow of the American College of Occupational and Environmental Medicine and the American College of Preventive Medicine. She is a diplomat of the American College of Physician Executives and a member of the American Medical Association.

We believe that Dr. Barlow is qualified to serve on our board of directors because of her extensive medical and scientific knowledge and experience, as well as her senior management experience in the healthcare industry.

Barry J. Simon, M.D., Director

Dr. Simon has served as a member of the board of directors since March 2021, and previously served on the Private Viracta board of directors from July 2017 until November 2020. Dr. Simon has served as a director since June 2008 and as the Chief Corporate Affairs Officer of ImmunityBio, Inc. (NASDAQ:IBRX), a biopharmaceutical company, since March 2021. Prior to that, Dr. Simon served as Immunity Bio’s President and Chief Administrative Officer from January 2017 to March 2021 and served as President and Chief Operating Officer from March 2015 to December 2016. From 2007 to March 2015, Dr. Simon served as NantKwest Inc.’s President and Chief Executive Officer. Dr. Simon has also served as the Chairman, President and Chief Executive Officer of Brink Biologics, Inc., a bioanalytics, reagents and testings service company, since June 2015. He also previously served on the board of directors of Cue BioPharma, Inc. (NASDAQ:CUE), a biopharmaceutical company from March 2016 to June 2021. Previously, Dr. Simon held Vice President, senior level and advisory positions at F. Hoffmann-La Roche, a global healthcare company, Roche Labs, a pharmaceuticals company, Connetics Corporation (NASDAQ:CNCT), a specialty pharmaceutical company, Immunomedics (NASDAQ:IMMU), a biopharmaceutical company, Immusol, a biopharmaceutical company, HealthPro BioVentures, LLC, a healthcare and life sciences investment bank and NorthSound Capital, LLC, a U.S.-based hedge fund and contributed to several product launches that included Valcyt^® (valganciclovir) for

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CMV retinitis, Xeloda^® (capecitabine) for metastatic breast cancer, Kytril^® (Granisetron) for CINV, Boniva^® (ibandronate) for osteoporosis, Tamiflu^® (oseltamivir) for Influenza, Fortovase^® (saquinavir) and Fuzeon^® (enfuvirtide) for HIV and Pegasys^® (peginterferon alpha-2a) for hepatitis C. Dr. Simon attended corporate training programs by the London School of Business and the Amos Tuck School of Business at Dartmouth College. Dr. Simon trained clinically in Infectious Diseases at Albert Einstein College of Medicine, Anesthesiology at The Mount Sinai Medical Center and Internal Medicine at New York University and received his M.D. from the SUNY Downstate Health Sciences Center in New York.

We believe that Dr. Simon is qualified to serve on our board of directors because of his extensive medical and scientific knowledge and experience, as well as his medical marketing, senior management and commercial experience in the biopharmaceutical industry.

Continuing Directors

Sam Murphy, Ph.D., Director

Dr. Murphy has served as a member of the board of directors since February 2021, and previously served on the Private Viracta board of directors from January 2019 until the closing of the Merger. He has been a Vice President and Head of International Business Development for Shenzhen Salubris Pharmaceutical Co. Ltd. since 2017, and currently serves as Chief Executive Officer of its United States subsidiary, Salubris Biotherapeutics, Inc. Prior to joining Salubris, Dr. Murphy worked for ten years in strategy consulting and transaction advisory services across several global firms including IMS (now IQVIA) and Simon-Kucher & Partners. Dr. Murphy currently serves on the boards of GO Therapeutics, Inc. (chair) and MedAlliance S.A. Dr. Murphy earned a B.A. in Biochemistry, Ph.D. in Molecular Biology with a concentration in Virology and completed his Post-Doctoral Fellowship in Gene Therapy and Translational Medicine at the University of Pennsylvania.

We believe Dr. Murphy is qualified to serve on our board of directors because of his experience as a board member, his scientific background, and his advisory experience in the biotechnology industry.

Roger J. Pomerantz, M.D., Director and Chair

Dr. Pomerantz has served as a member of the board of directors since February 2021, and previously served on the Private Viracta board of directors from 2020 until the closing of the Merger. Dr. Pomerantz has been President, Chief Executive Officer and Chairman of the Board of ContraFect Corporation (NASDAQ: CFRX) since April 2019. Previously, Dr. Pomerantz was a Venture Partner at Flagship Pioneering from 2014 through 2019. In addition, he served as the President, Chief Executive Officer and Chairman of the Board of Seres Therapeutics from 2014-2019, where he continues to serve as Senior Advisor to its Board of Directors. Previously, Dr. Pomerantz was Senior Vice President, Worldwide Head of Licensing & Acquisition at Merck & Co., Inc and prior to that was Senior Vice President and Global Franchise Head of Infectious Diseases at Merck. Prior to joining Merck, Dr. Pomerantz was Global Head of Infectious Diseases for Johnson & Johnson Pharmaceuticals. He also served as Chief Executive Officer of Tibotec Pharmaceuticals, Inc. Dr. Pomerantz currently serves on the boards of Intec Pharma Ltd. (NASDAQ: NTEC), Collplant Biosciences Ltd. (NASDAQ: CLGN) and Indaptus Therapeutics (NASDAQ:INDP). Dr. Pomerantz received his B.A. in Biochemistry at the Johns Hopkins University and his M.D. at the Johns Hopkins School of Medicine. He received post-graduate training at the Massachusetts General Hospital, Harvard Medical School and M.I.T. Dr. Pomerantz is Board Certified in both internal medicine and infectious diseases. He was Professor of Medicine, Biochemistry and Molecular Pharmacology, Chief of Infectious Diseases, and the Founding Director and Chair of the Institute for Human Virology and Biodefense at the Thomas Jefferson University and Medical School.

We believe Dr. Pomerantz is qualified to serve on our board of directors because of his experience as a board member, his scientific background, and his senior management experience in the biotechnology industry.

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Ivor Royston, M.D., Director

Dr. Royston served as Chief Executive Officer, President, and a member of the board of directors from the closing of the Merger in February 2021 until September 2022, from which time Dr. Royston has continued to serve as a Director. Dr. Royston was also Chief Executive Officer and President of Private Viracta from 2015 until the closing of the Merger and a member of Private Viracta (fka Hemaquest)’s board of directors from October 2007 until the closing of the Merger. From 1990 to 2017, Dr. Royston was a Managing Partner of Forward Ventures, a life science venture capital firm. From 1990 to 2000, Dr. Royston also held the position of Chief Executive Officer of the Sidney Kimmel Cancer Center. Prior to that, Dr. Royston was the Director of Clinical Immunology at University of California, San Diego Cancer Center. Dr. Royston was the co-founder of Hybritech, Inc., which developed the PSA test for prostate cancer; and the co-founder of IDEC Corporation, which developed a monoclonal antibody therapy for cancer, and which subsequently merged with Biogen to form Biogen Idec, now Biogen. Dr. Royston currently serves on the board of directors of Biocept, Inc. (NASDAQ:BIOC). Dr. Royston has served as Executive Chairman of Geneditor Biologics Corp. since April 2023. Dr. Royston received his B.A. and M.D. degrees from Johns Hopkins University and completed post-doctoral training in internal medicine and medical oncology at Stanford University.

We believe Dr. Royston is qualified to serve on our board of directors because of the perspective and experience he brings as Viracta’s former President and Chief Executive Officer, his broad experience in the biotechnology industry, his educational background and his medical expertise.

Flavia Borellini, Ph.D., Director

Dr. Borellini has served as a member of the board of directors since August 2021. Dr. Borellini has more than 25 years of executive management experience in the pharmaceutical and biotechnology industry, with a particular focus on global development of targeted oncology drugs, from preclinical to commercial stage. She is the former Chief Executive Officer for Acerta Pharma, where she oversaw the successful development and approval of Calquence^® (acalabrutinib), a selective Bruton’s tyrosine kinase (BTK) inhibitor, for the treatment of mantle cell lymphoma and chronic lymphocytic leukemia (CLL). During her career, Dr. Borellini has also held key senior level positions within AstraZeneca, most recently Global Franchise Head, Hematology, with responsibility for the hematology portfolio in the company’s oncology business unit. While at AstraZeneca, she led the global development, approval, and commercialization of Tagrisso^® (osimertinib), a first-in-class epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor for the treatment of non-small cell lung cancer (NSCLC) caused by the T790M mutation. Prior to her tenure with AstraZeneca, Dr. Borellini spent nearly seven years at Genentech, a member of the Roche Group. During this time, she led the global development, approval and launch of Zelboraf^® (vemurafenib), a first-in-class BRAF inhibitor for the treatment of melanoma caused by the V600E BRAF mutation. Dr. Borellini also served as the program leader for Herceptin^® (trastuzumab), a targeted treatment for HER2 receptor positive cancers, including breast cancer, and Tarceva^® (erlotinib), an EGFR tyrosine kinase inhibitor for the treatment of NSCLC and pancreatic cancer. Dr. Borellini also serves on the Board of Directors of Kartos Therapeutics, Cantargia AP, and Revolution Medicines.

We believe Dr. Borellini is qualified to serve on our board of directors because of her management experience in the pharmaceutical and biotechnology industry.

Stephen Rubino, Ph.D., M.B.A., Director

Dr. Rubino has served as a member of the board of directors since March 2021. Dr. Rubino has over 30 years of pharmaceutical and biotechnology company experience in the areas of business development & licensing, marketing, commercial operations, and strategic planning across a wide range of therapeutic areas. Dr. Rubino is currently President & CEO of Sporos Bioventures, LLC. Dr. Rubino has experience developing and commercializing oncology products both in the US and EU. He has served as the Chief Business Officer of Celyad Oncology, a biotechnology company developing cellular therapies and Chief Business and Strategy

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Officer at Omega Therapeutics. Dr. Rubino held various positions of increasing responsibility at Novartis, a pharmaceutical company, from 2001 until 2017, including most recently as Global Head of Business Development & Licensing and New Product Marketing, Cell & Gene Therapies Unit. Dr. Rubino has served on the boards of directors of Sermonix Pharmaceuticals and Ilkos Therapeutics. Dr. Rubino received a Ph.D. in virology from Cornell University and an M.B.A. from Baruch College.

We believe Dr. Rubino is qualified to serve on our board of directors because of his extensive management and commercial experience in the fields of biotechnology and oncology.

Jane Chung, R.Ph., Director

Ms. Chung has served as a member of the board of directors since August 2022. She has over 20 years of commercial leadership experience in the pharmaceutical and biotechnology industry, focused mostly on innovative oncology medicines and broadly across executive management, franchise leadership, marketing, sales, operations, and market access functions. She is currently the Chief Commercial Officer at Sutro Biopharma, where she has been responsible for building and leading global commercialization since August 2021. Previously, Ms. Chung served in several leadership roles at AstraZeneca Pharmaceuticals, including as President and General Manager of AstraZeneca Canada, Vice President of Sales and Marketing of U.S. lmmuno-Oncology, and Senior Commercial Business Director. Prior to that, Ms. Chung served as a Regional Sales Director and Director of Sales Productivity and Effectiveness for Onyx Pharmaceuticals Inc as well as various commercial roles for Genentech, Inc., including as Commercial Operations Manager, Division Manager and Senior Marketing Manager. Ms. Chung also serves on non-profit boards in the science, education, and community development arenas. Ms. Chung received a B.S. in Pharmacy from St. John’s University and a B.A. in Psychology from Columbia University.

We believe Ms. Chung is qualified to serve on our board of directors because of her extensive commercial leadership experience in biopharma.

Mark Rothera, President & Chief Executive Officer, Director

Mr. Rothera has served as Viracta’s President and Chief Executive Officer and a member of the board of directors since September 2022. Prior to joining Viracta, Mr. Rothera served as President, Chief Executive Officer and a Board Member of Silence Therapeutics, plc, a pharmaceutical company, from September 2020 until February of 2022. From August 2017 to March 2020, Mr. Rothera served as President, CEO and Board Member of Orchard Therapeutics, plc, a biotechnology company. From April 2013 to August 2017, Mr. Rothera served as Chief Commercial Officer of PTC Therapeutics, a biotechnology company. From 2012 to 2013, Mr. Rothera served as Global President of Aegeron Pharmaceuticals, Inc., a biotechnology company. From 2006 to 2012, Mr. Rothera served as Vice President and General Manager for the Europe, Middle East and Africa commercial operations of Shire Human Genetic Therapies, Inc., a pharmaceutical company. Mr. Rothera currently sits on the board of GenPharm, a private life science company. Mr. Rothera received an M.A. in Natural Sciences from Cambridge University, an M.B.A. from the European Institute for Business Administration (INSEAD) and a Diploma in Company Direction from Institute of Directors, United Kingdom.

We believe Mr. Rothera is qualified to serve on our board of directors because of his extensive executive and commercial leadership experience in biopharma and in rare diseases in particular.

Departing Director

Nicole Onetto, M.D., Director

Dr. Onetto has served as a member of the board of directors since September 2019. Dr. Onetto is a medical doctor and independent consultant in oncology, drug development, and translational research. She was Deputy Director

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and Chief Scientific Officer at the Ontario Institute for Cancer Research from 2009 to 2016. From 2005 to 2009 she was Chief Medical Officer at ZymoGenetics, a biotechnology company developing protein therapeutics. From 2002 to 2005, she served at OSI Pharmaceuticals, a biopharma company developing targeted cancer therapies, first as Executive Vice President Oncology, and then as Chief Medical Officer. Her career in the pharmaceutical industry also includes senior management positions at Bristol-Myers Squibb, Nexstar Pharmaceuticals, which was acquired by Gilead Sciences, and Immunex. Dr. Onetto serves as a board member of Basilea Pharmaceutica Ltd. and Bolt Biotherapeutics, Inc. (NASDAQ:BOLT). Previously, Dr. Onetto served for eleven years as a board member of ImmunoGen. Dr. Onetto earned her BS from the University of Paris, and an MS in Pharmacology from the University of Montréal. She obtained her MD and a Hematology-Oncology Certificate from the University of Paris.

Dr. Onetto will be departing from the board of directors following the Annual Meeting and Viracta thanks her for her service as a director.

Director Independence

Our common stock is listed on Nasdaq. As a company listed on Nasdaq, we are required under Nasdaq listing rules to maintain a board comprised of a majority of independent directors as determined affirmatively by our board. Under Nasdaq listing rules, a director will only qualify as an independent director if, in the opinion of that listed company’s board of directors, the director does not have a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. In addition, the Nasdaq listing rules require that, subject to specified exceptions, each member of our audit, compensation and nominating and corporate governance committees be independent.

Audit committee members must also satisfy the additional independence criteria set forth in Rule 10A-3 under the Securities Exchange Act of 1934, as amended, or the Exchange Act, and Nasdaq listing rules applicable to audit committee members. Compensation committee members must also satisfy the additional independence criteria set forth in Rule 10C-1 under the Exchange Act and Nasdaq listing rules applicable to compensation committee members.

Our board of directors has undertaken a review of the independence of each of our directors. Based on information provided by each director concerning his or her background, employment and affiliations, our board of directors has determined that Dr. Barlow, Dr. Borellini, Ms. Chung, Mr. Darcy, Dr. Murphy, Dr. Onetto, Dr. Pomerantz, Dr. Rubino and Dr. Simon, representing nine (9) of our eleven (11) 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 an “independent director” as defined under the listing standards of Nasdaq. Mark Rothera is not considered an independent director because of his position as our chief executive officer and Ivor Royston is not considered an independent director because of his former position as our chief executive officer.

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 that 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 “Related Person Transactions.”

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

Board Leadership Structure

Our corporate governance framework provides our board flexibility to determine the appropriate leadership structure for the company, and whether the roles of chairperson and chief executive officer should be separated or combined. In making this determination, our board considers many factors, including the needs of the business, our board’s assessment of its leadership needs from time to time and the best interests of our stockholders. If the role of chairperson is filled by a director who does not qualify as an independent director, then our corporate governance guidelines provide that one of our independent directors may serve as our lead independent director.

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Our board believes that it is currently appropriate to separate the roles of chairperson and chief executive officer. The chief executive officer is responsible for day-to-day leadership, while our chairperson, along with the rest of our independent directors, ensures that our board’s time and attention is focused on providing independent oversight of management and matters critical to our company. The board believes that Dr. Pomerantz’s deep knowledge of the company and industry, as well as strong leadership and governance experience, enable Dr. Pomerantz to lead our board effectively and independently.

Role of Board in Risk Oversight Process

Risk is inherent with every business, and we face a number of risks, including strategic, financial, business and operational, legal and compliance and reputational. We have designed and implemented processes to manage risk in our operations. Management is responsible for the day-to-day management of risks the company faces, while our board of directors, as a whole and assisted by its committees, has responsibility for the oversight of risk management. Our board reviews strategic and operational risk in the context of discussions, question and answer sessions, and reports from the management team at each regular board meeting, receives reports on all significant committee activities at each regular board meeting, and evaluates the risks inherent in significant transactions.

In addition, our board has tasked designated standing committees with oversight of certain categories of risk management. Our audit committee assists our board in fulfilling its oversight responsibilities with respect to risk management in the areas of internal control over financial reporting and disclosure controls and procedures, legal and regulatory compliance, and also, among other things, discusses with management and the independent auditor guidelines and policies with respect to risk assessment and risk management. Our compensation committee assesses risks relating to our executive compensation plans and arrangements, and whether our compensation policies and programs have the potential to encourage excessive risk taking. Our nominating and corporate governance committee assesses risks relating to our corporate governance practices, the independence of the board and potential conflicts of interest.

Our board of directors believes its current leadership structure supports the risk oversight function of the board.

Board Diversity Matrix

The following table sets forth certain self-identified diversity information for our directors for the current and prior year:

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Board Diversity Matrix (As of October 19, 2022)

Board Committees

Our board of directors has established the following standing committees of the board: audit committee; compensation committee; nominating and corporate governance committee; and science and technology committee. The composition and responsibilities of each of the committees of our board of directors is described below.

Audit Committee

The current members of our audit committee are Mr. Darcy, Dr. Rubino, and Dr. Simon. Mr. Darcy is the chairperson of our audit committee. Our board of directors has determined that each member of our audit committee meets the requirements for independence of audit committee members under the rules and regulations of the SEC and the listing standards of Nasdaq, and also meets the financial literacy requirements of the listing standards of Nasdaq. Our board of directors has determined that Mr. Darcy is an audit committee financial expert within the meaning of Item 407(d) of Regulation S-K. Our audit committee is responsible for, among other things:

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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 of our audit committee is available on our investor relations website at https://viracta.investorroom.com. Our audit committee held four (4) meetings in 2022.

Compensation Committee

The current members of our compensation committee are Dr. Simon, Dr. Barlow, and Mr. Darcy. Dr. Simon is the chairperson of our compensation committee. Former director Michael Huang served on the Compensation Committee until his resignation from the board of directors in August 2022. Our board of directors has determined that each member of our compensation committee meets the requirements for independence for compensation committee members under the rules and regulations of the SEC and the listing standards of Nasdaq. Each member of the compensation committee is also a non-employee director, as defined pursuant to Rule 16b-3 promulgated under the Exchange Act. Our compensation committee is responsible for, among other things:

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 of our compensation committee is available on our investor relations website at https://viracta.investorroom.com. Our compensation committee held four (4) meetings in 2022.

Nominating and Corporate Governance Committee

The current members of our nominating and corporate governance committee are Dr. Rubino, Dr. Barlow, Ms. Chung, Dr. Murphy, and Dr. Onetto. Dr. Rubino is the chairperson of our nominating and corporate governance committee. Former director Michael Huang served on the Compensation Committee until his resignation from the board of directors in August 2022. Our board of directors has determined that each member of our nominating and corporate governance committee meets the requirements for independence for nominating and corporate governance committee members under the listing standards of Nasdaq. Our nominating and corporate governance committee is responsible for, among other things:

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Our nominating and corporate governance committee operates under a written charter. A copy of the charter of our nominating and corporate governance committee is available on our investor relations website at https://viracta.investorroom.com. Our nominating and corporate governance committee held five (5) meetings in 2022.

Science and Technology Committee

We formed a science and technology committee on March 16, 2021. The current members of our science and technology committee are Dr. Onetto, Dr. Borellini, Dr. Murphy, Dr. Royston and Dr. Rubino. Dr. Onetto is the chairperson of our science and technology committee and will continue to serve as such until the Annual Meeting. Our science and technology committee is responsible for, among other things:

Our science and technology committee operates under a written charter. A copy of the charter of our science and technology committee is available on our investor relations website at https://viracta.investorroom.com. Our science and technology committee held three (3) meetings in 2022.

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Attendance at Board and Stockholder Meetings

Our board of directors held six (6) meetings in 2022 (including regularly scheduled and special meetings), and each director attended at least 75% of the aggregate of (1) the total number of meetings of the board of directors held during the period for which he or she has been a director and (2) the total number of meetings held by all committees on which he or she served during the periods that he or she served.

Although we do not have a formal policy regarding attendance by members of our board of directors at the annual meetings of stockholders, we encourage, but do not require, directors to attend. Seven of the ten members of our board of directors at the time of the 2022 Annual Meeting attended our 2022 Annual Meeting.

Executive Sessions of Non-Employee Directors

To encourage and enhance communication among non-employee directors, and as required under applicable Nasdaq rules, our corporate governance guidelines provide that the non-employee directors will meet in executive sessions without management directors or management present on a periodic basis. In addition, if any of our non-employee directors are not independent directors, then our independent directors will also meet in executive session on a periodic basis.

corporate governance committee has discretion to decide which individuals to recommend for nomination as directors and our board of directors has the final authority in determining the selection of director candidates for nomination to our board.

Stockholder Recommendations and Nominations to our Board of Directors

Our nominating and corporate governance committee will consider recommendations and nominations for candidates to our board of directors from stockholders in the same manner as candidates recommended to the committee from other sources, so long as such recommendations and nominations comply with our amended and restated certificate of incorporation and amended and restated bylaws, all applicable company policies and all applicable laws, rules and regulations, including those promulgated by the SEC. Our nominating and corporate governance committee will evaluate such recommendations in accordance with its charter, our bylaws and corporate governance guidelines and the director nominee criteria described above.

A stockholder that wants to recommend a candidate to our board of directors should direct the recommendation in writing by letter to our corporate secretary at Viracta Therapeutics, Inc., 2533 S. Coast Hwy. 101, Suite 210, Cardiff, California 92007, Attention: Corporate Secretary. Such recommendation must include the candidate’s name, home and business contact information, detailed biographical data, relevant qualifications, a signed letter from the candidate confirming willingness to serve, information regarding any relationships between the candidate and us and evidence of the recommending stockholder’s ownership of our capital stock. Such recommendation must also include a statement from the recommending stockholder in support of the candidate. Our nominating and corporate governance committee has discretion to decide which individuals to recommend for nomination as directors.

Under our amended and restated bylaws, stockholders may also directly nominate persons for our board of directors. Any nomination must comply with the requirements set forth in our amended and restated bylaws and the rules and regulations of the SEC, including the requirements of Rule 14a-8 and Rule 14a-19 under the Exchange Act, and should be sent in writing to our corporate secretary at the address above. To be timely for our 2024 annual meeting of stockholders, nominations must be received by our corporate secretary observing the deadlines discussed below under “Other Matters—Stockholder Proposals or Director Nominations for 2024 Annual Meeting.”

Communications with the Board of Directors

Stockholders and other interested parties wishing to communicate directly with our non-management directors, may do so by writing and sending the correspondence to our Chief Financial Officer by mail to our principal executive offices at Viracta Therapeutics, Inc., 2533 S. Coast Hwy. 101, Suite 210, Cardiff, California 92007. Our Chief Financial Officer, in consultation with appropriate directors as necessary, will review all incoming communications and screen for communications that (1) are solicitations for products and services, (2) relate to matters of a personal nature not relevant for our stockholders to act on or for our board to consider and (3) matters that are of a type that are improper or irrelevant to the functioning of our board or our business, for example, mass mailings, job inquiries and business solicitations. If appropriate, our Chief Financial Officer will route such communications to the appropriate director(s) or, if none is specified, then to the chairperson of the board. These policies and procedures do not apply to communications to non-management directors from our officers or directors who are stockholders or stockholder proposals submitted pursuant to Rule 14a-8 under the Exchange Act.

Policy Prohibiting Hedging or Pledging of Securities

Under our insider trading policy, our employees, including our executive officers, and the members of our board of directors are prohibited from, directly or indirectly, among other things, (1) engaging in short sales, (2) trading in publicly-traded options, such as puts and calls, and other derivative securities with respect to our securities

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(other than stock options, restricted stock units and other compensatory awards issued to such individuals by us), (3) purchasing financial instruments (including prepaid variable forward contracts, equity swaps, collars and exchange funds), or otherwise engaging in transactions that hedge or offset, or are designed to hedge or offset, any decrease in the market value of equity securities granted to them by us as part of their compensation or held, directly or indirectly, by them, (4) pledging any of our securities as collateral for any loans and (5) holding our securities in a margin account.

Corporate Governance Guidelines and Code of Business Conduct and Ethics

Our board of directors has adopted corporate governance guidelines. These guidelines address, among other items, the qualifications and responsibilities of our directors and director candidates, the structure and composition of our board of directors 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 code of business conduct and ethics are available on our investor relations website at https://viracta.investorroom.com. We will post amendments to our code of business conduct and ethics or any waivers of our code of business conduct and ethics for directors and executive officers on the same website.

Equity Compensation

Initial Options. Each person who first becomes a non-employee director after the effective date of the non-employee director compensation 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 80,000 shares of our common stock. The Initial Award will be scheduled to vest in equal installments as to 1/36th of the shares of our common stock subject 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 Options. Each continuing non-employee director automatically will receive, on the date of each annual meeting of our stockholders, an annual award (or, the “Annual Award)” of stock options to purchase 40,000 shares of our common stock. Each Annual Award will be scheduled to vest as to 1/12th shares subject to the Annual Award on a monthly basis following the Annual Award’s grant date on the same day of the month as such grant date (or the last day of the month, if there is no corresponding day in such month), or if earlier, 100% of the shares subject to the Annual Award shall vest on the day immediately before the date of the next annual meeting that occurs after the Annual Award’s grant date, subject to continued services to us through the applicable vesting date.

Change in Control. In the event of a change in control, as defined in our 2021 Equity Incentive Plan, each non-employee director’s then outstanding company 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 is granted under our 2021 Equity Incentive Plan (or its successor plan, as applicable) and form of award agreement under such plan. These awards have a maximum term to expiration of 10 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 for Fiscal 2022

The following table sets forth information regarding the total compensation awarded to, earned by or paid to our non-employee directors for their service on our board of directors, for the fiscal year ended December 31, 2022. Directors who are also our employees receive no additional compensation for their service as directors. During 2022, Dr. Royston and Mr. Rothera were employees and executive officers of the company and therefore did not receive compensation as a director while they were employees. Dr. Royston resigned as chief executive officer on September 19, 2022 and was succeeded by Mr. Rothera, and Dr. Royston subsequently received compensation as a non-employee director. The following tables exclude Mr. Rothera and Dr. Royston as each of their

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respective compensation is set forth in the “2022 Summary Compensation Table” below. See “Executive Compensation” for additional information regarding Dr. Royston and Mr. Rothera’s compensation.

The following table lists all outstanding equity awards held by non-employee directors other than our NEOs as of December 31, 2022:

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