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UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No.  )

Filed by the Registrant x

Filed by a Party other than the Registrant o

Check the appropriate box:

QUINCE 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 all boxes that apply):

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Preliminary Proxy-Subject To Completion

611 Gateway Boulevard, Suite 273

South San Francisco, California

94080

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held On Thursday, June 11, 2026

You are cordially invited to attend the 2026 Annual Meeting of Stockholders, or the Annual Meeting, of Quince Therapeutics, Inc., or the Company, on Thursday, June 11, 2026 at 10:00 a.m. Pacific Time. The Annual Meeting will be a completely virtual meeting, conducted via live webcast on the internet at https://web.lumiconnect.com/294872708. There will be no physical location for the Annual Meeting. You will be able to attend and participate in the Annual Meeting online, submit questions during the meeting and vote your shares electronically. In addition, although the live webcast is available only to stockholders at the time of the meeting, following completion of the Annual Meeting, a webcast replay will be posted to the Investor Relations section of our website at https://ir.quincetx.com.

The matters expected to be acted upon at the Annual Meeting are described in the Proxy Statement accompanying this Notice of Annual Meeting of Stockholders. The Annual Meeting materials include this notice, the Notice of Internet Availability of Proxy Materials, the proxy statement, our annual report and the proxy card, each of which is available at https://www.astproxyportal.com/ast/22818/.

Please use this opportunity to take part in our affairs by voting on the business to come before the Annual Meeting. You will receive a Notice of Internet Availability of Proxy Materials, or the Notice, which we expect to mail on or about Thursday, April 30, 2026, unless you have previously requested to receive our proxy materials in paper form. Only stockholders of record at the close of business on Thursday, April 23, 2026 may vote at the Annual Meeting and any postponements or adjournments of the meeting. All stockholders are cordially invited to participate in the Annual Meeting and any postponements or adjournments of the meeting. However, to ensure your representation at the Annual Meeting, please vote as soon as possible by using the internet or telephone, as instructed in the Notice. Alternatively, you may follow the procedures outlined in the Notice to request a paper proxy card to submit your vote by mail. Returning the paper proxy card or voting electronically does NOT deprive you of your right to participate in the virtual meeting and to vote your shares for the matters acted upon at the meeting.

Your vote is important. Whether or not you expect to attend and participate in the Annual Meeting, please submit your proxy electronically via the internet or by telephone by following the instructions in the Notice or if you asked to receive the proxy materials in paper form, please complete, sign and date the proxy card and return it in the postage paid envelope provided.

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IMPORTANT NOTICE REGARDING THE AVAILABILITY OF PROXY MATERIALS FOR THE ANNUAL MEETING TO BE HELD ON JUNE 11, 2026: THE PROXY STATEMENT, PROXY CARD AND ANNUAL REPORT ON FORM 10-K FOR THE FISCAL YEAR ENDED DECEMBER 31, 2025 ARE AVAILABLE FREE OF CHARGE AT HTTP://WWW.ASTPROXYPORTAL.COM/AST/22818.

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Preliminary Proxy-Subject To Completion

QUINCE THERAPEUTICS, INC.

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

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Preliminary Proxy-Subject To Completion

QUINCE THERAPEUTICS, INC.

PROXY STATEMENT FOR THE 2026 ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON THURSDAY, JUNE 11, 2026

APRIL , 2026

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Stockholder of Record: Shares Registered in Your Name

If your shares are registered directly in your name with our transfer agent, Equiniti Trust Company, LLC, you are considered the stockholder of record with respect to those shares, and the Notice or these proxy materials were sent directly to you by Quince.

Beneficial Owner of Shares Held in Street Name: Shares Registered in the Name of a Broker or Nominee

If your shares are held in an account at a brokerage firm, bank, broker-dealer, or other similar organization, then you are the "beneficial owner" of shares held in "street name," and the Notice or these proxy materials were forwarded to you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting. As a beneficial owner, you have the right to instruct that organization on how to vote the shares held in your account. Because you are not the stockholder of record, you may not vote your shares at the Annual Meeting unless you request and obtain a valid proxy from the organization that holds your shares giving you the right to vote the shares at the Annual Meeting. Beneficial owners must obtain a valid proxy from the organization that holds their shares and present it to Equiniti Trust Company, LLC at least two (2) weeks in advance of the Annual Meeting.

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Stockholder of Record: Shares Registered in Your Name

Votes submitted by telephone or through the internet must be received by 11:59 p.m. Eastern Time, on Wednesday, June 10, 2026. Submitting your proxy, whether by telephone, through the internet or by mail if you request or received a paper proxy card, will not affect your right to vote in person should you decide to attend and participate in the meeting virtually.

Beneficial Owner: Shares Registered in the Name of a Broker or Other Nominee

If you are not the stockholder of record, please refer to the voting instructions provided by your nominee to direct it how to vote your shares. Your vote is important. To ensure that your vote is counted, complete and mail the voting instruction card provided by your brokerage firm, bank, or other nominee as directed by your nominee. To electronically vote in person at the meeting online, you must obtain a legal proxy from your nominee. Follow the instructions from your nominee included with our proxy materials or contact your nominee to request a proxy form.

Your vote is important. Whether or not you plan to participate in the Annual Meeting, we urge you to vote by proxy to ensure that your vote is counted.

The telephone and internet voting procedures are designed to authenticate stockholders' identities, to allow stockholders to give their voting instructions and to confirm that stockholders' instructions have been recorded properly.

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If you are present in person or by proxy at the meeting, but abstain from voting on any or all proposals, your shares are still counted as present and entitled to vote. Each proposal listed in this proxy statement identifies the votes needed to approve or ratify the proposed action.

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As a reminder, if you are a beneficial owner of shares held in street name, in order to ensure your shares are voted in the way you would prefer, you must provide voting instructions to your broker, bank or other agent by the deadline provided in the materials you receive from your broker, bank or other agent.

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Accordingly, if you are a beneficial owner of shares held in street name, in order to ensure your shares are voted in the way you would prefer, you must provide voting instructions to your broker or bank by the deadline provided in the materials you receive from your broker or bank.

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Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to revoke a proxy, you must contact that firm to revoke any prior voting instructions.

The meeting webcast will begin promptly at 10:00 am, Pacific Time. We encourage you to access the meeting prior to the start time. Online check-in will begin at 9:30 a.m., Pacific Time, and you should allow ample time for the check-in procedures. We plan to have a webcast replay which will be posted to the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations.

If you choose to receive future proxy materials by email, you will receive an email next year with instructions containing a link to those materials and a link to the proxy voting site. Your election to receive proxy materials by email will remain in effect until you terminate it.

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We have engaged Saratoga Proxy Consulting LLC to assist our board of directors in the solicitation of proxies for the Annual Meeting. We have agreed to pay Saratoga Proxy Consulting LLC a fee of $12,500 and will reimburse Saratoga Proxy Consulting LLC's reasonable and customary out-of-pocket expenses.

Our Bylaws provide that stockholders may present proposals for inclusion in our proxy statement by submitting their proposals in writing to the attention of our Secretary at our principal executive office. Our current principal executive office is located at 611 Gateway Boulevard, Suite 273, South San Francisco, California, 94080. 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"), and related SEC regulations under Rule 14a-8 regarding the inclusion of stockholder proposals in company-sponsored proxy materials. In order to be included in the proxy statement for our 2027 annual meeting of stockholders, stockholder proposals must be received by our Secretary no later than December 31, 2026 and must otherwise comply with the requirements of Rule 14a-8 of the Exchange Act.

Requirements for stockholder proposals to be brought before the annual meeting:

Our Bylaws provide that stockholders may present proposals to be considered at an annual meeting by providing timely notice to our Secretary at our principal executive office. To be timely for our 2027 annual meeting of stockholders, our Secretary must receive the written notice at our principal executive office:

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If we hold our 2027 annual meeting of stockholders more than 30 days before or more than 60 days after June 11, 2027 (the one-year anniversary 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 by our Secretary at our principal executive office:

A stockholder's notice to the Secretary must set forth as to each matter the stockholder proposes to bring before the annual meeting the information required by our Bylaws. If a stockholder who has notified Quince of such stockholder's intention to present a proposal at an annual meeting does not appear to present such stockholder's proposal at such meeting, Quince does not need to present the proposal for vote at such meeting. In addition to satisfying the deadlines in the "advance notice" provisions of our Bylaws, a stockholder who intends to solicit proxies in support of nominees submitted under these "advance notice" provisions, to comply with the universal proxy rules, stockholders who intend to solicit proxies in support of director nominees other than Quince's nominees must include in their notice the information required by Rule 14a-19 under the Exchange Act.

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BOARD OF DIRECTORS AND CORPORATE GOVERNANCE

We have a strong commitment to good corporate governance practices. These practices provide an important framework within which our board of directors, its committees and our management can pursue our strategic objectives in order to promote the interests of our stockholders.

Corporate Governance Guidelines

Our board of directors has adopted Corporate Governance Guidelines that set forth expectations for directors, director independence standards, board committee structure and functions and other policies for the governance of our company. Our Corporate Governance Guidelines are available without charge on the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations, by clicking on "Governance Documents" in the "Governance" section of our website. Our Corporate Governance Guidelines are subject to modification from time to time by our board of directors pursuant to the recommendations of our nominating and corporate governance committee.

Classified Board

At this time, our board of directors believes that the classified board structure is in the best interests of the Company and its stockholders. The classified board structure and corresponding three-year terms are intended to ensure that our directors have sufficient institutional knowledge of our business, corporate strategy and corporate objectives while also allowing for corporate continuity and stability of the board of directors, promoting the balance of long-term and short-term interests of the Company and its stockholders. Our board of directors believes a three-year term in office also allows our directors to stay focused on long-term value creation. Further, our board of directors believes that a classified board structure enables us to attract and retain diverse and highly qualified individuals willing to commit the time and dedication necessary to understand our business, its operations and its competitive environment. For example, a substantial amount of diversity on our Board is represented by directors who have joined our board of directors in the last three years. The structure also safeguards us from third-party takeover attempts, as it will require a longer period to change the majority control of the board of directors.

Board Leadership Structure

Our Corporate Governance Guidelines provide that our board of directors shall be free to choose its Chairperson in any way that it considers in the best interests of our company, and that our nominating and corporate governance committee periodically considers the leadership structure of our board of directors and makes such recommendations to our board of directors with respect thereto as appropriate. In addition, our Corporate Governance Guidelines provide that, when the positions of Chairperson and Chief Executive Officer are held by the same person, our board of directors will designate a Lead Independent Director. Because the Chair of our board of directors is not our Chief Executive Officer, we do not currently have a separate lead independent director. The independent members of the board of directors also meet in executive session without management, which provides the board of directors with the benefit of having the perspective of independent directors. The Chairperson presides over these executive sessions.

David A. Lamond serves as the Chairperson of our board of directors. We believe the leadership structure reinforces the independence of our board of directors in its oversight of the business and affairs of our Company. In addition, we believe that having separate CEO and independent Chairperson positions creates an environment that is more conducive to objective evaluation and oversight of management's performance, increasing management accountability and improving the ability of our board of director to monitor whether management's actions are in the best interests of our Company and its stockholders. Our board of directors believes that our Company and stockholders are best served by maintaining flexibility to determine whether and when the Chairperson and CEO positions should be separate or combined to provide the best leadership for our Company.

Lead Independent Director

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The responsibilities of the Lead Independent Director, if appointed, include:

Our Board of Directors' Role in Risk Oversight

One of the key functions of our board of directors is informed oversight of our risk management process. Although our board of directors does not have a standing risk management committee, it administers this oversight function directly through the board of directors as a whole, as well as through its standing committees that address risks inherent in their respective areas of oversight. Areas of focus include economic, operational, financial (accounting, credit, investment, liquidity and tax), competitive, legal, regulatory, cybersecurity, privacy, and compliance and reputational risks. The risk oversight responsibility of our board of directors and its committees is supported by our management reporting processes, which are designed to provide visibility to our board of directors and to our personnel who are responsible for risk assessment and information about the identification, assessment and management of critical risks, and our management's risk mitigation strategies.

Our audit committee is responsible for reviewing and discussing our major financial risk exposures and the steps our management has taken to monitor and control these exposures, including guidelines and policies with respect to risk assessment and risk management. The audit committee also monitors compliance with legal and regulatory requirements and assists our board of directors in fulfilling its oversight responsibilities with respect to risk management. Our nominating and corporate governance committee assesses risks related to our corporate governance practices, the independence of our board of directors and monitors the effectiveness of our governance guidelines. Our compensation committee assesses and monitors whether our compensation policies and programs have the potential to encourage excessive risk-taking.

We believe this division of responsibilities is an effective approach for addressing the risks we currently face and that our board leadership structure supports this approach.

Independence of Directors

The Nasdaq listing rules generally require that a majority of the members of a listed company's board of directors be independent. In addition, the listing rules generally require that, subject to specified exceptions, each member of a listed company's audit, compensation and nominating and corporate governance committees be independent.

In addition, audit committee members must also satisfy the independence criteria set forth in Rule 10A-3 under the Securities Exchange Act of 1934, as amended, or the Exchange Act. In order to be considered independent for purposes of Rule 10A-3, a member of an audit committee of a listed company may not, other than in such member's capacity as a

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member of the audit committee, the board of directors or any other board committee (i) accept, directly or indirectly, any consulting, advisory or other compensatory fee from the listed company or any of its subsidiaries or (ii) be an affiliated person of the listed company or any of its subsidiaries.

Our board of directors conducts an annual review of the independence of our directors. Our board of directors has determined that none of the non-management members of our board of directors has a relationship that would interfere with the exercise of independent judgment in carrying out the responsibilities of a director. Each of the members of our board of directors, other than Dr. Thye, our Chief Executive Officer and Chief Medical Officer, is "independent" as that term is defined under the rules of Nasdaq. Our board of directors has also determined that all members of our audit committee, compensation committee and nominating and corporate governance committee are independent and satisfy the relevant SEC and Nasdaq independence requirements for such committees.

Committees of Our Board of Directors

Our board of directors has established an audit committee, a compensation committee and a nominating and corporate governance committee. The composition and responsibilities of each committee are described below. Each of these committees has a written charter approved by our board of directors. Copies of the charters for each committee are available on the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations, by clicking on "Governance Documents" in the "Governance" section of our website. Members serve on these committees until (i) they resign from their respective committee, (ii) they no longer serve as a director or (iii) as otherwise determined by our board of directors.

Audit Committee

Our audit committee is currently composed of Christopher J. Senner, who is the chair of our audit committee, and David Lamond. The composition of our audit committee meets the requirements for independence under current Nasdaq listing standards and SEC rules and regulations. Each member of our audit committee is financially literate. In addition, our board of directors has determined that Mr. Senner is an audit committee financial expert within the meaning of Item 407(d) of Regulation S-K of the Exchange Act. This designation does not impose any duties, obligations or liabilities that are greater than those generally imposed on members of our audit committee and our board of directors. Our audit committee is current composed of only two directors. We anticipate appointing an additional independent director to our audit committee prior to July 29, 2026, to comply with Nasdaq requirements.

Our audit committee, among other things:

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Our audit committee has a written charter approved by our board of directors. A copy of the charter is available on the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations, by clicking on "Governance Documents" in the "Governance" section of our website.

Compensation Committee

Our compensation committee is currently composed of David A. Lamond, who is the chair of our compensation committee, and Christopher J. Senner. The composition of our compensation committee meets the requirements for independence under current Nasdaq listing standards and SEC rules and regulations. Each member of this committee is also a non-employee director, as defined pursuant to Rule 16b-3 promulgated under the Exchange Act. Our compensation committee, among other things:

The compensation committee may delegate its authority to a subcommittee of the compensation committee (consisting either of a subset of members of the committee or, after giving due consideration to whether the eligibility criteria described within the compensation committee charter with respect to committee members and whether such other board members satisfy such criteria, any members of the board of directors) except for its exclusive authority to determine the amount and form of compensation paid to the Chief Executive Officer.

Our compensation committee has a written charter approved by our board of directors. A copy of the charter is available on the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations, by clicking on "Governance Documents" in the "Governance" section of our website.

Compensation Committee Processes and Procedures

Typically, the compensation committee meets at least four times annually and with greater frequency if necessary. The agenda for each meeting is developed by the chair of the compensation committee. The compensation committee meets regularly in executive session. In addition, members of management and other employees as well as outside advisors or consultants are regularly invited by the compensation committee to make presentations, to provide financial or other background information or advice or to otherwise participate in compensation committee meetings. However, the compensation committee meets regularly without such members present, and in all cases members of management are not

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present during the portion of meetings at which their compensation or performance is discussed or determined. Under the charter of the compensation committee, the compensation committee has the authority to obtain, at our expense, advice and assistance from compensation consultants and internal and external legal, accounting or other advisors and other external resources that the compensation committee considers necessary or appropriate in the performance of its duties, including compensation consultants to assist in its evaluation of executive and director compensation. Under the charter, before selecting a compensation consultant, legal counsel or other adviser, the compensation committee must consider all factors related to the independence of such advisors, including those specified by the Nasdaq listing rules.

The compensation committee retained Compensia, Inc., or Compensia, as its independent compensation consultant. The compensation committee requested that Compensia assist in evaluating the efficacy of our existing compensation strategy and practices in supporting and reinforcing our long-term strategic goals and in refining our compensation strategy and in developing and implementing an executive compensation program to execute that strategy and to ensure that our compensation programs remain competitive in attracting and retaining talented executives. At the request of the compensation committee, Compensia also conducted individual interviews with members of the compensation committee and senior management to learn more about our business operations and strategy, key performance metrics and strategic goals, as well as the labor markets in which we compete.

In addition, as part of its engagement, our compensation committee requested that Compensia develop a group of peer companies to use as a reference in making compensation decisions, evaluating current pay practices and considering different compensation programs and best practices. Following an active dialogue with Compensia, the compensation committee recommended that the board of directors approve the recommendations of Compensia.

Nominating and Corporate Governance Committee

Our nominating and corporate governance committee is currently composed of David A. Lamond, who is the chair of our nominating and corporate governance committee, and Christopher J. Senner. The composition of our nominating and corporate governance committee meets the requirements for independence under current Nasdaq listing standards and SEC rules and regulations. Our nominating and corporate governance committee, among other things:

Our nominating and corporate governance committee has a written charter approved by our board of directors. A copy of the charter is available on the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations, by clicking on "Governance Documents" in the "Governance" section of our website.

Board and Committee Meetings and Attendance

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Our board of directors and its committees meet regularly throughout the year, and also hold special meetings and act by written consent from time to time. During 2025: (i) our board of directors met four (4) times; (ii) our audit committee met four (4) times; (iii) our compensation committee met two (2) times; and (iv) our nominating and corporate governance committee met two (2) times.

During 2025, each member of our board of directors attended at least 75% of the aggregate of all meetings of our board of directors and of all meetings of committees of our board of directors on which such member served that were held during the period in which such director served.

Board Composition

Due to the global and complex nature of our business, the Board believes it is important to consider education, age, cultural background, and professional experiences in evaluating board candidates in order to provide practical insights and diverse perspectives. Our Board monitors the mix of skills and experience of its directors to help ensure it has the necessary tools to perform its oversight function effectively. The Board fully appreciates the value of a diversity of viewpoints, background and experiences as important to the selection of directors to enhance the Board's cognitive diversity and quality of dialogue in the Boardroom. Our nominating and corporate governance committee is committed to actively seeking out and will instruct any search firm it engages to identify, individuals who will contribute to the overall diversity of the board of directors to be included in the pool of candidates from which nominees to the board of directors are selected.

Board Attendance at Annual Meeting of Stockholders

Our policy is to invite and encourage each member of our board of directors to be present at our annual meetings of stockholders. The 2025 Annual meeting was attended by five of eight then-serving directors.

Communication with Directors

Stockholders and interested parties who wish to communicate with our board of directors, non-management members of our board of directors as a group, a committee of our board of directors or a specific member of our board of directors (including our Chairperson) may do so by letters addressed to our Secretary.

All communications are reviewed by the Secretary and provided to the members of our board of directors as appropriate. Unsolicited items, sales materials, abusive, threatening or otherwise inappropriate materials and other routine items and items unrelated to the duties and responsibilities of our board of directors will not be provided to directors.

The address for these communications is:

Quince Therapeutics, Inc.

611 Gateway Boulevard, Suite 273

South San Francisco, California 94080

Attn: Secretary

Code of Business Conduct and Ethics

We have adopted a Code of Business Conduct and Ethics that applies to all of the members of our board of directors, officers and employees. Our Code of Business Conduct and Ethics is posted on the Investor Relations section of our website, which is located at https://ir.quincetx.com/investor-relations, by clicking on "Governance Documents" in the "Governance" section of our website. We intend to satisfy the disclosure requirement under Item 5.05 of Form 8-K regarding amendment to, or waiver from, a provision of our Code of Business Conduct and Ethics by posting such information on our website at the location specified above.

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Insider Trading Policy

We have adopted an insider trading policy governing the purchase, sale, and/or other dispositions of the Company's securities by directors, officers and employees that is designed to promote compliance with insider trading laws, rules and regulations, as well as procedures designed to further the foregoing purposes. A copy of our insider trading policy is filed as an exhibit to our Annual Report on Form 10-K for our fiscal year ended December 31, 2025. In addition, it is the Company's intent to comply with applicable laws and regulations relating to insider trading

Hedging and Pledging Policy

Under the terms of our insider trading policy, our directors, officers, employees, and consultants are prohibited from engaging in hedging or monetization transactions involving our securities, such as prepaid variable forward contracts, equity swaps, collars or exchange funds. In addition, our insider trading policy prohibits such persons from trading in publicly-traded options, such as puts and calls, and other derivative securities with respect to our securities (other than stock options and other compensatory equity awards issued by us), as well as pledging our securities as collateral for a loan.

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REPORT OF THE AUDIT COMMITTEE

The material in this report is not "soliciting material," is not deemed "filed" with the Commission and is not to be incorporated by reference in any filing of the Company under the Securities Act or the Exchange Act, whether made before or after the date hereof and irrespective of any general incorporation language in any such filing

Our audit committee has reviewed and discussed with our management and BDO USA, P.C., our audited financial statements for the fiscal year ended December 31, 2025. Our audit committee has also discussed with BDO USA, P.C. the matters required to be discussed by the applicable requirements of the Public Company Accounting Oversight Board and the SEC.

Our audit committee has received and reviewed the written disclosures and the letter from BDO USA, P.C. required by applicable requirements of the PCAOB regarding the independent accountant's communications with our audit committee concerning independence, and has discussed with BDO USA, P.C. its independence from us.

Based on the review and discussions referred to above, our audit committee recommended to our board of directors that the audited financial statements be included in our annual report on Form 10-K for the fiscal year ended December 31, 2025 for filing with the SEC.

Submitted by the Audit Committee

Christopher J. Senner, Chair

David Lamond

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NOMINATIONS PROCESS AND DIRECTOR QUALIFICATIONS

Nomination to the Board of Directors

Candidates for nomination to our board of directors are selected by our board of directors based on the recommendation of our nominating and corporate governance committee in accordance with its charter, our amended and restated certificate of incorporation and amended and restated bylaws, our Corporate Governance Guidelines and the criteria approved by our board of directors regarding director candidate qualifications. In recommending candidates for nomination, our nominating and corporate governance committee considers candidates recommended by directors, officers, employees, and stockholders. The Committee has engaged and may engage in the future consultants or third-party search firms to assist in identifying and evaluating potential nominees using the same criteria to evaluate all candidates.

Additional information regarding the process for properly submitting stockholder nominations for candidates for nomination to our board of directors is set forth under "When are stockholder proposals due for next year's annual meeting?"

Director Qualifications

With the goal of developing a diverse, experienced and highly qualified board of directors, our nominating and corporate governance committee is responsible for developing and recommending to our board of directors the desired qualifications, expertise and characteristics of members of our board of directors, including any specific minimum qualifications that the committee believes must be met by a committee-recommended nominee for membership on our board of directors and any specific qualities or skills that the committee believes are necessary for one or more of the members of our board of directors to possess.

Because the identification, evaluation and selection of qualified directors is a complex and subjective process that requires consideration of many intangible factors, and will be significantly influenced by the particular needs of our board of directors from time to time, our board of directors has not adopted a specific set of minimum qualifications, qualities or skills that are necessary for a nominee to possess, other than those that are necessary to meet U.S. legal, regulatory and Nasdaq listing requirements and the provisions of our amended and restated certificate of incorporation and amended and restated bylaws, our Corporate Governance Guidelines and the charters of the committees of our board of directors. When considering nominees, our nominating and corporate governance committee may take into consideration many factors including, among other things, a candidate's independence, integrity, diversity, skills, financial and other expertise, breadth of experience, knowledge about our business or industry and ability to devote adequate time and effort to responsibilities of our board of directors in the context of its existing composition. Our board of directors does not have a formal policy with respect to diversity and inclusion; however, it affirms the value placed on diversity within our company. Through the nomination process, our nominating and corporate governance committee seeks to promote board membership that reflects a diversity of business experience, expertise, viewpoints, personal backgrounds and other characteristics that are expected to contribute to our board of directors' overall effectiveness. Further, our board of directors is committed to actively seeking highly qualified women and individuals from minority groups to include in the pool from which new candidates are selected. The brief biographical description of each director set forth below includes the primary individual experience, qualifications, attributes and skills of each of our directors that led to the conclusion that each director should serve as a member of our board of directors at this time.

Continuing Directors

The directors who are serving for terms that end following the Annual Meeting and their ages, occupations and lengths of service on our board of directors as of April 16, 2025 are provided in the table below and in the additional biographical descriptions set forth in the text below the table.

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Directors Continuing in Office Until the 2027 Annual Meeting

Dirk Thye, M.D. has served as our Chief Executive Officer and member of the Board of Directors since May 2022 and Chief Medical Officer since January 2024. Prior to joining Quince Therapeutics, Inc., he served as the Chief Executive Officer of Novosteo Inc. from September 2021 to May 2022. Previously, Dr. Thye was the Executive Chairman of Geom Therapeutics, Inc. from January 2016 to July 2020 and the Chief Executive Officer of Agenovir Corporation from September 2016 to January 2018. Dr. Thye holds a M.D. from the University of California, Los Angeles and a B.A. in Molecular Biology from the University of California, Berkeley. We believe that Dr. Thye's extensive experience in the biotechnology industry as an executive officer, as well as his education in biotechnology qualifies him to serve as a director.

David A. Lamond has served on our board of directors since December 2015. Mr. Lamond has served as the president of En Pointe LLC, an investment firm, since 2016. He served as the President, Chief Executive Officer and Chief Investment Officer of Lamond Capital Partners LLC from 2011 to 2016. He also serves on the board of directors of EG 427, a biotechnology company, Inquis Medical, a medical device company and Windfall Data, an analytics company. He previously served on the board of Applied Molecular Transport, a biotechnology company, and Arrinex, a medical device company until its acquisition by Stryker Corporation in February 2019. Mr. Lamond holds a B.A. in History from Duke University and a J.D. from Duke Law School. We believe that Mr. Lamond is qualified to serve as a director because his extensive experience with important ecosystem partners and his service on a number of boards provides an important perspective on operations, finance and corporate governance matters.

Directors Continuing in Office Until the 2028 Annual Meeting

Christopher J. Senner has served on our board of directors since March 2019. Mr. Senner has served as Executive Vice President and Chief Financial Officer for Exelixis, Inc. since 2015. Prior to joining Exelixis, Inc., Mr. Senner served as Vice President, Corporate Finance for Gilead Sciences, Inc., a biopharmaceutical company, from 2010 to 2015, where he was accountable for controllership, tax, treasury and corporate and operational financial planning. Mr. Senner previously spent 18 years at Wyeth, a pharmaceutical company acquired by Pfizer Inc. in 2009, in a variety of financial roles with increasing responsibility, most notably as Chief Financial Officer of Wyeth's United States pharmaceuticals business and the BioPharma business unit. Mr. Senner holds an undergraduate degree in Finance from Bentley College. We believe that Mr. Senner's extensive executive and professional experience in the biotechnology industry qualifies him to serve as a director.

There are no family relationships among our directors and executive officers.

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PROPOSAL ONE: APPROVAL OF AMENDMENT TO OUR CERTIFICATE OF INCORPORATION TO EFFECT A REVERSE STOCK SPLIT

Our Board has approved, and is recommending that our stockholders approve, a proposed amendment to our certificate of incorporation, to effect a reverse split of the issued and outstanding shares of the common stock at a ratio ranging from one-for-ten to one-for-one-hundred, or the Reverse Stock Split. The form of proposed amendment to our certificate of incorporation to effect the Reverse Stock Split is attached as Appendix A to this proxy statement, or the Certificate of Amendment. The text of the proposed amendment is subject to revision to include such changes as may be required by the Secretary of State of the State of Delaware and as our board of directors deems necessary or advisable to effect the proposed amendment of the certificate of incorporation. If a certificate of amendment is filed with the Secretary of State of the State of Delaware, the certificate of amendment to the certificate of incorporation will affect the Reverse Stock Split by reducing the outstanding number of shares of the common stock by the ratio to be determined by the board of directors, but will not increase the par value of the common stock and will not change the number of authorized shares of the common stock. If the board of directors does not implement an approved Reverse Stock Split prior to the one-year anniversary of this meeting, the board of directors will seek stockholder approval before implementing any Reverse Stock Split after that time.

If this proposal is approved by our stockholders, our board of directors will have the sole discretion to effect the Reverse Stock Split at any time prior to the one-year anniversary of the Annual Meeting and to fix the specific ratio for the Reverse Stock Split at a ratio not less than one-for-ten and not greater than one-for-one-hundred. In addition, if this proposal is approved and our board of directors determines to proceed with the Reverse Stock Split, we will file a Certificate of Amendment to effect the Reverse Stock Split. If approved, our board of directors may also elect not to effect any Reverse Stock Split and consequently not file any Certificate of Amendment.

The Reverse Stock Split will take effect, if at all, only after it is (i) approved by the affirmative vote of a majority of the votes cast for or against this proposal and entitled to vote on the matter, (ii) is deemed by the board of directors to be in the best interests of the Company and its stockholders, and (iii) after filing the Certificate of Amendment with the Secretary of State of the State of Delaware. If the Certificate of Amendment is filed with the Secretary of State of the State of Delaware, the Certificate of Amendment will effect the Reverse Stock Split by reducing the outstanding number of shares of the Common Stock by the ratio to be determined by the board of directors, but will not change the par value of our common stock, and will not change the number of authorized shares of the Common Stock. If the board of directors does not implement an approved Reverse Stock Split prior to the one-year anniversary of this meeting, the board of directors will seek stockholder approval before implementing any Reverse Stock Split after that time. You should keep in mind that the implementation of a reverse stock split does not have an effect on your proportional ownership of our business.

Reasons for the Reverse Stock Split

Our common stock is listed on the Nasdaq Global Select Market under the symbol "QNCX." As previously disclosed, on March 16, 2026, Nasdaq notified us that the bid price of our common stock had closed below the required $1.00 per share for 30 consecutive trading days, and, accordingly, that we did not comply with the applicable minimum $1.00 per share required for continued listing under Listing Rule 5450(a)(1), or the Minimum Bid Price Requirement, for continued listing on the Nasdaq Stock Market. In order to regain compliance, the minimum bid price of our common stock must close at or above $1.00 for a period of at least ten trading days. On April 10, 2026, we effected a one-for-ten reverse stock split, which was effective on the Nasdaq Global Select Market beginning on April 13, 2026, as approved by our stockholders at our 2025 annual meeting of stockholders. While our common stock has closed above $1.00 since effecting such reverse stock split, our board of directors believes it is necessary to seek stockholder approval of this proposal to ensure that we will be able to regain and maintain compliance with the Minimum Bid Price Requirement. Even if we regain compliance with the Minimum Bid Price Requirement without effecting the Reverse Stock Split, our board of directors may determine that it is in the best interests of Quince and our stockholders to effect the Reverse Stock Split in the future to enable us to maintain compliance with the Minimum Bid Price Requirement and to address concerns relating to low-priced stocks, described in greater detail below.

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If our common stock were delisted from the Nasdaq Stock Market, the board of directors believes that such delisting would adversely affect the market liquidity of our common stock, decrease the market price of our common stock, adversely affect our ability to obtain financing for the continuation of our operations and result in the loss of confidence in our company. In the event that our stockholders fail to approve this proposal, we could be prevented regaining compliance with the Minimum Bid Price Requirement and maintaining such compliance in the future. In addition, as previously disclosed, our board of directors is considering strategic options available to the Company, including, but not limited to, a reverse merger. If our board of directors determines that it is in the best interests of the Company and our stockholders to pursue a reverse merger, the Reverse Stock Split may be necessary to effecting such a transaction.

Our board of directors has considered the potential harm to us of a delisting of the common stock and has determined that, if we are not otherwise able to regain and maintain compliance with the Minimum Bid Price Requirement, the consummation of the Reverse Stock Split is the best way to regain and maintain compliance with the Minimum Bid Price Requirement. Our board of directors also believes that the current low per share market price of the common stock has a negative effect on the marketability of our existing shares. Our board of directors believes there are several reasons for this effect. First, certain institutional investors have internal policies preventing the purchase of low-priced stocks. Second, a variety of policies and practices of broker-dealers discourage individual brokers within those firms from dealing in low-priced stocks. Third, because the brokers' commissions on low-priced stocks generally represent a higher percentage of the stock price than commissions on higher priced stocks, the current share price of the common stock can result in individual stockholders paying transaction costs (commissions, markups or markdowns) that are a higher percentage of their total share value than would be the case if the share price of the common stock were substantially higher. This factor is also believed to limit the willingness of some institutions to purchase the common stock. Our board of directors anticipates that a Reverse Stock Split will result in a higher bid price for our common stock, which may help to alleviate some of these problems.

The market price of our common stock is dependent upon our performance and other factors, some of which are unrelated to the number of shares of common stock issued and outstanding. If the Reverse Stock Split is effected and the market price of our common stock declines, the percentage decline as an absolute number and as a percentage of our overall market capitalization may be greater than would occur in the absence of the Reverse Stock Split. Furthermore, the reduced number of shares of common stock that will be issued and outstanding after the implementation of the Reverse Stock Split could significantly reduce the trading volume and otherwise adversely affect the liquidity of our common stock.

We have not proposed the Reverse Stock Split Proposal in response to any effort of which we are aware to accumulate our shares of Common Stock or obtain control of the Company, nor is it a plan by management to recommend a series of similar actions to our Board or our stockholders. Notwithstanding the decrease in the number of issued and outstanding shares of Common Stock following a reverse stock split, our Board does not intend for this transaction to be the first step in a "going private transaction" within the meaning of Rule 13e-3 of the Exchange Act.

If this Proposal One is approved by the affirmative vote of a majority of the votes cast for or against this proposal and entitled to vote on the matter and our board of directors decides to implement the Reverse Stock Split, our board of directors will determine whether to effect a Reverse Stock Split at a ratio ranging from one-for-ten to one-for-one-hundred.

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

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Even if the minimum bid price of our common stock following the Reverse Stock Split, if approved, remains in excess of $1.00 per share, we may be delisted due to our failure to meet other continued listing requirements, including the minimum market value of listed securities requirement. As previously disclosed, on March 17, 2026, we received a notice from Nasdaq that the market value of our listed securities ("MVLS") for the last 30 consecutive business days was less than the $50,000,000 required for continued listing on the Nasdaq Global Select Market under Listing Rule 5450(b)(2)(A) (the "MVLS Requirement"). We have a period of 180 calendar days, or until September 14, 2026, to regain compliance with the MVLS Requirement. The Reverse Stock Split, in and of itself, will not resolve our compliance with the MVLS Requirement and we may need to take further action in the future to regain compliance with the MVLS Requirement, including, but not limited to, transferring our listing from the Nasdaq Global Select Market to the Nasdaq Capital Market.

Criteria to be Used for Determining Whether to Implement Reverse Stock Split

In determining whether to implement the Reverse Stock Split following receipt of stockholder approval of this Proposal 1, our board of directors may consider, among other things, various factors, such as:

The failure of our stockholders to approve this Proposal 1 could have serious, adverse effects on us and our stockholders. We could be delisted from the Nasdaq Stock Market because shares of common stock may continue to trade below the requisite $1.00 per share bid price needed to maintain our listing. If our common stock is delisted from the Nasdaq Stock Market, our shares may then trade on the OTC Bulletin Board or other small trading markets, such as the pink sheets. In that event, the common stock could trade thinly as a microcap or penny stock, adversely decrease to nominal levels of trading and be avoided by retail and institutional investors, resulting in the impaired liquidity of our shares.

Our board of directors reserves the right to abandon the Reverse Stock Split without further action by our stockholders at any time before the effectiveness of our Certificate of Amendment, even if the Reverse Stock Split has been authorized by our stockholders. By voting in favor of the Reverse Stock Split, you are expressly authorizing our board of directors to determine not to proceed with, and abandon, the Reverse Stock Split if our board of directors should so decide.

Effects of the Reverse Stock Split

The following table is provided for illustrative purposes only to set forth approximate information regarding (i) the number of shares of common stock that would be authorized for issuance, (ii) the number of shares of our common stock that would be issued and outstanding, (iii) the number of shares of our Common Stock that would be reserved for issuance pursuant to outstanding equity awards, (iii) the number of shares of Common Stock reserved for issuance upon exercise of outstanding warrants, and (iv) the per share price of our Common Stock, based on the closing price of our Common Stock on April 23, 2026 ($ per share), each giving effect to the Reverse Split at various ratios within the proposed range,

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without taking into account the treatment of fractional shares and based on securities outstanding as of April 23, 2026. The effects of the Reverse Stock Split are described in further detail following the table.

Effects of a Reverse Stock Split on Issued and Outstanding Shares

If the Reverse Stock Split is effected, it will reduce the total number of issued and outstanding shares of common stock by a ratio of 1-for-10 to 1-for-100, with the actual ratio determined in the sole discretion of our board of directors. Accordingly, each of our stockholders will own fewer shares of common stock as a result of the Reverse Stock Split. However, the Reverse Stock Split will affect all stockholders uniformly and will not affect any stockholder's percentage ownership interest in the Company, except to the extent that the Reverse Stock Split would result in an adjustment to a stockholder's ownership of common stock due to the treatment of fractional shares in the Reverse Stock Split. After the Reverse Stock Split, each share of the common stock will have the same voting rights and rights to dividends and distributions and will be identical in all other respects to the common stock now authorized and common stock issued pursuant to the Reverse Stock Split will remain fully paid and non-assessable.

We are currently authorized to issue a maximum of 250,000,000 shares of our common stock. The number of authorized shares of our common stock will not change as a result of the Reverse Stock Split; however, the number of shares of our common stock issued and outstanding will be reduced in proportion to the ratio selected by our Board of Directors. Thus, the Reverse Stock Split will effectively increase the number of authorized and unissued shares of our common stock available for future issuance by the amount of the reduction effected by the Reverse Stock Split.

Following the Reverse Stock Split, the Board of Directors will have the authority, subject to applicable laws, to issue all authorized and unissued shares without further stockholder approval, upon such terms and conditions as the Board of Directors deems appropriate. We currently do not have any plans, proposals or understandings to issue the additional shares that would be available if the Reverse Stock Split is approved and effected.

Effects of a Reverse Stock Split on Outstanding Warrants

Based upon the Reverse Stock Split Ratio, the Reverse Stock Split will require that proportionate adjustments be made to the number of shares of common stock issuable upon exercise of the Company's outstanding warrants such that the number of outstanding warrants/shares of common stock exercisable for those warrants would be proportionally reduced and the exercise price by which the Company's outstanding warrants may be exercised for common stock would be proportionally increased so that the aggregate exercise price of the warrants is unchanged.

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Effects of the Reverse Stock Split on Outstanding Equity Awards and Plans

The Reverse Stock Split would reduce the number of shares of common stock available for issuance under our 2019 Equity Incentive Plan or the 2019 Plan, our 2019 Employee Stock Purchase Plan or the ESPP, our 2022 Inducement Plan, and the Novosteo 2019 Equity Incentive Plan, in proportion to the reverse split ratio of the Reverse Stock Split.

Similarly, under the terms of the 2019 Plan and the agreements governing the Company's outstanding stock options, the Reverse Stock Split will effect a reduction in the number of shares of the Company's common stock issuable upon the vesting of such stock options in proportion to the reverse split ratio of the Reverse Stock Split. In connection with the Reverse Stock Split, the number of shares of the Company's common stock issuable upon the vesting of outstanding stock options will be rounded up to the nearest whole share, and no cash payment will be made in respect of such rounding.

Effects of the Reverse Stock Split on Voting Rights

Proportionate voting rights and other rights of the holders of common stock would not be affected by the Reverse Stock Split (other than as a result of the treatment of fractional shares). For example, a holder of 1% of the voting power of the outstanding common stock immediately prior to the effective time of the Reverse Stock Split would continue to hold 1% of the voting power of the outstanding common stock immediately after the Reverse Stock Split.

Effects of the Reverse Stock Split on Regulatory Matters

The Company is subject to the periodic reporting and other requirements of the Exchange Act. The Reverse Stock Split will not affect our obligation to publicly file financial and other information with the U.S. Securities and Exchange Commission (the "SEC").

Effects of the Reverse Stock Split on Authorized Share Capital

The total number of shares of capital stock that we are authorized to issue will not be affected by the Reverse Stock Split.

Accounting Matters

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

Treatment of Fractional Shares in the Reverse Stock Split

The Company does not intend to issue fractional shares in the event that a stockholder owns a number of shares of common stock that is not evenly divisible by the reverse stock split ratio chosen by our Board. If the Reverse Stock Split implemented, each fractional share of common stock will be:

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Certain Risks Associated with the Reverse Stock Split

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

Potential Anti-Takeover Effect of the Reverse Stock Split

Upon effectiveness of the Reverse Stock Split, the number of authorized shares of common stock that are not issued or outstanding will increase relative to the number of shares of common stock that are issued and outstanding prior to the Reverse Stock Split. While this increase could, under certain circumstances, have an anti-takeover effect (for example, by permitting issuances that would dilute the stock ownership of a person seeking to effect a change in the composition of the Board or contemplating a tender offer or other transaction for the combination of Quince with another company), Proposal One is not being proposed in response to any effort of which we are aware to accumulate shares of the common stock or to obtain control of Quince.

Effective Date

If our stockholders approve the Reverse Stock Split, the Reverse Stock Split would become effective at such time as it is deemed by our board of directors to be in the best interests of Quince and our stockholders and we file the Certificate of Amendment. Even if the Reverse Stock Split is approved by our stockholders, our board of directors has discretion not to

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carry out or to delay in carrying out the Reverse Stock Split. Upon the filing of the amendment, all of the pre-Reverse Stock Split shares will be converted into new common stock as set forth in the amendment.

Exchange of Stock Certificates

Some stockholders hold their shares of common stock in certificate form or a combination of certificate and book-entry form. Our transfer agent will act as the "exchange agent" for purposes of implementing the exchange of stock certificates. Stockholders holding pre-split shares that are certificated will be asked to surrender to the exchange agent certificates representing pre-split shares in exchange for certificates representing post-split shares in accordance with the procedures to be set forth in a letter of transmittal to be sent by the exchange agent. No new certificates will be issued to a stockholder until such stockholder has surrendered the stockholder's outstanding certificate(s) together with the properly completed and executed letter of transmittal to the exchange agent. Stockholders whose shares are held in book-entry form or by their stockbroker do not need to submit old share certificates for exchange. These stockholders' book-entry records or brokerage accounts will automatically reflect the new quantity of shares based on the selected reverse stock split ratio. As soon as practicable after the Effective Time, our transfer agent will send to such stockholders or their brokers a transmittal letter along with a statement of ownership indicating the number of post-reverse stock split shares of common stock held. Beginning on the effective date of the reverse stock split, each certificate or other share ownership record representing pre-split shares will be deemed for all corporate purposes to evidence ownership of post-split shares.

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

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

The following is a summary of certain material federal income tax consequences of the Reverse Stock Split that generally are expected to be applicable to U.S. Holders (as defined below) of our common stock who hold their common shares as capital assets within the meaning of Section 1221 of Internal Revenue Code of 1986, as amended (the "Code") (generally property held for investment). This summary is based on the provisions of the Code, applicable Treasury Regulations promulgated thereunder, judicial authorities and current administrative rulings and practices as in effect on the date of this proxy statement. Changes to these laws could alter the tax consequences described below, possibly with retroactive effect, which may result in the U.S. federal income tax consequences of the Reverse Stock Split differing substantially from the consequences summarized below. We have not sought and will not seek an opinion of counsel or a ruling from the Internal Revenue Service regarding the U.S. federal income tax consequences of the Reverse Stock Split, and there can be no assurance that the Internal Revenue Service or the courts will agree with the positions expressed below.

This summary is for general information purposes only and does not purport to consider all aspects of U.S. federal income taxation that might be relevant to a U.S. Holder in light of their particular circumstances or to holders that are subject to special tax rules, including without limitation banks, financial institutions, insurance companies, regulated investment companies, mutual funds, real estate investment trusts, personal holding companies, foreign entities, nonresident alien individuals, broker-dealers, traders, tax-exempt entities, persons who hold their pre-reverse split shares as a position in a hedging transaction, "straddle," "conversion transaction" or other integrated or risk reduction transaction, persons whose pre-reverse split shares constitute qualified small business stock within the meaning of Section 1202 of the Code, holders who hold their pre-reverse split shares through individual retirement or other tax-deferred accounts, holders of common stock who are not U.S. Holders (as defined below), holders pre-reverse split shares who have a functional currency for U.S. federal income tax purposes other than the U.S. dollar, holders who acquired their pre-reverse split shares in a transaction subject to the gain rollover provisions of Section 1045 of the Code, holders who acquired their pre-reverse split shares pursuant to the exercise of employee stock options or otherwise as compensation, or holders of pre-reverse split shares who are partnerships, limited liability companies that are not treated as corporations for U.S. federal income tax purposes, S corporations, or other pass-through entities or investors in such pass-through entities. In addition, this summary does not discuss the tax consequences of the Reverse Stock Split under state, local, non-U.S. laws or under gift, excise or other federal non-income tax laws, or the application of the alternative minimum tax rules, the Medicare contribution tax on net

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investment income or the special tax accounting rules under Section 451(b) of the Code. This summary does not address the tax consequences of transactions effectuated prior or subsequent to, or concurrently with, the Reverse Stock Split (whether or not any such transactions are consummated in connection with the Reverse Stock Split), or the tax consequences to holders of options, warrants or similar rights to acquire common stock.

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

Tax Consequences of the Reverse Stock Split

The Reverse Stock Split should constitute a "recapitalization" for U.S. federal income tax purposes. In general, the federal income tax consequences of a Reverse Stock Split will vary depending upon whether a U.S. Holder receives cash for fractional shares or solely a reduced number of shares of common stock in exchange for their pre-Reverse Stock Split shares. We believe that because the Reverse Stock Split is not part of a plan to increase periodically a stockholder's proportionate interest in our assets or earnings and profits, the Reverse Stock Split should have the following federal income tax effects. A U.S. Holder that receives solely a reduced number of shares of common stock generally will not recognize gain or loss in the Reverse Stock Split. A U.S. Holder's aggregate tax basis in the reduced number of shares of common stock should equal the U.S. Holder's aggregate tax basis in its pre-Reverse Stock Split shares of common stock, and such U.S. Holder's holding period in the reduced number of shares of common stock should include the holding period in its pre-Reverse Stock Split shares of common stock exchanged. Treasury Regulations provide detailed rules for allocating the tax basis and holding period of the shares of common stock surrendered to the shares of common stock received in a recapitalization such as the Reverse Stock Split. U.S. Holders should consult their tax advisors as to application of the foregoing rules where shares of pre-Reverse Stock Split common stock were acquired at different times or at different prices.

As noted above, we will not issue fractional shares of common stock in connection with the implementation of the reverse stock split ratios set forth in the Reverse Stock Split. In certain circumstances, stockholders who would be entitled to receive fractional shares of common stock because they hold a number of shares not evenly divisible by the reverse stock split ratio chosen by our Board will automatically be entitled to receive an additional fraction of a share of common stock to round up to the next whole post-reverse stock split share of common stock. The U.S. federal income tax consequences of the receipt of such an additional fraction of a share of common stock is not clear.

The tax treatment of a stockholder may vary depending upon the particular facts and circumstances of such stockholder. Each stockholder is urged to consult with such stockholder's own tax advisor with respect to the tax consequences of a reverse stock split.

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

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No Dissenters' Rights

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

OUR BOARD OF DIRECTORS RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL ONE.

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PROPOSAL TWO: RATIFICATION OF SELECTION OF INDEPENDENT REGISTERED PUBLIC ACCOUNTING FIRM

Our audit committee has selected BDO USA, P.C. as the Company's independent registered public accounting firm for the fiscal year ending December 31, 2026 and has further directed that management submit the selection of its independent registered public accounting firm for ratification by the stockholders at the Annual Meeting. BDO USA, P.C. has audited the Company's financial statements since 2018. Representatives of BDO USA, P.C. are expected to be present at the annual meeting. They will have an opportunity to make a statement if they so desire and will be available to respond to appropriate questions.

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

Independent Registered Public Accounting Firm Fees and Services

The following table represents aggregate fees billed to the Company for the fiscal years ended December 31, 2025 and December 31, 2024, by BDO USA, P.C., the Company's principal accountant:

All fees described above were pre-approved by our audit committee.

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

Our Audit Committee's policy is to pre-approve all audit and permissible non-audit services provided by our independent registered public accounting firm, the scope of services provided by our independent registered public accounting firm and the fees for the services to be performed. These services may include audit services, audit-related services, tax services and other services. Pre-approval is detailed as to the particular service or category of services and is generally subject to a specific budget. The Audit Committee or its Chair, whom the Audit Committee has designated as a one-person subcommittee with pre-approval authority, pre-approved all audit fees, audit-related fees, tax fees and other fees in 2025 and 2024. Any pre-approvals by the subcommittee must be and were presented to the Audit Committee at its next

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scheduled meeting. Our independent registered public accounting firm and management are required to periodically report to the Audit Committee regarding the extent of services provided by our independent registered public accounting firm in accordance with this pre-approval, and the fees for the services performed to date.

OUR BOARD OF DIRECTORS RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL TWO.

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PROPOSAL THREE: ADVISORY VOTE ON THE COMPENSATION OF THE NAMED EXECUTIVE OFFICERS

Under the Dodd-Frank Wall Street Reform and Consumer Protection Act or the Dodd-Frank Act, and Section 14A of the Exchange Act, the Company's stockholders are entitled to vote to approve, on an advisory basis, the compensation of the Company's named executive officers as disclosed in this Proxy Statement in accordance with SEC rules. This vote is not intended to address any specific item of compensation, but rather the overall compensation of our named executive officers and the philosophy, policies and practices described in this Proxy Statement.

The compensation of our named executive officers subject to the vote is disclosed in "Executive Compensation," and the compensation tables and the related narrative disclosure contained in this Proxy Statement.

Accordingly, the Board recommends that our stockholders vote FOR the following resolution:

"RESOLVED, that the compensation paid to our named executive officers, as disclosed pursuant to Item 402 of Regulation S-K, including the compensation tables and narrative discussion, is hereby APPROVED."

Because the vote is advisory, it is not binding on the Board or on us. Nevertheless, the views expressed by our stockholders, whether through this vote or otherwise, are important to management and the Board and, accordingly, the compensation committee and Board intend to consider the results of this vote in making determinations in the future regarding executive compensation arrangements. Your vote will serve as an additional tool to guide the compensation committee and Board in continuing to improve the alignment of our executive compensation programs with business objectives and performance and with the interests of our stockholders. Unless the Board decides to modify its policy regarding the frequency of soliciting say-on-pay votes, the next scheduled say-on-pay vote will be at the 2027 Annual Meeting of Stockholders.

OUR BOARD OF DIRECTORS RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL THREE.

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PROPOSAL FOUR: ADJOURNMENT OR POSTPONEMENT OF ANNUAL MEETING

General

This Proposal Four, if adopted, will allow the chairman of the Annual Meeting to adjourn the Annual Meeting to a later date or dates to permit further solicitation of proxies. This proposal will only be presented to you in the event that there are insufficient votes for, or otherwise in connection with, the approval of the other proposal presented at the Annual Meeting.

Consequences if the Adjournment Proposal is Not Approved

If this proposal is not approved by our stockholders, we will not be able to adjourn the Annual Meeting to a later date or dates in the event that there are insufficient votes for, or otherwise in connection with, the approval of the other proposal presented at the Annual Meeting.

OUR BOARD OF DIRECTORS RECOMMENDS A VOTE "FOR" APPROVAL OF PROPOSAL FOUR.

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SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

The following table sets forth certain information with respect to the beneficial ownership of our common stock as of April 10, 2026 by:

Beneficial ownership is determined in accordance with the rules of the SEC and generally includes any shares over which a person exercises sole or shared voting or investment power. Unless otherwise indicated below, to our knowledge, the persons and entities named in the table have sole voting and sole investment power with respect to all shares beneficially owned by them, subject to community property laws where applicable. Shares of our common stock subject to stock options that are currently exercisable or exercisable within 60 days of April 10, 2026 are deemed to be outstanding and to be beneficially owned by the person holding the stock options for the purpose of computing the percentage ownership of that person, but are not treated as outstanding for the purpose of computing the percentage ownership of any other person.

On April 10, 2026, we effected a reverse stock split by means of a one-for-ten (1-for-10) reverse split of its outstanding common stock, which resulted in a decrease in outstanding common stock to approximately 16,300,794 shares immediately after the reverse stock split. The reverse stock split became effective as of 11:59 p.m., Eastern Time, on April 10, 2026 and our common stock began trading on the Nasdaq Stock Market on a split-adjusted basis on April 13, 2026. We have retroactively adjusted all share amounts and per share data in this proxy statement to give effect to such reverse stock split. However, the information set forth in our Annual Report on Form 10-K for the year ended December 31, 2025 has not been adjusted to give effect to such reverse stock split.

Percentage ownership of our common stock is based on 16,300,794 shares of our common stock outstanding on April 10, 2026. Unless otherwise indicated, the address of each of the individuals and entities named below is c/o Quince Therapeutics, Inc., 611 Gateway Boulevard, Suite 273, South San Francisco, California 94080.

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EXECUTIVE OFFICERS

The following table sets forth certain information regarding our executive officers as of April 23, 2026.

Dirk Thye, M.D. For a brief biography of Dr. Thye, please see "Directors Continuing in Office Until the 2027 Annual Meeting" above.

Charles Ryan, Ph.D. has served as our President since September 2023. In February 2026, Dr. Ryan became a member of the board of directors of Polaryx Therapeutics, Inc. From May 2021 to October 2022, Dr. Ryan served as President, Chief Executive Officer, and Chairman of Travecta Therapeutics, a private biopharmaceutical company pioneering transformative treatments for serious neurological conditions and from December 2017 to December 2022, he served as Chief Executive Officer and Director of Neurotrope, Inc., a clinical-stage biopharmaceutical company developing targeted, novel regenerative therapeutics for neurodegenerative diseases and developmental disorders. Prior to that, he served as Senior Vice President and Chief Intellectual Property Counsel at Forest Laboratories (now AbbVie) for more than 10 years where he managed several intellectual property estates spanning CNS, cardiovascular, gastrointestinal, respiratory, and anti-infective therapeutic areas. He also worked closely with the commercial and development teams, as well as the business development teams at Forest. Dr. Ryan holds a J.D. from Western New England University, a Ph.D. in Oral Biology and Pathology from Stony Brook University, and a B.A. in Chemistry from The College of Wooster. He is a member of the New York State Bar and is a patent practitioner of the U.S. Patent and Trademark Office.

Brendan Hannah has served as our Chief Business Officer since May 2022 and was appointed as our Chief Compliance Officer in March 2023 and our Chief Operating Officer in October 2023. Previously, Mr. Hannah served as the Chief Operating Officer of Novosteo Inc., a biopharmaceutical company, from November 2021 to May 2022. Previously, from January 2019 to October 2021, Mr. Hannah was the Chief Business Officer of Neuroptika, Inc., a biopharmaceutical company, and from January 2017 to March 2020, the Vice President of Operations and Strategy of Geom Therapeutics, a biopharmaceutical company. Mr. Hannah holds an M.B.A. from the University of California, Los Angeles Anderson School of Management and a B.A. in Economics from Colorado College.

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EXECUTIVE COMPENSATION

Our named executive officers ("NEOs") for fiscal 2026 consisted of the following individuals:

SUMMARY COMPENSATION TABLE

The following table sets forth all of the compensation awarded to, earned by, or paid to each of the NEOs for their services rendered for the years ended December 31, 2025 and 2024.

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OUTSTANDING EQUITY AWARDS

The following table provides information regarding outstanding equity awards held by each of our NEOs as of December 31, 2025.

* Issued and outstanding options for shares of common stock have been adjusted for the periods prior to April 10, 2026, to reflect the 1-for-10 reverse stock split effected on that date on a retroactive basis.

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NARRATIVE TO SUMMARY COMPENSATION TABLE AND OUTSTANDING EQUITY AWARDS TABLE

Our executive compensation program generally consists of, and is intended to strike a balance among, the following three principal components: base salary, annual performance-based bonuses, and long-term incentive compensation. We also provide our executive officers with severance and change-in-control benefits, as well as other benefits available to all our employees, including retirement benefits under the Company's 401(k) plan and participation in employee benefit plans.

Executive Incentive Bonus Plan

Each of our NEOs is eligible to participate in our Executive Incentive Bonus Plan ("Bonus Plan"). The purpose of the Bonus Plan is to motivate and reward eligible officers and other designated employees for their contributions toward the achievement of certain performance goals. Each NEO is eligible to receive a performance bonus based on (1) the individual's target bonus, as a percentage of base salary, and (2) the percentage attainment of performance goals established by the compensation committee. For 2025, the targets for each Named Executive Officer, as a percentage of base salary, were as follows: 50% for Dr. Thye, 40% for Dr. Ryan, and 40% for Mr. Hannah. On January 23, 2026, the compensation committee determined that 107.5% of the corporate objectives were achieved for 2025 and therefore each of Dr. Thye, Dr. Ryan, and Mr. Hannah were entitled to be paid out bonuses at 107.5% of the corporate goal achievement.

Long-Term Incentives

On January 28, 2025, Dr. Thye, Dr. Ryan, and Mr. Hannah received options to purchase 120,000, 30,000, and 45,000 shares of common stock, respectively, with an exercise price of $16.00 per share. The options vest in equal monthly installments over a four-year period beginning on January 1, 2025, subject to the NEOs' continuous service with the Company through each applicable vesting date.

Employment Agreements and Separation Agreements with Our NEOs

We have offer letter agreements and separation agreements with each of our NEOs. The agreements generally provide for at-will employment and set forth the executive officer's initial base salary, annual performance bonus opportunity, initial equity grant amount and eligibility for employee benefits. The key terms of the offer letters are described below.

Dirk Thye, M.D.

In May 2022, we entered into an offer letter with Dr. Thye, our current Chief Executive Officer and Chief Medical Officer. The offer letter has no specific term and provides for at-will employment. Dr. Thye's annual base salary was $550,000 for fiscal year 2025. Dr. Thye is also eligible to earn a discretionary annual bonus based on achievement of specified performance goals. Dr. Thye's target bonus was 50% of his annual base salary for fiscal year 2025.

The Company and Dr. Thye entered into an executive change in control and severance agreement, or the Thye Severance Agreement. For a summary of the material terms of the Thye Severance Agreement, see "-Potential Payments Upon Termination or Change of Control" below.

Charles Ryan, Ph.D.

In September 2023, we entered into an offer letter with Dr. Ryan, our current President. The offer letter has no specific term and provides for at-will employment. Dr. Ryan's annual base salary was $500,000 for fiscal year 2025. Dr. Ryan is also eligible to earn a discretionary annual bonus based on achievement of specified performance goals. Dr. Ryan's target bonus was 40% of his annual base salary for fiscal year 2025. In addition, Dr. Ryan is eligible for a monthly cash stipend of $1,800 to assist in covering the cost of his health insurance premium or other medical expenses.

In connection with the commencement of his employment with the Company, the Company granted Dr. Ryan an option to purchase 54,500 shares of the Company's common stock (the "Ryan Option") pursuant to the 2019 Plan, with an exercise

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price equal to the fair market value of the Company's common stock on the grant date. 25% of the shares subject to the Ryan Option will vest one year after the date of the grant and the remaining shares will vest in equal monthly installments over the following three years thereafter, subject to Dr. Ryan's continuous service with the Company through each applicable vesting date.

The Company and Dr. Ryan entered into an executive change in control and severance agreement or the Ryan Severance Agreement. The Ryan Severance Agreement provides for severance benefits upon a qualifying termination of employment, including modified severance benefits on a qualifying termination of employment in connection with a change in control. For a summary of the material terms of the Ryan Severance Agreement, see "-Potential Payments Upon Termination or Change of Control" below.

Brendan Hannah

In May 2022, we entered into an offer letter with Mr. Hannah, our current Chief Operating Officer and Chief Business Officer. The offer letter has no specific term and provides for at-will employment. Mr. Hannah's annual base salary was $455,000 for fiscal year 2025. Mr. Hannah is also eligible to earn a discretionary annual bonus based on achievement of specified performance goals. Mr. Hannah's target bonus was 40% of his annual base salary for fiscal year 2025.

The Company and Mr. Hannah entered into an executive change in control and severance agreement, or the Hannah Severance Agreement. For a summary of the material terms of the Hannah Severance Agreement, see "-Potential Payments Upon Termination or Change of Control" below.

Welfare and Health Benefits

Our named executive officers are eligible to participate in all of our benefit plans, such as the 401(k) plan (see description under "401(k) Plan" below), medical, dental, vision, short-term disability, long-term disability and group life insurance, in each case generally on the same basis as other employees. We do not currently have qualified or nonqualified defined benefit plans or nonqualified deferred compensation plans, nor do we offer pension or other retirement benefits other than our 401(k) plan. Our board of directors may elect to adopt such plans in the future if it determines that doing so is in our best interests.

Perquisites and Other Benefits

We generally do not offer perquisites or personal benefits to our NEOs, although we may from time to time provide reasonable relocation, signing bonuses, retention bonuses, or other benefits to our NEOs as our compensation committee determines appropriate.

401(k) Plan

We maintain a tax-qualified retirement plan that provides eligible U.S. employees, including our named executive officers, with an opportunity to save for retirement on a tax-advantaged basis. Eligible employees may make voluntary contributions from their eligible pay, up to certain applicable annual limits set by the Internal Revenue Code of 1986, as amended or the Code. The 401(k) plan is intended to be qualified under Section 401(a) of the Code with the 401(k) plan's related trust intended to be tax exempt under Section 501(a) of the Code.

Historically, we have not made matching contributions into the 401(k) plan on behalf of participants. However, in 2021, we began matching 100% of employee contributions, up to an annual maximum of $4,000 per calendar year for each employee. All such employee contributions and Company matching contributions are immediately and fully vested.

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Clawbacks

As a public company, if we are required to restate our financial results due to our material noncompliance with any financial reporting requirements under the federal securities laws as a result of misconduct, the CEO and Chief Financial Officer may be legally required to reimburse our Company for any bonus or other incentive-based or equity-based compensation they receive in accordance with the provisions of section 304 of the Sarbanes-Oxley Act of 2002, as amended. Additionally, we have implemented a Dodd-Frank Act-compliant clawback policy, as required by SEC rules.

POTENTIAL PAYMENTS UPON TERMINATION OR CHANGE IN CONTROL

We have entered into Severance Agreements or Executive Change in Control and Severance Agreements, or CiC Agreements, with Dr. Thye, Dr. Ryan, and Mr. Hannah, which provide for certain payments and benefits in connection with certain terminations of employment with the Company, including terminations that occur in connection with a change in control (as defined in the CiC Agreements), subject to the named executive officer's execution and non-revocation of a general release of claims in a form prescribed by the Company.

The compensation committee believes that the severance protection benefits we offer are necessary to provide stability among our executive officers, serve to focus our executive officers on our business operations, and avoid distractions in connection with a potential change in control transaction or period of uncertainty.

Under the CiC Agreements, if within the period beginning 3 months prior to, and ending 18 months following, a change in control of the Company, or the CiC Period, the Company terminates a named executive officer's employment without "cause" or a named executive officer resigns for "good reason" (each as defined in the CiC Agreements), the named executive officer will be eligible to receive the following: (i) 18 months of base salary to be paid within thirty (30) days following the Release Deadline (as defined in the CiC Agreements); (ii) an amount equal to 150% of the named executive officer's target annual bonus opportunity for the year in which the termination occurs, pro-rated to the effective date of termination,to be paid in a single lump-sum within thirty (30) days following the Release Deadline; (iii) full vesting acceleration of any then-outstanding unvested equity awards that are subject to time-based vesting and vesting at 100% of target levels of any then-outstanding unvested equity awards that are subject to performance-based vesting, as of the later of the named executive officer's termination of employment of the change in control; and (iv) a cash payment equal to 18 months of COBRA premiums to be paid in a single lump-sum within thirty (30) days following the Release Deadline.

In addition, the CiC Agreements provide that if the Company terminates a named executive officer's employment without cause or a named executive officer resigns for "good reason" outside of the CiC Period, the named executive officer will be eligible to receive the following: (i) 12 months of base salary; (ii) an amount equal to 100% of the named executive officer's target annual bonus opportunity for the year in which the termination occurs, pro-rated to the effective date of termination,to be paid in a single lump-sum within thirty (30) days following termination of employment; (iii) vesting acceleration of 50% of any then-outstanding unvested equity awards that are subject to time-based vesting and vesting at 50% of target levels of any then-outstanding unvested equity awards that are subject to performance-based vesting as of the named executive officer's termination of employment; and (iv) a cash payment equal to 12 months of COBRA premiums to be paid in a single lump-sum within thirty (30) days following the Release Deadline. The base salary severance will be paid to named executive officer at named executive officer's Base Salary Rate (as defined in the CiC Agreements) in accordance with the Company's normal payroll practices on the Company's regularly scheduled payroll dates commencing with the first regularly scheduled payroll date that occurs at least 8 days following termination of employment, with the first payment being equal to the number of business days between named executive officer's last day of employment and the date of the first payment multiplied by named executive officer's daily Base Salary Rate.

Pursuant to the CiC Agreements, in the event of a change in control, if our successor does not agree to assume, substitute or otherwise continue any then outstanding stock options, the vesting of the unvested stock options shall accelerate in full (or, with respect to performance-based options, at 100% of target level), effective immediately prior to and contingent upon a change of control, unless our named executive officer resigns without good reason or is terminated for cause.

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In addition, if any of the payments or benefits provided to a named executive officer constitutes a parachute payment under Section 280G of the Code, the payments or benefits may be reduced so that no portion of the payment is subject to the excise tax imposed under Section 4999 of the Code.

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Compensation Actually Paid and Net Income (Loss)

The following graph sets forth the relationship between Compensation Actually Paid to our PEO, the average of Compensation Actually Paid to our Non-PEO NEOs, and the Company's net income (loss) over the three most recently completed fiscal years.

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Policies and Practices Related to the Grant of Certain Equity Awards Close in Time to the Release of Material Nonpublic Information

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DIRECTOR COMPENSATION

Director Compensation Table

The following table provides information concerning compensation awarded to, earned by and paid to each person who served as a non-employee member of our board of directors during the fiscal year ended December 31, 2025. Dr. Thye is not included in the table below, as he was employed in 2025 as our Chief Executive Officer and Chief Medical Officer, and received no additional compensation for his service as director. The compensation received by Dr. Thye is shown in "Executive Compensation-Summary Compensation Table" above.

* Issued and outstanding options for shares of common stock have been adjusted for the periods prior to April 10, 2026, to reflect the 1-for-10 reverse stock split effected on that date on a retroactive basis.

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Non-Employee Director Compensation Arrangements

Pursuant to our outside director compensation policy adopted by our board of directors on June 7, 2022, as amended and restated on December 2, 2024 (the "Outside Director Compensation Policy"), we pay each non-employee director an annual cash retainer for service on the board of directors and an additional annual cash retainer for service on each committee on which the director is a member, which is paid quarterly in arrears. Our Lead Independent Director. Chairperson of the board of directors, and the chair of each committee will receive higher annual cash retainers for such service. Each director may elect to receive all of the annual cash retainer, beginning with the annual cash retainer to be received on and after January 1, 2025, in the form of a stock option, which will vest in substantially equal quarterly installments on the last day of each quarter, subject to the director's continued service through such date. The fees paid to non-employee directors for service on the board of directors and for service on each committee of the board of directors of which the director is a member are as follows:

Pursuant to our Outside Director Compensation Policy, each non-employee director who is appointed to our board of directors shall initially be granted a stock option to purchase 5,400 shares of our common stock.

One-third of the shares subject to such initial stock option grant will vest on each of the first, second and third anniversaries of the date of grant, subject to the director's continued service as a member of our board of directors through each vesting date. Further, at the close of business on the date of each annual meeting of stockholders, each continuing non-employee director will be granted a stock option to purchase the total shares of our common stock set forth below:

100% of the shares subject to any such annual stock option grant will vest in full on the one-year anniversary of the grant date, subject to the director's continued service as a member of our board of directors through the vesting date.

All stock options granted to non-employee directors will be made pursuant to our 2019 Plan and will vest in full immediately prior to, and contingent upon, the consummation of a change in control of our Company, subject to the director's continued service as a member of our board of directors through the change in control.

We also reimburse our directors for their reasonable out-of-pocket expenses in connection with attending meetings of our board of directors and committees.

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The non-employee director compensation program is intended to provide a total compensation package that enables us to attract and retain qualified and experienced individuals to serve as directors and to align our directors' interests with those of our stockholders.

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EQUITY COMPENSATION PLAN INFORMATION

The following table presents information as of December 31, 2025 with respect to all of the Company's equity compensation plans under which shares of our common stock may be issued.

* Issued and outstanding options, warrants and rights for shares of common stock have been adjusted for the periods prior to April 10, 2026, to reflect the 1-for-10 reverse stock split effected on that date on a retroactive basis.

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CERTAIN RELATIONSHIPS AND RELATED PARTY TRANSACTIONS

There has been no transaction since January 1, 2024, or any currently proposed transaction, in which the Company was or are to be a participant and the amount involved exceeded or exceeds the lesser of $120,000 or one percent of the average of the total assets of the Company at year-end for the last two completed fiscal years, and in which any related person had or will have a direct or indirect material interest.

Indemnification Agreements

Our amended and restated certificate of incorporation contains provisions limiting the liability of directors, and our amended and restated bylaws provide that we will indemnify each of our directors and executive officers to the fullest extent permitted under Delaware law. In addition, we have entered into an indemnification agreement with each of our directors and executive officers, which requires us to indemnify them in certain circumstances.

Review, Approval or Ratification of Transactions with Related Parties

Our written related party transactions policy states that our executive officers, directors, nominees for election as a director, beneficial owners of more than 5% of our common stock and any members of the immediate family of and any entity affiliated with any of the foregoing persons are not permitted to enter into a related party transaction with us without the review and approval of our audit committee (or our nominating and corporate governance committee in the event it is inappropriate for our audit committee to review such transaction due to a conflict of interest). The policy provides that any request for us to enter into a transaction with an executive officer, director, nominee for election as a director, beneficial owner of more than 5% of our common stock or with any of their immediate family members or affiliates in which the amount involved exceeds $120,000 must be presented to our audit committee (or our nominating and corporate governance committee in the event it is inappropriate for our audit committee to review such transaction due to a conflict of interest) for review, consideration and approval. In approving or rejecting any such proposal, our audit committee (or our nominating and corporate governance committee in the event it is inappropriate for our audit committee to review such transaction due to a conflict of interest) considers the relevant facts and circumstances available and deemed relevant to the committee, including, but not limited to, whether the transaction is on terms no less favorable than terms generally available to an unaffiliated third party under the same or similar circumstances and the extent of the related party's interest in the transaction.

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HOUSEHOLDING OF PROXY MATERIALS

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for Notices of Internet Availability of Proxy Materials or other Annual Meeting materials with respect to two or more stockholders sharing the same address by delivering a single Notice of Internet Availability of Proxy Materials or other Annual Meeting materials addressed to those stockholders. This process, which is commonly referred to as "householding," potentially means extra convenience for stockholders and cost savings for companies.

This year, a number of brokers with account holders who are Quince Therapeutics, Inc. stockholders will be "householding" the Company's proxy materials. A single Notice of Internet Availability of Proxy Materials will be delivered to multiple stockholders sharing an address unless contrary instructions have been received from the affected stockholders. Once you have received notice from your broker that they will be "householding" communications to your address, "householding" will continue until you are notified otherwise or until you revoke your consent. If, at any time, you no longer wish to participate in "householding" and would prefer to receive a separate Notice of Internet Availability of Proxy Materials, please notify your broker or Quince. Direct your written request to Quince Therapeutics, Inc., Attn: Investor Relations, 611 Gateway Boulevard, Suite 273, South San Francisco, California 94080 or contact us at (415) 910-5717. Stockholders who currently receive multiple copies of the Notices of Internet Availability of Proxy Materials at their addresses and would like to request "householding" of their communications should contact their brokers.

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ADDITIONAL INFORMATION

We will mail, without charge, upon written request, a copy of our annual report on Form 10-K for the fiscal year ended December 31, 2025, including the financial statements and list of exhibits, and any exhibit specifically requested. Requests should be sent to:

Quince Therapeutics, Inc.

611 Gateway Boulevard, Suite 273

South San Francisco, California

94080 Attn: Investor Relations

Our annual report on Form 10-K for the fiscal year ended December 31, 2025 is also available at https://ir.quincetx.com/investor-relations under "SEC Filings" in the "Financial Information" section of our website and at http://www.astproxyportal.com/ast/22818.

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Appendix A

Form of Amendment to Amended and Restated Certificate of Incorporation with Respect to Proposal 1

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CERTIFICATE OF AMENDMENT TO

THE AMENDED AND RESTATED CERTIFICATE OF INCORPORATION

OF

QUINCE THERAPEUTICS, INC.

Quince Therapeutics, Inc., a corporation organized and existing under the laws of the State of Delaware (the "Corporation"), does hereby certify as follows:

Article IV, Section 1 of the Amended and Restated Certificate is hereby amended and restated to read in its entirety as follows:

"ARTICLE IV

Section 1. The total number of shares of all classes of stock that the Corporation has authority to issue is 260,000,000 shares, consisting of two classes: 250,000,000 shares of Common Stock, $0.001 par value per share ("Common Stock"), and 10,000,000 shares of Preferred Stock, $0.001 par value per share ("Preferred Stock").

Effective as of 5:00 p.m. Eastern time, on the date this Certificate of Amendment to this Amended and Restated Certificate of Incorporation is filed with the Secretary of State of the State of Delaware (the "Effective Time"), each [ ( )] shares of the Corporation's Common Stock, par value $0.001 per share, issued and outstanding shall be combined into one share of Common Stock, par value $0.001 per share (the "Old Common Stock"), either issued or outstanding, immediately prior to the Effective Time, will be automatically reclassified and combined (without any further act) into a smaller number of shares such that each [ ] shares of Old Common Stock issued and outstanding immediately prior to the Effective Time is reclassified into [ ] share of Common Stock, $0.0001 par value per share, of the Corporation (the "New Common Stock"), without increasing or decreasing the amount of stated capital or paid-in surplus of the Corporation (the "Reverse Stock Split"). The Board of Directors shall make provision for the issuance of that number of fractions of New Common Stock such that any fractional share of a holder otherwise resulting from the Reverse Stock Split shall be rounded up to the next whole number of shares of New Common Stock. Any stock certificate that, immediately prior to the Effective Time, represented shares of the Old Common Stock will, from and after the Effective Time, automatically and without the necessity of presenting the same for exchange, represent the number of shares of the New Common Stock into which such shares of Old Common Stock shall have been reclassified plus the fraction, if any, of a share of New Common Stock issued as aforesaid.

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IN WITNESS WHEREOF, Quince Therapeutics, Inc. has caused this Certificate of Amendment to be signed by a duly authorized officer of the Corporation on     , 2026.

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Preliminary Proxy-Subject To Completion

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