Acer Therapeutics (ACER) DEF 14A Definitive proxy

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934

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

Check the appropriate box:

☐	Preliminary Proxy Statement
☐	Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2))
☒	Definitive Proxy Statement
☐	Definitive Additional Materials
☐	Soliciting Material Pursuant to ss. 240.14a-12

Acer Therapeutics Inc.

(Name of Registrant as Specified in its Charter)

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

Payment of Filing Fee (Check the appropriate box):

☒	No fee required.
☐	Fee computed on table below per Exchange Act Rules 14a-6(i)(1) and 0-11.
	(1)	Title of each class of securities to which transaction applies:
	(2)	Aggregate number of securities to which transaction applies:
	(3)	Per unit price or other underlying value of transaction computed pursuant to Exchange Act Rule 0-11 (set forth the amount on which the filing fee is calculated and state how it was determined):
	(4)	Proposed maximum aggregate value of transaction:
	(5)	Total fee paid:
☐	Fee paid previously with preliminary materials.
☐	Check box if any part of the fee is offset as provided by Exchange Act Rule 0-11(a)(2) and identify the filing for which the offsetting fee was paid previously. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.
	(1)	Amount Previously Paid:
	(2)	Form, Schedule or Registration Statement No.:
	(3)	Filing Party:
	(4)	Date Filed:

ACER THERAPEUTICS INC.

ONE GATEWAY CENTER, SUITE 351

300 WASHINGTON STREET

NEWTON, MASSACHUSETTS 02458

October 14, 2020

To Our Stockholders:

You are cordially invited to attend the Annual Meeting of Stockholders of Acer Therapeutics Inc. on Thursday, November 19, 2020 at 10:00 a.m. Eastern Time. In light of the ongoing developments related to the COVID-19 pandemic and to protect the health of our employees, stockholders and the community, the Annual Meeting will be a completely virtual meeting of stockholders conducted via live audio webcast. You will be able to attend the Annual Meeting via the Internet at https://www.cstproxy.com/acertx/2020 by using the control number which appears on your proxy card and the instructions that accompany your proxy materials.

It is important that your shares be represented and voted at the virtual meeting. Whether or not you plan to attend the Annual Meeting, please complete, sign, date, and promptly return the accompanying proxy in the enclosed envelope or use one of the voting methods described in the attached materials. Returning the proxy does NOT deprive you of your right to attend the Annual Meeting. If you decide to attend the Annual Meeting and wish to change your proxy vote, you may do so automatically by voting electronically at the meeting. Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to attend and vote at the meeting, you must obtain from the record holder a legal proxy issued in your name.

Sincerely yours,

Chris Schelling, President and Chief Executive Officer

If you need additional copies of this Proxy Statement or the enclosed proxy card, or if you have other

questions about the proposals or how to vote your shares, you may contact our proxy solicitor:

ADVANTAGE PROXY

(877) 870-8565 (toll free)

ACER THERAPEUTICS INC.

ONE GATEWAY CENTER, SUITE 351 300 WASHINGTON STREET

NEWTON, MASSACHUSETTS 02458

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD NOVEMBER 19, 2020

The Annual Meeting of stockholders of Acer Therapeutics Inc. (the “Company”) will be held on Thursday, November 19, 2020, at 10:00 a.m. Eastern Time. In light of the ongoing developments related to the COVID-19 pandemic and to protect the health of our employees, stockholders and the community, the Annual Meeting will be a completely virtual meeting of stockholders conducted via live audio webcast. You will be able to attend the Annual Meeting via the Internet at https://www.cstproxy.com/acertx/2020 by using the control number which appears on your proxy card and the instructions that accompany your proxy materials. Stockholders are being asked to vote to:

1. Elect Stephen J. Aselage, Jason Amello, John M. Dunn, Michelle Griffin, and Chris Schelling to the Board of Directors to serve until the next annual meeting of stockholders or until their respective successors have been duly elected and qualified;

2. Ratify the appointment of BDO USA, LLP as our independent auditors for the fiscal year ending December 31, 2020; and

3. Transact any other business properly brought before the Annual Meeting and any adjournment or postponement thereof.

These business items are described more fully in the Proxy Statement accompanying this Notice.

Only stockholders who owned common stock at the close of business on September 30, 2020 can vote at this meeting or any adjournments or postponements that may take place. All stockholders are cordially invited to attend the virtual meeting. However, to assure your representation at the meeting, you are urged to mark, sign and return the enclosed proxy as promptly as possible in the postage-prepaid envelope for that purpose or use one of the voting methods described in the attached materials. Your stock will be voted in accordance with the instructions you have given. Any stockholder attending the virtual meeting may vote electronically even if he or she has previously returned a proxy. Please note, however, that if your shares are held of record by a broker, bank or other nominee and you wish to attend and vote at the meeting, you must obtain from the record holder a legal proxy issued in your name.

By Order of the Board of Directors,

Chris Schelling, President and Chief Executive Officer

Dated: October 14, 2020

The Board of Directors solicits the enclosed proxy. Your vote is important no matter how large or small your stockholdings. To assure your representation at the meeting, please complete, sign, date and promptly mail the enclosed proxy card in the postage-paid envelope provided or use one of the voting methods described in the attached materials.

Important Notice Regarding the Availability of Proxy Materials for the Stockholder Meeting to be held on November 19, 2020: This Proxy Statement and our 2019 Annual Report on Form 10-K are available at https://www.cstproxy.com/acertx/2020

ACER THERAPEUTICS INC.

PROXY STATEMENT

ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD NOVEMBER 19, 2020

INFORMATION CONCERNING SOLICITATION AND VOTING

General

The enclosed proxy is solicited on behalf of our Board of Directors (“Board”) for use at the annual meeting of stockholders to be held on Thursday, November 19, 2020, at 10:00 a.m. Eastern Time (the “Annual Meeting”), or at any adjournment or postponement of the Annual Meeting, for the purposes set forth in this Proxy Statement and in the accompanying Notice of Annual Meeting of Stockholders. The Annual Meeting will be held virtually at https://www.cstproxy.com/acertx/2020. There will be no physical location. The meeting will only be conducted via an audio webcast. We intend to mail this Proxy Statement and accompanying proxy card to stockholders on or about October 14, 2020.

The Board of Acer Therapeutics Inc. prepared this Proxy Statement for the purpose of soliciting proxies for our Annual Meeting of Stockholders. The terms “we,” “our,” the “Company” or “Acer,” refer to Acer Therapeutics Inc., a Delaware corporation. Acer was formerly known as “Opexa Therapeutics, Inc.” prior to the September 19, 2017 merger between Acer (then known as Opexa), Acer Therapeutics Inc., a Delaware corporation (referred to as “Private Acer”), and Opexa Merger Sub, Inc. (the “Merger”).

Availability of Annual Report on Form 10-K

Accompanying this Proxy Statement is our Annual Report on Form 10-K for the fiscal year ended December 31, 2019 as filed with the Securities and Exchange Commission (the “SEC”). We make available, free of charge through our website (www.acertx.com), our annual reports on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Securities Exchange Act of 1934, as amended (the “Exchange Act”), as soon as reasonably practicable after such documents are electronically filed with or furnished to the SEC. These reports can be found under “SEC Filings” through the “Investor Relations” section of our website. We will provide to any stockholder without charge, upon the written request of that stockholder, a copy of our Annual Report on Form 10-K (without exhibits), including financial statements and financial statement schedules. Such requests should be addressed to Investor Relations, Acer Therapeutics Inc., One Gateway Center, Suite 351, 300 Washington Street, Newton, Massachusetts 02458.

Voting

Before the meeting, you may vote your shares if they are registered directly in your name with our transfer agent, Continental Stock Transfer & Trust Company, by (i) completing, signing, dating and returning the enclosed proxy card by mail in the postage paid envelope provided or (ii) using the Internet to vote your proxy 24 hours a day, 7 days a week. If you would like to vote electronically, have your proxy card in hand when you log on and follow the instructions included with your proxy card. You are encouraged to vote electronically by Internet. If you vote by Internet, you do not need to return your proxy card. Please follow the directions on your proxy card carefully. Stockholders are encouraged to vote and submit proxies in advance of the Annual Meeting by Internet or mail as early as possible to avoid COVID-19 related processing delays.

If your shares are held in a brokerage account in the name of a bank, broker or other nominee (this is called “street name”), then you are the beneficial owner of the shares and these proxy materials are being forwarded to

1

you by that organization. The organization holding your account is considered the stockholder of record for purposes of voting at the Annual Meeting. You have the right to direct your bank or broker on how to vote the shares in your account, and you may also be able to vote by telephone or via the Internet depending on the voting procedures used by your broker. You may receive a separate voting instruction form with this Proxy Statement, or you may need to contact your broker, bank or other nominee to determine whether you will be able to vote electronically using the telephone or Internet.

You will be able to attend the virtual Annual Meeting via the Internet at https://www.cstproxy.com/acertx/2020 by using the control number which appears on your proxy card and the instructions that accompany your proxy materials. Whether or not you plan to attend the meeting, however, we encourage you to vote your shares by proxy before the meeting. You may vote your shares at the meeting if you attend online, even if you previously submitted a proxy card or voted by Internet. Please note that if your shares are held in “street name” and you wish to vote at the meeting, you will not be permitted to do so unless you first obtain a legal proxy issued in your name from the broker, bank or nominee that holds your shares.

Revocability of Proxies

Any proxy given pursuant to this solicitation may be revoked by the person giving it at any time before its use by delivering to the Secretary of Acer, at the address of our executive offices noted above, written notice of revocation or a duly executed proxy bearing a later date or by attending the virtual Annual Meeting and voting electronically. Attendance at the virtual Annual Meeting will not, by itself, revoke a proxy.

Quorum, Abstentions and Broker Non-Votes

Only stockholders of record at the close of business on September 30, 2020 (the “Record Date”) will be entitled to notice of and to vote at the virtual Annual Meeting. As of the Record Date, there were 11,912,731 shares of common stock outstanding and entitled to vote. Each holder of record of shares of common stock on the Record Date will be entitled to one vote for each share held on all matters to be voted upon at the Annual Meeting. Shares of common stock may not be voted cumulatively.

Proxies properly executed, duly returned to us and not revoked will be voted in accordance with the specifications made. Where no specifications are given, such proxies will be voted:

• “FOR” each of the five nominees for director; and

• “FOR” ratification of the appointment of our independent auditors.

It is not expected that any matters other than those referred to in this Proxy Statement will be brought before the Annual Meeting. If, however, any matter not described in this Proxy Statement is properly presented for action at the Annual Meeting, the person named as proxy in the enclosed form of proxy will have discretionary authority to vote according to his own discretion.

The required quorum for the transaction of business at the virtual Annual Meeting is a majority of the issued and outstanding shares of our common stock entitled to vote at the Annual Meeting, whether present online or represented by proxy. Our bylaws provide that unless otherwise provided by law or by our Certificate of Incorporation, all matters other than the election of directors shall be decided by the affirmative vote of a majority of the shares of stock represented and present at the Annual Meeting. Shares of common stock represented by a properly signed and returned proxy will be treated as present at the Annual Meeting for purposes of determining a quorum, regardless of whether the proxy is marked as casting a vote or abstaining.

The term “broker non-vote” refers to shares held by a brokerage firm, bank or other nominee (for the benefit of its client) that are represented at the meeting, but with respect to which such broker or nominee is not instructed to vote on a particular proposal and does not have discretionary authority to vote on that proposal.

2

Brokers and nominees do not have discretionary voting authority on certain non-routine matters and accordingly may not vote on such matters absent instructions from the beneficial holder. Discretionary items are proposals considered “routine” under the rules of the New York Stock Exchange (also applicable to Nasdaq-listed companies), such as the ratification of the appointment of our independent auditors. Non-routine items for which brokers and nominees do not have discretionary voting power include the election of directors.

If you hold your shares in street name or through a broker, it is important that you direct your broker how to vote your shares.

Vote Required

Proposal 1. Directors are elected by a plurality of the affirmative votes cast by those shares of common stock present, or represented by proxy, and entitled to vote at the Annual Meeting. This means the five nominees for director receiving the highest number of affirmative votes will be elected. Proxies marked “Withhold Authority” will not affect the election of a candidate who receives a plurality of votes. The election of directors is a matter on which a broker or other nominee is generally not empowered to vote using discretion, and therefore, broker non-votes may exist but will have no effect on the outcome of the election of nominees for director. Stockholders may not cumulate votes in the election of directors. We urge you to provide any necessary voting instructions to your broker or nominee if you hold your shares in street name in order for your vote to be considered for this proposal.

Proposal 2. Approval of Proposal 2 (i.e., the ratification of the appointment of the independent auditors) is a matter on which a broker or other nominee is generally empowered to vote, and therefore, broker non-votes are not expected to exist with respect to this proposal. Abstentions will not affect the outcome.

Attendance at the Virtual 2020 Annual Meeting

After careful consideration, in light of the ongoing developments related to the COVID-19 pandemic and to protect the health of our employees, stockholders and the community, the Annual Meeting will be a completely virtual meeting of stockholders conducted via live audio webcast. In addition, we believe that the virtual meeting format will expand stockholder access and participation. You will not be able to attend the Annual Meeting in person.

The live audio webcast of the 2020 Annual Meeting will begin promptly at 10:00 a.m. Eastern Time. Online access to the audio webcast will open approximately 15 minutes prior to the start of the 2020 Annual Meeting to allow time for our stockholders to log in and test their device audio system. We encourage our stockholders to access the meeting in advance of the designated start time.

To attend the 2020 Annual Meeting, stockholders will need to log-in to https://www.cstproxy.com/acertx/2020 by using the control number which appears on your proxy card and the instructions that accompany your proxy materials.

Submission of Questions at the Virtual 2020 Annual Meeting

An online portal will be available to our stockholders at https://www.cstproxy.com/acertxt/2020 at the 2020 Annual Meeting. By accessing this portal, stockholders will be able to submit questions and vote at the 2020 Annual Meeting. Stockholders may also submit questions and vote on the day of, or during, the 2020 Annual Meeting at https://www.cstproxy.com/acertx/2020. To demonstrate proof of stock ownership, you will need to enter the control number on your proxy card to submit questions and vote at our 2020 Annual Meeting. We intend to answer questions submitted during the meeting that are pertinent to the Company and the items being brought before stockholder vote at the 2020 Annual Meeting, as time permits. Questions and answers will be grouped by topic and substantially similar questions will be answered only once.

3

Technical Assistance Provided Before and During the Virtual 2020 Annual Meeting

Beginning 15 minutes prior to the start of and during the virtual 2020 Annual Meeting, we will have a support team ready to assist stockholders with any technical difficulties they may have accessing or hearing the virtual meeting. If you encounter any difficulties accessing the virtual meeting during the check-in or meeting time, you should call our support team at:

1-917-262-2373 (U.S. Domestic Toll Free)

1-917-262-2373 (International)

Solicitation

The cost of soliciting proxies will be borne by the Company. In addition to soliciting stockholders by mail and through our employees, we will request that banks and brokers and other persons representing beneficial owners of the shares forward the proxy solicitation material to such beneficial owners and we may reimburse these parties for their reasonable out-of-pocket costs. We may use the services of our officers, directors and others to solicit proxies, personally or by telephone, facsimile or electronic mail, without additional compensation. We have retained Advantage Proxy to assist us in soliciting proxies using the means referred to above. We will pay the fees of Advantage Proxy, which we expect to be approximately $5,500, plus reimbursement of out-of-pocket expenses.

If you need additional copies of this Proxy Statement or the enclosed proxy card, or if you have other questions about the proposals or how to vote your shares or how to attend the virtual meeting, you may contact our proxy solicitor, Advantage Proxy, at (877) 870-8565 (toll free).

Stockholder Proposals

Proposals of stockholders that are intended to be presented at our 2021 Annual Meeting of Stockholders and the proxy materials for such meeting must comply with the requirements of SEC Rule 14a-8 and must be received by our Secretary no later than December 14, 2020 in order to be included in the proxy statement and proxy materials relating to that meeting. Moreover, with respect to any proposal by a stockholder not seeking to have the proposal included in the proxy statement but seeking to have the proposal considered at our next annual meeting, pursuant to our bylaws such stockholder must provide written notice of such proposal so that it is received by our Secretary at our principal executive offices not less than 90 days nor more than 120 days prior to the anniversary of the date of the proxy statement for the prior year’s annual meeting; provided, however, that in the event that no annual meeting was held in the previous year or the date of the annual meeting is more than 30 days before or after the first anniversary of the preceding year’s annual meeting, notice by the stockholder must be received by the Secretary of the corporation not later than the close of business on the later of the 90th day prior to such annual meeting and the 10th day following the day on which public announcement of the date of such meeting is first made by means of a press release reported by the Dow Jones News Service, Associated Press or a comparable national news service or in a document publicly filed by us with the SEC. In addition, stockholders must comply in all respects with the rules and regulations of the SEC then in effect and the requirements of our bylaws.

4

PROPOSAL 1

ELECTION OF DIRECTORS

The Board of Directors currently consists of five members, each with a term expiring at the Annual Meeting. The Nominating and Corporate Governance Committee of the Board has recommended, and the Board has nominated, the five incumbent directors for election at the Annual Meeting. The shares represented by the enclosed proxy will be voted for the election as directors of the five nominees named below to serve until the 2021 Annual Meeting or until their successors have been duly elected and qualified. All of the nominees have indicated to us that they will be available to serve as directors. If any of the nominees becomes unavailable for any reason or if a vacancy should occur before the election (which events are not anticipated), the shares represented by the enclosed proxy may be voted for such other person or persons recommended by the Board as may be determined by the holders of the proxy. There are no family relationships among our executive officers and directors.

Director Nominees

Individuals nominated for election at the Annual Meeting and their ages as of September 30, 2020 are:

Name	Age	Position
Stephen J. Aselage	69	Chairman of the Board
Jason Amello	51	Director
John M. Dunn	68	Director
Michelle Griffin	55	Director
Chris Schelling	44	Director, President and Chief Executive Officer

Biographical information for our director nominees is set forth below:

Stephen J. Aselage has served as Chairman of the Board since the completion of the Merger in September 2017. From October 2015 until the Merger, Mr. Aselage served as the Chairman of Private Acer’s Board of Directors. Most recently he was the Chief Executive Officer of Retrophin, Inc., a Nasdaq-listed, biopharmaceutical company, from November 2014 until his retirement in January 2019, and remains a member of its Board of Directors since October 2012. From May 2014 to November 2014, Mr. Aselage served as the Chief Operations Officer and interim Chief Executive Officer of Retrophin. Prior to joining Retrophin, he held a variety of roles at BioMarin Pharmaceutical Inc., a Nasdaq-listed biotechnology company, as Executive Vice President and Chief Business Officer from December 2009 to September 2012 and Senior Vice President of Global Commercial Development from July 2005 to December 2009. He has also held leadership roles at Cell Therapeutics, Inc., Sangstat Medical Corporation, Advanced Tissue Sciences, Inc. and Genentech, Inc. Mr. Aselage earned a B.S. in biology from the University of Notre Dame. Mr. Aselage currently serves on the Advisory Council for the Department of Science at the University of Notre Dame and also serves on the Board of Directors at BioCryst Pharmaceuticals, Inc. We believe that Mr. Aselage is qualified to serve on our Board of Directors due to his extensive experience in the pharmaceuticals and biotechnology industry, which will enable him to contribute important insights to our Board of Directors on strategic leadership and drug commercialization matters.

Jason Amello has served as a director since the completion of the Merger in September 2017. Since September 2020, Mr. Amello has served as Chief Financial Officer of Saniona AB, a rare disease biopharmaceutical company listed on Nasdaq Stockholm Small Cap. From September 2013 to August 2020, he served as Senior Vice President, Chief Financial Officer and Treasurer of Akebia Therapeutics, Inc., a Nasdaq-listed biopharmaceutical company. From May 2012 to May 2013, Mr. Amello served as Executive Vice President, Chief Financial Officer and Treasurer of ZIOPHARM Oncology, Inc., a Nasdaq-listed biopharmaceutical company. From April 2000 to June 2011, he held various positions at Genzyme Corporation, a then Nasdaq-listed biotechnology company, most recently as Senior Vice President, Corporate Controller, and

5

Chief Accounting Officer. Earlier in his career, Mr. Amello spent 10 years in the business advisory and assurance practice of Deloitte, serving in various roles of increasing responsibility through Senior Manager. He currently serves on the Board of Directors of the New England Baptist Hospital, an orthopedic specialty hospital. Mr. Amello earned a B.A. in accounting from Boston College and is a Certified Public Accountant in the Commonwealth of Massachusetts. We believe that Mr. Amello is qualified to serve on our Board of Directors due to his extensive experience in finance related to managing life sciences companies, which will enable him to contribute important insights to our Board of Directors on financial matters toward the continued growth and expansion of Acer.

John M. Dunn has served as a director since the completion of the Merger in September 2017. From October 2015 until the Merger, Mr. Dunn served as a member of Private Acer’s Board of Directors. From November 2014 to April 2019, he served as General Counsel of Vital Therapies, Inc., a Nasdaq-listed biotherapeutic company. Prior to joining Vital Therapies, Mr. Dunn was a consultant from February 2012 to November 2014, an Executive Vice President of Biogen Idec, Inc., now Biogen Inc., a biotechnology company, from November 2003 to January 2012, where he was the head of that firm’s corporate venture group, and General Counsel of IDEC Pharmaceuticals from 2002 until its merger with Biogen in November 2003. Mr. Dunn has served as a director of Sharp Healthcare, a nonprofit regional health care delivery system, since 2019. Mr. Dunn earned a B.S. in finance and a J.D. from the University of Wyoming. We believe that Mr. Dunn is qualified to serve on our Board of Directors as a result of his deep experience relating to corporate governance and regulatory and financing matters in the pharmaceuticals and biotechnology industry, which will enable him to contribute important strategic insights to our Board of Directors.

Michelle Griffin has served as a director since the completion of the Merger in September 2017. Since April 2013, Ms. Griffin has served as the Principal of Pacific Biotechnology Consulting Group, a firm providing consulting services to biotechnology companies and their Boards of Directors. Prior to her time with Pacific Biotechnology Consulting Group, Ms. Griffin served from January 2011 to March 2013 as Executive Vice President, Operations and Chief Financial Officer of OncoGenex Pharmaceuticals, Inc. Ms. Griffin has served as a member of the Board of Directors and as Chair of the Audit Committee for publicly traded companies Adaptive Biotechnologies Corporation since March 2019 and HTG Molecular Diagnostics, Inc. since August 2018. Ms. Griffin previously served as a member of the Board of Directors and as Chair of the Audit Committee for publicly traded companies PhaseRx, Inc. from 2016 until its acquisition by Roivant Sciences GmbH in 2018, OncoGenex Pharmaceuticals, Inc. from 2008 to 2011, and Sonus Pharmaceuticals, Inc. (subsequently acquired by OncoGenex) from 2004 to 2008. During various periods from 1997 to 2011, she served in the capacity of Chief Financial Officer for Trubion Pharmaceuticals, Inc., Dendreon Corporation and Corixa Corporation. Ms. Griffin earned a B.S. in marketing from George Mason University and an M.B.A. with a specialization in finance and international business from Seattle University. We believe that Ms. Griffin is qualified to serve on our Board of Directors as a result of her extensive operational experience in the biotechnology industry and deep experience in public company financial matters, which will enable her to contribute important insights to our Board of Directors on drug development and financial matters.

Chris Schelling has served as a director and as our President and Chief Executive Officer since the completion of the Merger in September 2017. Mr. Schelling founded Private Acer in December 2013 and served as a director from that time until the Merger. From December 2013 to February 2016, he served as Private Acer’s Chief Operating Officer, and from February 2016 until the Merger, he served as Private Acer’s President and Chief Executive Officer. Prior to founding Private Acer, he served as Executive Director of Strategic Marketing at BioMarin Pharmaceutical Inc., a Nasdaq-listed biotechnology company, from May 2006 to October 2012. Mr. Schelling also founded Censa Pharmaceuticals Inc. in 2015 and currently serves as a director. He has also served as a director at Cascade Prodrug, Inc. since June 2017. He has also held roles at Abgenix, Inc., Cell Therapeutics, Inc., Stanford Research Institute Consulting and Organon. Mr. Schelling earned a B.A. in biology and history from Carroll College. We believe that Mr. Schelling’s role in the founding of Acer, his experience as Acer’s Chief Executive Officer and his experience in the biotechnology industry qualify him to serve on our Board of Directors.

6

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE ELECTION OF EACH THE ABOVE NOMINEES

Board and Committee Meetings

Members of the Board are encouraged to attend the Annual Meeting; however, we do not have a policy regarding director attendance at annual meetings. No directors attended the 2019 annual meeting. During the year ended December 31, 2019, the Board held seven meetings, and each director attended at least 75% of the total number of meetings held by the Board and all committees on which such director served during the period he or she was a director.

Director Independence

The Board has determined that Ms. Griffin and Messrs. Amello, Aselage and Dunn are each an independent director within the meaning of Nasdaq listing standards, which directors constitute a majority of the Board. The Board has determined that each member of the Board’s Audit, Compensation and Nominating and Corporate Governance Committees is independent (or similarly designated) based on the Board’s application of the standards of Nasdaq and the rules and regulations promulgated by the SEC or the Internal Revenue Service, as appropriate for such committee membership.

Committees of the Board of Directors

We currently have a standing Audit Committee, Compensation Committee, and Nominating and Corporate Governance Committee. The Board has adopted written charters for each of the committees, and copies of the charters are available on our website at www.acertx.com. Please note that the information contained on our website is not incorporated by reference in, or considered to be a part of, this proxy statement.

The current members of these committees are as follows:

Director	Audit Committee		Compensation Committee		Nominating and Corporate Governance Committee
Jason Amello		X
Stephen J. Aselage				C		X
John M. Dunn		X				C
Michelle Griffin		C		X

C = Chair

Audit Committee

The Audit Committee of the Board currently consists of Ms. Griffin (chair), and Messrs. Amello and Dunn, each of whom is an independent, non-employee director. The Audit Committee selects, on behalf of our Board, an independent public accounting firm to audit our financial statements, discusses with the independent auditors their independence, reviews and discusses the audited financial statements with the independent auditors and management, recommends to our Board whether the audited financials should be included in our annual reports to be filed with the SEC, and oversees management’s identification, evaluation, and mitigation of major risks to the Company. The Audit Committee operates pursuant to a written charter. During the last fiscal year, the Audit Committee held four meetings.

All of the members of the Audit Committee are non-employee directors who: (1) met the criteria for independence as required by Nasdaq listing standards and as set forth in Rule 10A-3(b)(1) under the Exchange Act; (2) did not participate in preparation of our financial statements during the past three years; and (3) are able

7

to read and understand fundamental financial statements, including a balance sheet, income statement, and cash flow statement. The Board of Directors has determined that Ms. Griffin and Messrs. Amello and Dunn each, individually, qualifies as an “audit committee financial expert” as defined in SEC rules and regulations and also possesses the financial sophistication and requisite experience as required under Nasdaq listing standards.

Compensation Committee

The Compensation Committee of the Board currently consists of Mr. Aselage (chair) and Ms. Griffin, each of whom is an independent director. The Compensation Committee reviews and approves (1) the annual salaries and other compensation of our executive officers and (2) individual stock and stock option grants. The Compensation Committee also provides assistance and recommendations with respect to our compensation policies and practices, and assists with the administration of our compensation plans. In evaluating executive officer compensation, the Compensation Committee considers recommendations from the Chief Executive Officer with respect to compensation of the other executive officers. From time to time and as it determines necessary or desirable, the Compensation Committee may retain the services of an independent compensation consultant to advise on compensation-related matters relating to the executive officers and independent directors. During the last fiscal year, the Compensation Committee held one meeting. In addition, the Compensation Committee engaged in discussions without formally meeting, to build consensus on various matters, with formal action thereafter taken by the Board.

Nominating and Corporate Governance Committee

The Nominating and Corporate Governance Committee of the Board currently consists of Messrs. Dunn (chair) and Aselage, each of whom was determined by the Board to be an independent director. The Nominating and Corporate Governance Committee assists our Board in fulfilling its responsibilities by: identifying and approving individuals qualified to serve as members of our Board, selecting director nominees for our annual meetings of stockholders, evaluating the performance of our Board, and developing and recommending to our Board corporate governance guidelines and oversight procedures with respect to corporate governance and ethical conduct. In identifying and evaluating candidates, the committee takes into consideration the criteria approved by the Board and such other factors as it deems appropriate. We do not have a formal diversity policy, and the committee considers a broad range of factors in evaluating prospective director nominees. These factors may include judgment, skill, diversity, experience with businesses and other organizations of comparable size, the interplay of the candidate’s experience with the experience of other Board members, and the extent to which the candidate would be a desirable addition to the Board and any committees of the Board. The Committee will consider properly submitted stockholder nominations for candidates for the Board. Following verification of the stockholder status of persons proposing candidates, recommendations will be aggregated and considered by the Committee. If any materials are provided by a stockholder in connection with the nomination of a director candidate, such materials will be forwarded to the Committee. During the last fiscal year, the Nominating and Corporate Governance Committee held one meeting. In addition, the Nominating and Corporate Governance Committee engaged in discussions without formally meeting, to build consensus on various matters, with formal action thereafter taken by the Board.

Risk Oversight

A fundamental part of risk management is not only understanding the risks a company faces and what steps management is taking to manage those risks, but also understanding what level of risk is appropriate for each company. Our Board is actively involved in oversight of risks that could affect Acer. The full Board has retained the responsibility for general oversight of risks, but the Audit Committee primarily oversees those risks that may directly or indirectly impact our financial statements. The Board’s role in the risk oversight process includes receiving reports from members of management and the Audit Committee on areas of material risk to Acer, including operational, financial, legal and regulatory, and strategic risks which enable it to better understand our risk identification, management and mitigation strategies.

8

Board Leadership Structure

The Board does not have a policy on whether the same person should serve as both the chief executive officer and chairman of the Board or, if the roles are separate, whether the chairman should be selected from the non-employee directors or should be an employee. The Board believes that it should have the flexibility to make these determinations at any given point in time in the way that it believes best to provide appropriate leadership for the Company at that time. The Board believes that its current leadership structure, with Mr. Aselage serving as a non-employee Chairman of the Board and Mr. Schelling serving as Chief Executive Officer, is in the best interest of stockholders at this time. The current structure ensures a greater role for the independent directors in the oversight of the Company and active participation of the independent directors in setting agendas and establishing priorities and procedures for the work of the Board.

Director Compensation

The following table presents summary information regarding compensation of the non-employee members of our Board of Directors who served during any part of the fiscal year ended December 31, 2019.

Name	Fees Earned or Paid in Cash($)		Option Awards($)(1)(2)		All Other Compensation($)		Total($)
Jason Amello	$	42,500	$	85,342	$	—	$	127,842
Stephen J. Aselage	$	73,750	$	85,342	$	—	$	159,092
Hubert Birner, Ph.D., MBA (3)	$	—	$	—	$	—	$	—
John M. Dunn	$	50,000	$	85,342	$	—	$	135,342
Michelle Griffin	$	55,000	$	85,342	$	—	$	140,342
Luc Marengere, Ph.D. (3)	$	—	$	—	$	—	$	—

(1) Amounts shown in this column represent the aggregate grant date fair value of stock option awards made during 2019, calculated in accordance with Accounting Standards Codification, or ASC, Topic 718. See Note 2 to our consolidated financial statements appearing in our Annual Report on Form 10-K for a discussion of the relevant assumptions used in calculating these amounts.

(2) The aggregate number of shares underlying outstanding option awards as of December 31, 2019 was: Mr. Amello, 15,000 shares; Mr. Aselage, 33,000 shares; Dr. Birner, 0 shares; Mr. Dunn, 28,000 shares; Ms. Griffin, 15,000 shares; and Dr. Marengere, 0 shares.

(3) Drs. Birner and Marengere did not stand for reelection at our 2019 annual meeting of stockholders. Drs. Birner and Marengere were each affiliated with TVM Capital Life Sciences and did not receive compensation for their service on our Board of Directors, which ended on May 17, 2019.

Compensation Arrangements

Independent directors receive compensation for their service on our Board of Directors that consists of cash compensation and equity awards as described below. A director who is also our employee does not receive any additional compensation for services as a member of our Board. We reimburse our directors for travel and lodging expenses in connection with their attendance at Board and committee meetings. Our annual compensation arrangements consist of the following:

Board Member Cash Compensation:

• Annual Board member retainer - $35,000

• Additional non-executive Board Chair retainer - $25,000

Additional Committee Chair Cash Compensation:

• Audit - $15,000

9

• Compensation - $10,000

• Nominating/Governance - $7,500

Additional Committee Member Cash Compensation:

• Audit - $7,500

• Compensation - $5,000

• Nominating/Governance - $3,750

Board Member Equity Compensation:

• Initial stock option award to newly-appointed directors – 9,000 shares, vesting quarterly over a three-year period from the date of grant, with vesting to accelerate immediately prior to a Change in Control (as defined in our 2018 Stock Incentive Plan).

• Annual stock option award – 6,000 shares, vesting on the one-year anniversary from the date of grant, with vesting to accelerate immediately prior to a Change in Control (as defined in our 2018 Stock Incentive Plan).

Communications to the Board of Directors

The Board has adopted the following policy for stockholders who wish to communicate any concern directly with the Board. Stockholders may mail or deliver their communication to our principal executive offices, addressed as follows:

Addressee (*)

c/o Secretary

Acer Therapeutics Inc.

One Gateway Center, Suite 351

300 Washington Street

Newton, MA 02458

*Addressees: Board of Directors; Audit Committee of the Board of Directors; Nominating and Corporate Governance Committee of the Board of Directors; Compensation Committee of the Board of Directors; name of individual director.

Copies of written communications received at such address will be forwarded to the addressee as soon as practicable.

10

AUDIT COMMITTEE REPORT

The Audit Committee of the Board of Directors currently consists of Ms. Griffin and Messrs. Amello and Dunn, all of whom are independent, non-employee directors.

The Audit Committee operates under a written charter adopted by the Board, which is evaluated annually. The Audit Committee selects, evaluates and, where deemed appropriate, replaces the Company’s independent auditors. The Audit Committee also pre-approves all audit services, engagement fees and terms, and all permitted non-audit engagements, except for certain de minimis amounts.

Management is responsible for the Company’s internal controls and the financial reporting process. The Company’s independent auditors are responsible for performing an independent audit of Acer’s consolidated financial statements in accordance with auditing standards generally accepted in the United States of America and issuing a report on Acer’s consolidated financial statements. The Audit Committee’s responsibility is to monitor and oversee these processes.

In this context, the Audit Committee has reviewed the Company’s audited financial statements for fiscal 2019 and has met and held discussions with management and BDO USA, LLP, the Company’s independent auditors for fiscal 2019. Management represented to the Audit Committee that the Company’s consolidated financial statements for fiscal 2019 were prepared in accordance with accounting principles generally accepted in the United States of America, and the Audit Committee discussed the consolidated financial statements with the independent auditors. The Audit Committee also discussed with BDO USA, LLP the matters required to be discussed by Auditing Standard No. 16, Communications with Audit Committees, as adopted by the Public Company Accounting Oversight Board (PCAOB).

BDO USA, LLP also provided to the Audit Committee the written disclosures and the letter required by applicable requirements of the PCAOB regarding the independent auditors’ communications with the Audit Committee concerning independence, and the Audit Committee discussed with BDO USA, LLP the accounting firm’s independence.

Based upon the Audit Committee’s discussion with management and BDO USA, LLP, and the Audit Committee’s review of the representation of management and the report of BDO USA, LLP to the Audit Committee, the Audit Committee recommended to the Board of Directors that the audited consolidated financial statements be included in the Company’s Annual Report on Form 10-K for the fiscal year ended December 31, 2019 filed with the SEC.

Submitted by the Audit Committee of the

Board of Directors of Acer Therapeutics Inc.:

Michelle Griffin, Chair

Jason Amello

John M. Dunn

11

PROPOSAL 2

RATIFICATION OF INDEPENDENT AUDITORS

The Audit Committee has selected BDO USA, LLP (“BDO”) as an independent registered public accounting firm to audit our financial statements for the year ending December 31, 2020, and our Board has directed that management submit the selection of our independent registered public accounting firm for ratification by our stockholders at the Annual Meeting. BDO has served as our independent registered public accounting firm since March 7, 2019 and audited our financial statements for the fiscal year ended December 31, 2019. Previously, Wolf & Company, P.C. (“Wolf”) audited our financial statements for the fiscal years ended December 31, 2017 and 2018. Wolf also served as the independent registered public accounting firm to Private Acer prior to the Merger.

A representative of BDO is expected to be present at the Annual Meeting, will have an opportunity to make a statement if the representative desires but is not expected to do so, and is expected to be available to respond to appropriate questions.

Neither our bylaws nor other governing documents or law require stockholder ratification of the selection of BDO as our independent registered public accounting firm. However, we are submitting the selection of BDO to the stockholders for ratification as a matter of good corporate practice. If our stockholders fail to ratify the selection, our Audit Committee will reconsider whether or not to retain that firm. Even if the selection is ratified, our 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 our stockholders.

Audit Fees

The following table presents (i) the aggregate fees billed to us for the fiscal year ended December 31, 2019 by BDO, who has served as our independent registered public accounting firm since March 7, 2019 and who audited our financial statements for the fiscal year ended December 31, 2019, and (ii) the aggregate fees billed to us for the fiscal year ended December 31, 2018 by Wolf, who served as our independent registered public accounting firm prior to the selection of BDO and who audited our financial statements for the fiscal year ended December 31, 2018.

	Years Ended December 31,
	2019		2018
	BDO		Wolf
Audit fees(1)	$	283,128	$	113,000
Audit-related fees(2)		—		58,000
Tax fees (3)		—		—
All other fees		—		—
Total fees	$	283,128	$	171,000

(1) Audit fees consist of fees billed for services relating to the audit of our annual financial statement and review of our quarterly financial statements, services that are normally provided in connection with statutory and regulatory filings or engagements, comfort letters, reports on an issuer’s internal controls, and review of documents to be filed with the SEC (e.g. periodic filings, registration statements, and company responses to SEC comment letters).

(2) Audit-related fees are related to other assurance and related services that are traditionally performed by an independent accountant such as employee benefit plan audits, due diligence related to mergers and acquisitions, accounting assistance and audits in connection with proposed or consummated acquisitions,

12

attest services that are not required by statute or regulation, and consultations concerning proposed accounting and reporting standards.

(3) Tax fees are for services relating to tax compliance, tax advice and tax planning.

Change in Independent Registered Public Accounting Firm

On March 7, 2019, we engaged BDO as our independent registered public accounting firm to audit our financial statements for the fiscal year ended December 31, 2019, and we dismissed Wolf. The decision to change accountants was approved by the Audit Committee of our Board of Directors. The report of Wolf on our consolidated financial statements for the year ended December 31, 2018 did not contain an adverse opinion or disclaimer of opinion, nor was it qualified or modified as to uncertainty, audit scope, or accounting principles. During the year ended December 31, 2018 and the subsequent interim period through March 7, 2019, there were no: (1) disagreements (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) with Wolf on any matter of accounting principles or practices, financial statement disclosure, or auditing scope or procedures, which disagreement if not resolved to the satisfaction of Wolf would have caused Wolf to make reference thereto in its reports on the consolidated financial statements for such years, or (2) reportable events (as described in Item 304(a)(1)(v) of Regulation S-K).

During the year ended December 31, 2018 and the subsequent interim period through March 7, 2019, neither we nor anyone on our behalf consulted with BDO regarding either (i) the application of accounting principles to a specific transaction, completed or proposed, or the type of audit opinion that might be rendered on our financial statements, and neither a written report nor oral advice was provided to us that BDO concluded was an important factor considered by us in reaching a decision as to any accounting, auditing or financial reporting issue or (ii) any matter that was either the subject of a disagreement (as defined in Item 304(a)(1)(iv) of Regulation S-K and the related instructions) or a reportable event (as described in Item 304(a)(1)(v) of Regulation S-K).

Policy on Audit Committee Pre-Approval and Permissible Non-Audit Services of Independent Auditors

The Board’s policy is to pre-approve all audit and permissible non-audit services provided by the independent auditors. These services may include audit services, audit-related services, tax services and other services. Pre-approval is generally provided for up to one year and any pre-approval is detailed as to the particular service or category of services and is generally subject to a specific budget. The independent auditors and management are required to periodically report to the Board regarding the extent of services provided by the independent auditors in accordance with this pre-approval, and the fees for the services performed to date. The Board may also pre-approve particular services on a case-by-case basis. The Audit Committee pre-approved 100% of any audit-related services, tax services or other services provided by our independent auditors during the last two fiscal years.

THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” THE RATIFICATION OF

THE SELECTION OF BDO USA, LLP AS OUR INDEPENDENT AUDITORS.

13

EXECUTIVE OFFICERS

Our executive officers are elected by the Board of Directors and serve at the discretion of the Board. Our executive officers and their ages as of September 30, 2020 are as follows:

Name	Age	Position
Chris Schelling	44	President, Chief Executive Officer and Director
Donald R. Joseph	66	Chief Legal Officer and Secretary
John R. Klopp	46	Chief Technical Officer
Harry S. Palmin	50	Chief Operating Officer and Chief Financial Officer
Matthew T. Seibt	49	Chief Commercial Officer

Biographical information for our executive officers other than Mr. Schelling is set forth below:

Donald R. Joseph has served as our Chief Legal Officer and Secretary since April 2018. He previously served as an advisor and consultant to biopharmaceutical and global health organizations. He has over twenty years of biopharmaceutical industry experience, including senior management positions in global health non-profit organizations. Mr. Joseph served as Chief Legal Officer and Board Secretary of Humanigen (previously known as KaloBios Pharmaceuticals, Inc.), a publicly listed company, from June 2013 to November 2015. Prior to Humanigen, he was Chief Executive Officer of BIO Ventures for Global Health, or BVGH, from February to November 2012 and Chief Operating Officer from April 2010 to January 2012. He is a former Chairman and Secretary and former member of the BVGH Board of Directors. He previously served as General Counsel, Corporate Secretary, and in other senior management roles at publicly held biopharmaceutical companies, including Abgenix and Renovis. Mr. Joseph has served since August 2017 as lead independent director of Achieve Life Sciences, a publicly traded pharmaceutical company. Before entering the life sciences industry, Mr. Joseph practiced business law for a number of years in major firms, including as an international partner at Baker & McKenzie. He received his J.D. degree from the University of Texas School of Law, with honors.

John R. Klopp has served as our Chief Technical Officer since September 2019. He previously served as our Vice President, Manufacturing from January 2018 to September 2019. Prior to joining Acer, Mr. Klopp served as Senior Director, Manufacturing Management for Ultragenyx Pharmaceutical Inc., a biopharmaceutical company, where he worked from March 2013 to January 2018. Mr. Klopp holds a B.S. degree in chemistry from Pennsylvania State University and an M.S. in chemistry from the University of California, Berkeley.

Harry S. Palmin has served as our Chief Financial Officer since the completion of the Merger in September 2017 and was appointed to the additional position of Chief Operating Officer in September 2018. From December 2013 to February 2016, Mr. Palmin served as the President, Chief Executive Officer and a director of Private Acer, and from February 2016 to September 2017 he served as Private Acer’s acting Chief Financial Officer. Prior to joining Private Acer, he served in a variety of roles at Novelos Therapeutics, Inc., a pharmaceutical company, including as President and director from 1998 to October 2013, Chief Executive Officer from January 2005 to October 2013 and acting Chief Financial Officer from 1998 to September 2005. He has also held roles at Lehman Brothers and Morgan Stanley. Mr. Palmin earned a B.A. in economics from Brandeis University and an M.A. in international economics and finance from the Brandeis University International Business School.

Matthew T. Seibt has served as our Chief Commercial Officer since September 2019. He previously served as our acting Chief Commercial Officer from March 2019 to September 2019 and as our Vice President, Market Access and Reimbursement from April 2018 to March 2019. Prior to joining Acer, Mr. Seibt served as Director, Account Management, Market Access, and Reimbursement at Biogen Inc., a biotechnology company, from December 2014 to April 2018. Mr. Seibt holds a B.A. in Economics and Government from the University of Texas.

14

EXECUTIVE COMPENSATION AND OTHER INFORMATION

Executive Officer Compensation

The following table sets forth certain information concerning compensation earned by or paid to certain persons who we refer to as our “Named Executive Officers” for services provided for the fiscal years ended December 31, 2019 and 2018.

Summary Compensation Table

Name and Principal Position	Year		Salary($)		Bonus($)			Option Awards($)(1)			Stock Awards($)(1)			All Other Compensation ($)		Total($)
Chris Schelling		2019	$	436,000	$	—		$	1,031,211	(2)	$	—		$	—	$	1,467,211
President and Chief Executive Officer		2018	$	400,000	$	150,000	(3)	$	—		$	—		$	—	$	550,000
William T. Andrews, M.D., FACP		2019	$	412,000	$	—		$	462,041	(2)	$	212,400	(4)	$	—	$	1,086,441
Former Chief Medical Officer(5)		2018	$	400,000	$	105,000	(3)	$	—		$	—		$	—	$	505,000
Harry S. Palmin		2019	$	382,400	$	—		$	462,041	(2)	$	—		$	—	$	844,441
Chief Operating Officer and Chief Financial Officer		2018	$	340,000	$	89,250	(3)	$	—		$	—		$	—	$	429,250

(1) Amounts shown in this column represent the aggregate grant date fair value of awards made during the years presented, calculated in accordance with ASC Topic 718. See Note 2 to our consolidated financial statements appearing in our Annual Report on Form 10-K for a discussion of the relevant assumptions used in calculating these amounts.

(2) Option awards were granted (i) on February 1, 2019 to Dr. Andrews and Messrs. Schelling and Palmin, and (ii) on September 18, 2019 to Dr. Andrews and Mr. Palmin, each with an exercise price equal to the closing market price of our common stock on the Nasdaq Capital Market on the date of grant. The options are time-based. The February 1 option grants vest over a four-year period, with 25% of the shares vesting on the one-year anniversary of the grant date and the remaining shares vesting quarterly over the remaining three-year period, assuming continued service. The September 18 option grants vest 50% on January 1, 2021 and 50% on January 1, 2022, assuming continued service. The options have a standard post-service exercise period of 90 days. The options will accelerate and become fully vested immediately prior to a Change in Control (as defined in our 2018 Stock Incentive Plan), but only to the extent that the optionee remains in service immediately prior to such Change in Control.

(3) Represents bonuses earned during 2018 and paid during 2019.

(4) We issued Dr. Andrews a restricted stock unit representing 9,000 shares of common stock on March 1, 2019, which subsequently vested in full on March 1, 2020 and settled on March 2, 2020.

(5) Dr. Andrews resigned effective July 8, 2020.

Narrative Disclosure to Summary Compensation Table

Our Board of Directors reviews compensation annually for all of the executive officers. Compensation awarded to Named Executive Officers in 2019 and 2018 generally consisted of base salary and equity awards for options to purchase shares of our common stock or restricted stock units. In setting executive compensation, our Board retained the services of Radford (which is a part of Aon Hewitt, a business unit of Aon plc) as an independent compensation consultant and considered compensation for comparable positions in the market, the historical compensation levels of the executives, individual performance as compared to its expectations and objectives, the desire to motivate employees to achieve short- and long-term results that are in the best interests

15

of our stockholders, and a long-term commitment to our company. We do not target a specific competitive position or a specific mix of compensation among elements of compensation. Prior to the September 2017 Merger, Private Acer retained the services of Radford as an independent compensation consultant to (i) evaluate Private Acer’s executive compensation program and recommend a course of action for consideration in preparation for becoming a public company and (ii) assess Private Acer’s non-employee director compensation practices against a selection of peer group companies and make a recommendation relating thereto. Subsequent to closing of the Merger in September 2017, our Compensation Committee reviewed the analysis and reports prepared by Radford and provided to Private Acer and implemented certain compensation adjustments for our executives and non-employee directors. In reviewing the reports prepared by Radford for Private Acer, our Compensation Committee considered the independence of Radford pursuant to SEC rules and the corporate governance rules of the Nasdaq Capital Market and concluded that no conflict of interest exists that would prevent Radford from independently advising the Compensation Committee.

Outstanding Equity Awards at Fiscal Year-End

The following table presents information regarding outstanding equity awards at December 31, 2019 for each of the Named Executive Officers.

	Option Awards											Stock Awards
Name	Grant Date		Number of Securities Underlying Unexercised Options (#) Exercisable		Number of Securities Underlying Unexercised Options (#) Unexercisable			Option Exercise Price ($)		Option Expiration Date		Number of shares or units of stock that have not vested (#)			Market value of shares or units of stock that have not vested ($)
Chris Schelling		2/1/19		—		72,500	(1)	$	24.46		2/1/2029		—			—
		10/4/17		23,000		23,000	(1)	$	15.34		10/4/2027		—			—
William T. Andrews, M.D., FACP (2)		9/18/19		—		40,000	(3)	$	3.42		9/18/2029		—			—
		2/1/19		—		27,000	(1)	$	24.46		2/1/2029		—			—
		10/4/17		50,000		50,000	(1)	$	15.34		10/4/2027		—			—
		3/1/19		—		—			—		—		9,000	(4)	$	36,090	(5)
Harry S. Palmin		9/18/19		—		40,000	(3)	$	3.42		9/18/2029		—			—
		2/1/19		—		27,000	(1)	$	24.46		2/1/2029		—			—
		10/4/17		33,800		33,800	(1)	$	15.34		10/4/2027		—			—

(1) These options are time-based and vest over a four-year period, with 25% of the shares vesting on the one-year anniversary of the grant date and the remaining shares vesting quarterly over the remaining three-year period, assuming continued service. The options have a standard post-service exercise period of 90 days. The options will accelerate and become fully vested immediately prior to a Change in Control (as defined in our 2010 Stock Incentive Plan and our 2018 Stock Incentive Plan, as applicable), but only to the extent that the optionee remains in service immediately prior to such Change in Control.

(2) Dr. Andrews resigned effective July 8, 2020.

(3) These options are time-based and 50% vest on January 1, 2021 and 50% on January 1, 2022, assuming continued service. The options have a standard post-service exercise period of 90 days. The options will accelerate and become fully vested immediately prior to a Change in Control (as defined in our 2010 Stock Incentive Plan and our 2018 Stock Incentive Plan, as applicable), but only to the extent that the optionee remains in service immediately prior to such Change in Control.

(4) The restricted stock units vested subsequently in full on March 1, 2020 and settled on March 2, 2020.

(5) The market value of the unvested RSUs was calculated by multiplying the number of units shown in the table by $4.01, the closing price of our common stock on December 31, 2019.

16

Certain Relationships and Related Party Transactions

Transactions with Related Persons

Since January 1, 2019, we have engaged in the following reportable transactions with our directors, executive officers, beneficial holders of more than 5% of our voting securities, and affiliates or their immediate family members:

On July 24, 2020, we entered into a securities purchase agreement for the sale and issuance of an aggregate of 244,998 shares of our common stock, for an aggregate purchase price of $857,493, in a private placement transaction at a price per share of $3.50, which represented a 5.7% premium to the $3.31 closing price of the common stock on that day. The shares were purchased by the following directors, executive officers and employees:

Name	Relationship	Purchase Price		Number of Shares Purchased
Chris Schelling	President, Chief Executive Officer and Director	$	499,999.50		142,857
Stephen J. Aselage	Chairman of the Board of Directors	$	157,500.00		45,000
John M. Dunn	Director	$	74,998.00		21,428
Donald R. Joseph	Chief Legal Officer	$	49,997.50		14,285
Jefferson Davis	Employee	$	74,998.00		21,428

The shares of common stock issued in the private placement constitute “restricted securities” under the federal securities laws and are subject to a minimum six-month holding period. The private placement closed on July 29, 2020.

Securities Authorized for Issuance Under Equity Compensation Plans

The following table sets forth information, as of December 31, 2019, with respect to our compensation plans under which common stock is authorized for issuance. These plans consist of our 2018 Stock Incentive Plan, 2013 Stock Incentive Plan and 2010 Stock Incentive Plan. We believe that the exercise price for all of the options granted under these plans reflect at least 100% of fair market value on the dates of grant for the options at issue.

Equity Compensation Plan Information

Plan Category	Number of Securities to be Issued Upon Exercise of Outstanding Options, Warrants and Rights (A)		Weighted Average Exercise Price of Outstanding Options, Warrants and Rights (B)		Number of Securities Remaining Available for Future Issuance Under Equity Compensation Plans (Excluding Securities Reflected in Column A) (C)
Equity Compensation Plans Approved by Stockholders		1,322,475	$	12.28		162,004
Equity Compensation Plans Not Approved by Stockholders		—		—		—
Total		1,322,475	$	12.28		162,004

17

SECURITY OWNERSHIP OF CERTAIN BENEFICIAL OWNERS AND MANAGEMENT

Beneficial Ownership

The following table sets forth, as of September 30, 2020, the number and percentage of outstanding shares of our common stock beneficially owned by: (a) each person who is known by us to be the beneficial owner of more than 5% of our outstanding shares of common stock; (b) each of our directors and nominees; (c) the Named Executive Officers; and (d) all current directors and executive officers as a group. As of September 30, 2020, there were 11,912,731 shares of common stock issued and outstanding.

Beneficial ownership has been determined in accordance with Rule 13d-3 under the Exchange Act. Under this rule, certain shares may be deemed to be beneficially owned by more than one person (if, for example, persons share the power to vote or the power to dispose of the shares). In addition, shares are deemed to be beneficially owned by a person if the person has the right to acquire shares (for example, upon exercise of an option or warrant) within 60 days of the date as of which the information is provided. In computing the percentage ownership of any person, the number of shares is deemed to include the number of shares beneficially owned by such person by reason of such acquisition rights. As a result, the percentage of outstanding shares of any person as shown in the following table does not necessarily reflect the person’s actual voting power at any particular date.

To our knowledge, except as indicated in the footnotes to this table and pursuant to applicable community property laws, the persons named in the table have sole voting and investment power with respect to all shares of common stock shown as beneficially owned by them.

Beneficial Ownership Table

Name and Address of Beneficial Owner (1)	Number of Shares Owned			Percentage of Class
5% Stockholders (excluding Executive Officers and Directors):
Funds affiliated with TVM Capital Life Science		2,672,309	(2)		22.4	%
Nantahala Capital Management, LLC		990,655	(3)		8.3	%
AIGH Capital Management, LLC		982,446	(4)		8.3	%
Executive Officers and Directors:
Chris Schelling		1,959,075	(5)		16.4	%
William T. Andrews, M.D., FACP (6)		5,858			*
Harry S. Palmin		187,514	(7)		1.6	%
Jason Amello		15,000	(8)		*
Stephen J. Aselage		96,905	(9)		*
John M. Dunn		55,380	(10)		*
Michelle Griffin		15,000	(11)		*
All current directors and executive officers as a group (9 persons)		2,434,920	(12)		19.9	%

* Less than 1%

(1) Unless otherwise indicated in the footnotes, the mailing address of the beneficial owner is c/o Acer Therapeutics Inc., One Gateway Center, Suite 351, 300 Washington Street, Newton, Massachusetts 02458.

(2) This information is based on Amendment No. 1 to Schedule 13D filed with the SEC on August 24, 2018. Consisting of shares of common stock beneficially owned by certain investment funds affiliated with TVM Capital Life Science as follows: (i) 1,697,709 shares of common stock held by TVM Life Science Ventures VII L.P. (“TVM VII LP”); (ii) 725,844 shares of common stock held by TVM Life Science Ventures VI GmbH & Co. KG (“TVM VI German”); and (iii) 248,756 shares of common stock held by TVM Life Science Ventures VI L.P. (“TVM VI Cayman”). With respect to the shares held by TVM VII LP, TVM LSV

18

VII (GP) Ltd. (“TVM VII GP”) is the general partner of TVM VII LP. Luc Marengere, Reshentha Beeby, Gary Leatt, Hubert Birner, Stefan Fischer and Helmut Schühsler are members of the investment committee of TVM VII GP, which has voting and investment power with respect to these shares, and may be deemed to beneficially own such shares. TVM VII GP and Messrs. Birner, Fischer, Schühsler, Marengere and Leatt and Ms. Beeby each disclaim beneficial ownership of the reported securities, other than those shares which the reporting person owns of record. The address of TVM VII LP is 204, Rue Notre-Dame Ouest, Bureau 350, Montreal A8 H2Y 1TE, Canada. With respect to the shares held by TVM VI German, Messrs. Birner, Fischer and Schühsler are members of the investment committee of TVM Life Science Ventures Management VI L.P. (“TVM VI Management”), which is the managing limited partner of TVM VI German with voting and dispositive power over the shares held by TVM VI German, and may be deemed to beneficially own such shares. TVM VI Management and Messrs. Birner, Fischer and Schühsler each disclaim beneficial ownership of the shares held by TVM VI German, other than those shares which the reporting person owns of record. The address of TVM VI German is Ottostrasse 4, 80333 Munich, Germany. With respect to the shares held by TVM VI Cayman, Messrs. Birner, Schühsler and Fisher are members of the investment committee of TVM VI Management, which is the managing limited partner of TVM VI Cayman with voting and dispositive power over the shares held by TVM VI Cayman, and may be deemed to beneficially own such shares. TVM VI Management and Messrs. Birner, Schühsler and Fischer each disclaim beneficial ownership of the shares held by TVM VI Cayman, other than those shares which the reporting persons owns of record. The address of TVM VI Cayman is Ottostrasse 4, 80333 Munich, Germany.

(3) This information is based on a Schedule 13G/A filed with the SEC on February 12, 2020. Pursuant to the Schedule 13G, Nantahala Capital Management, LLC (“Nantahala”) and each of Wilmot B. Harkey and Daniel Mack, as managing members of Nantahala, share voting and investment power with respect to the shares, which are held by funds and separately managed accounts under control of Nantahala. The address for Nantahala and Messrs. Harkey and Mack is 130 Main Street, 2nd Floor, New Canaan, Connecticut 06840.

(4) This information is based on a Schedule 13G/A filed with the SEC on August 6, 2020. Pursuant to the Schedule 13G, AIGH Capital Management, LLC (“AIGH”) and Orin Hirschman, as managing member of AIGH and president of AIGH Investment Partners, LLC, each have sole voting and investment power with respect to the shares which are held directly by the persons named therein. The address for AIGH and Mr. Hirschman is 6006 Berkeley Avenue, Baltimore, Maryland 21209.

(5) Consisting of (i) 1,892,857 shares of common stock; and (ii) 66,218 shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

(6) Dr. Andrews resigned effective July 8, 2020.

(7) Consisting of (i) 125,000 shares of common stock; and (ii) 62,514 shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

(8) Represents shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

(9) Consisting of (i) 63,905 shares of common stock; and (ii) 33,000 shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

(10) Consisting of (i) 27,380 shares of common stock; and (ii) 28,000 shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

(11) Represents shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

(12) Consisting of: (i) 2,123,427 shares of common stock; and (ii) 311,493 shares of common stock underlying stock options exercisable within 60 days of September 30, 2020.

19

Delinquent Section 16(a) Reports

Section 16(a) of the Exchange Act requires our directors and executive officers, and persons who beneficially own more than 10% of a registered class of our equity securities, to file with the SEC initial reports of ownership and reports of changes in ownership. These reporting persons are required by SEC regulations to furnish us with copies of all such reports they file. To our knowledge, based solely on our review of the copies of such reports furnished to us and written representations from certain insiders that no other reports were required, we believe all of the reporting persons complied with all applicable Section 16(a) filing requirements applicable to them with respect to transactions during the fiscal year ended December 31, 2019 except one Form 4 reporting the grant of an employee stock option for each of the following executive officers that was due on September 20, 2019 and was filed on September 23, 2019: Harry S. Palmin, William T. Andrews, Donald R. Joseph, and Matthew T. Seibt; and one Form 4 that was due on September 20, 2019 and filed on September 25, 2019 for John M. Klopp.

HOUSEHOLDING

The SEC has adopted rules that permit companies and intermediaries (e.g., brokers) to satisfy the delivery requirements for proxy statements and annual reports with respect to two or more stockholders sharing the same address by delivering a single proxy statement addressed to those stockholders. This process, which is commonly referred to as “householding,” potentially means extra convenience for stockholders and cost savings for companies.

A number of brokers with account holders who are our stockholders may be “householding” our proxy materials. If householding is in effect, a single proxy statement 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 copy of the proxy statement and annual report, please notify your broker. Stockholders who currently receive multiple copies of the proxy statement and/or annual report at their address and would like to request “householding” of their communications should contact their broker. We will deliver a separate set of proxy materials promptly upon written or oral request from a stockholder. Please direct any such requests to Investor Relations, Acer Therapeutics Inc., One Gateway Center, Suite 351, 300 Washington Street, Newton, Massachusetts 02458, or call Investor Relations at (844) 902-6100.

20

OTHER BUSINESS

The Board knows of no other business to come before the Annual Meeting. However, if any other matters are properly brought before the Annual Meeting, the person named in the accompanying form of proxy or his or their substitutes will vote in their discretion on those matters.

By Order of the Board of Directors

Chris Schelling

President and Chief Executive Officer

October 14, 2020

Newton, Massachusetts

WHETHER OR NOT YOU PLAN TO ATTEND THE VIRTUAL MEETING, PLEASE COMPLETE, SIGN, DATE, AND PROMPTLY RETURN THE ACCOMPANYING PROXY IN THE ENCLOSED ENVELOPE OR USE ONE OF THE VOTING METHODS DESCRIBED IN THE ATTACHED MATERIALS. YOU MAY REVOKE YOUR PROXY AT ANY TIME PRIOR TO THE ANNUAL MEETING. IF YOU DECIDE TO ATTEND THE VIRTUAL MEETING AND WISH TO CHANGE YOUR PROXY VOTE, YOU MAY DO SO AUTOMATICALLY BY VOTING ELECTRONICALLY AT THE MEETING. IF YOUR SHARES ARE HELD OF RECORD BY A BROKER, BANK OR OTHER NOMINEE AND YOU WISH TO ATTEND AND VOTE AT THE MEETING, YOU MUST OBTAIN FROM THE RECORD HOLDER A LEGAL PROXY ISSUED IN YOUR NAME.

THANK YOU FOR YOUR ATTENTION TO THIS MATTER. YOUR PROMPT RESPONSE WILL GREATLY FACILITATE ARRANGEMENTS FOR THE ANNUAL MEETING.

If you need additional copies of this Proxy Statement or the enclosed proxy card, or if you have other questions about the proposals or how to vote your shares, you may contact our proxy solicitor:

ADVANTAGE PROXY

(877) 870-8565 (toll free)

21

YOUR VOTE IS IMPORTANT. PLEASE VOTE TODAY.

Vote by Internet – QUICK ««« EASY

IMMEDIATE – 24 Hours a Day, 7 Days a Week or by Mail

	As a stockholder of Acer Therapeutics Inc., you have the option of voting your shares electronically through the Internet, eliminating the need to return the proxy card. Your electronic vote authorizes the named proxies to vote your shares in the same manner as if you marked, signed, dated and returned your proxy card. Votes submitted electronically over the Internet must be received by 11:59 p.m., Eastern Time, on November 18, 2020.
ACER THERAPEUTICS INC.
		INTERNET/MOBILE —
		https://www.cstproxyvote.com
		Use the Internet to vote your proxy. Have your proxy card available when you access the above website. Follow the prompts to vote your shares.
		Vote at the Meeting — If you plan to attend the virtual online Annual Meeting, you will need your control number to vote electronically at the meeting. To attend: https://www.cstproxy.com/acertx/2020
		MAIL – Mark, sign and date your proxy card and return it in the postage-paid envelope provided.

PLEASE DO NOT RETURN THE PROXY CARD

IF YOU ARE VOTING BY INTERNET.

p FOLD HERE • DO NOT SEPARATE • INSERT IN ENVELOPE PROVIDED p
REVOCABLE PROXY	Please mark your votes like this	☒
THE BOARD OF DIRECTORS RECOMMENDS A VOTE “FOR” EACH OF THE NOMINEES IN PROPOSAL 1 AND “FOR” PROPOSAL 2

PROPOSAL 1 – Election of Directors:

To elect five directors to hold office until the 2021 Annual Meeting of Stockholders.

			WITHHOLD
Election of Directors		FOR	AUTHORITY
01 – Stephen J. Aselage 02 – Jason Amello 03 – John M. Dunn	04 – Michelle Griffin 05 – Chris Schelling	☐	☐

(To withhold authority to vote for any individual nominee, mark the “FOR” box and strike a line through that nominee’s name in the list above)

PROPOSAL 2 – Ratification of Auditors:

To ratify the appointment of BDO USA, LLP as independent auditors for the fiscal year ending December 31, 2020.

☐ FOR ☐ AGAINST ☐ ABSTAIN

THIS PROXY WHEN PROPERLY EXECUTED WILL BE VOTED AS DIRECTED OR, IF NO DIRECTION IS GIVEN, WILL BE VOTED FOR EACH OF THE NOMINEES FOR DIRECTOR IN PROPOSAL 1 AND FOR PROPOSAL 2.

Address Change? Mark Box.	☐
Indicate changes below:

CONTROL NUMBER

Signature                                                                         Signature, if held jointly                                                                     Date                         2020

Please sign exactly as your name(s) appear on Proxy. If held in joint tenancy, all persons should sign. Trustees, administrators, etc., should include title and authority. Corporations should provide full name of corporation and title of authorized officer signing the proxy.

Important Notice Regarding the Availability of Proxy Materials

for the Annual Meeting of Stockholders to be held on November 19, 2020:

Our 2020 Proxy Statement and 2019 Annual Report on Form 10-K are

available at https://www.cstproxy.com/acertx/2020

p FOLD HERE • DO NOT SEPARATE • INSERT IN ENVELOPE PROVIDED p

PROXY

THIS PROXY IS SOLICITED ON BEHALF OF THE BOARD OF DIRECTORS

ACER THERAPEUTICS INC.

ANNUAL MEETING OF STOCKHOLDERS

TO BE HELD ON THURSDAY, NOVEMBER 19, 2020

The undersigned stockholder of Acer Therapeutics Inc. (the “Company”) hereby acknowledges receipt of the Notice of Annual Meeting of Stockholders and appoints each of Harry S. Palmin and Donald R. Joseph, each with full power of substitution, as proxy to vote as specified in this Proxy all the shares of common stock of the Company of the undersigned at the Annual Meeting of Stockholders of the Company to be held on November 19, 2020 at 10:00 a.m. Eastern Time, via the Internet at https://www.cstproxy.com/acertx/2020. Each such proxy or substitute shall have and may exercise all of the powers of said proxy hereunder. The undersigned stockholder hereby revokes any proxy or proxies heretofore executed for such matters.

THIS PROXY, WHEN PROPERLY EXECUTED, WILL BE VOTED IN THE MANNER AS DIRECTED HEREIN BY THE UNDERSIGNED STOCKHOLDER. IF NO DIRECTION IS MADE, THIS PROXY WILL BE VOTED FOR THE ELECTION OF THE NOMINEES IN PROPOSAL 1 AND FOR PROPOSAL 2, AND IN THE DISCRETION OF THE PROXIES AS TO ANY OTHER MATTERS THAT MAY PROPERLY COME BEFORE THE MEETING, INCLUDING ANY ADJOURNMENT OR POSTPONEMENT OF THE MEETING. THE UNDERSIGNED STOCKHOLDER MAY REVOKE THIS PROXY AT ANY TIME BEFORE IT IS VOTED BY DELIVERING TO THE SECRETARY OF THE COMPANY EITHER A WRITTEN REVOCATION OF THE PROXY OR A DULY EXECUTED PROXY BEARING A LATER DATE, OR BY VOTING ELECTRONICALLY AT THE ANNUAL MEETING.

(Continued, and to be marked, dated and signed, on the other side)