Moleculin Biotech, Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, DC 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of the

Securities Exchange Act of 1934 (Amendment No. )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

☐ 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 §240.14a-12

Moleculin Biotech, 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 paid previously with preliminary materials.

☐ Fee computed on table in exhibit required by Item 25(b) per Exchange Act Rules 14a6(i)(1) and 0-11

Moleculin Biotech, Inc.

March 9, 2026

Dear Fellow Stockholder:

On behalf of the Board of Directors (the “Board”) and management of Moleculin Biotech, Inc. (the “Company”), you are cordially invited to attend the Special Meeting of Stockholders of the Company to be held on April 15, 2026 at 10:00 a.m. local time at the corporate offices of Moleculin Biotech, Inc., 5300 Memorial Drive, Suite 950, Houston, TX 77007 (the “Special Meeting”).

The attached Notice of the Special Meeting (the “Notice”) and proxy statement (“Proxy Statement”) describe in greater detail all of the formal business that will be transacted at the Special Meeting. Directors and officers of the Company will be available at the Special Meeting to respond to any questions that you may have regarding the business to be transacted.

The Company’s Board has determined that each of the proposals that will be presented to the stockholders for their consideration at the Special Meeting are in the best interests of the Company and its stockholders, and unanimously recommends and urges you to vote“FOR”** the proposals set forth in this Proxy Statement.** If any other business is properly presented at the Special Meeting, the proxies will be voted in accordance with the recommendations of the Company’s Board.

We encourage you to attend the Special Meeting in person, but if you are unable to attend, it is important that you vote in advance via the Internet, by telephone, or sign, date and return the enclosed proxy card in the enclosed postage-paid envelope. Your cooperation is appreciated since one-third of the common stock must be represented, either in person or by proxy, to constitute a quorum for the transaction of business at the Special Meeting.

On behalf of the Board and all of the employees of the Company, we thank you for your continued support.

Very truly yours,

MOLECULIN BIOTECH, INC.

Important Notice Regarding the Availability of Proxy Materials

for the Special Meeting to be Held on April 15, 2026:

Electronic Copies of the Proxy Statement are available at

https://materials.proxyvote.com/60855D

Moleculin Biotech, Inc.

NOTICE OF SPECIAL MEETING OF STOCKHOLDERS TO BE HELD APRIL 15, 2026

NOTICE IS HEREBY GIVENthat a Special Meeting of Stockholders (the “Special Meeting”) of Moleculin Biotech, Inc. (the “Company”) will be at the corporate offices at 5300 Memorial Drive, Suite 950, Houston, TX 77007, on April 15, 2026 at 10:00 a.m., local time, for the following purposes:

1.**Proposal 1.**For purposes of complying with Nasdaq Listing Rule 5635(d), to approve the issuance of up to 6,367,956 shares of Company common stock upon the exercise of certain warrants issued on February 20, 2026 in a private placement (the “Nasdaq Proposal”).

2.**Proposal 2.**To approve an amendment to the Company’s Amended and Restated Certificate of Incorporation, as amended, to change the Company’s name from Moleculin Biotech, Inc. to Moleculin Inc. (the “Name Change Proposal”).

3.**Proposal 3.**To approve an adjournment of the Special Meeting, if necessary, to solicit additional proxies if there are not sufficient votes in favor of the Nasdaq Proposal or the Name Change Proposal (the “Adjournment Proposal”).

Please refer to the proxy statement for the Special Meeting (the “Proxy Statement”) for detailed information on the Nasdaq Proposal, Name Change Proposal and Adjournment Proposal.

The Board of Directors (the “Board”) is not aware of any other business that will be presented for consideration at the Special Meeting. If any other matters should be properly presented at the Special Meeting or any adjournments or postponements of the Special Meeting for action by stockholders, the persons named in the form of proxy will vote the proxy in accordance with their best judgment on that matter.

The Board recommends that you vote “FOR” the Nasdaq Proposal, “FOR” the Name Change Proposal, and “FOR” the Adjournment Proposal.

Only stockholders of record as of the close of business on February 20, 2026 are entitled to receive notice of, to attend and to vote at the Special Meeting. If you are a beneficial owner as of that date, you will receive communications from your broker, bank or other nominee about the Special Meeting and how to direct the vote of your shares, and you are welcome to attend the Special Meeting in person, all as described in more detail in the attached Proxy Statement. The Special Meeting may be adjourned or postponed from time to time without notice other than by announcement at the meeting.

Important Notice Regarding the Availability of Proxy Materials for the Special Meeting to Be Held on April 15, 2026. The Proxy Statement and form of Proxy are available on the Internet at https://materials.proxyvote.com/60855D and on our corporate website at www.moleculin.com under “Investors—SEC Filings.”

WHETHER OR NOT YOU PLAN TO ATTEND THE MEETING, PLEASE SIGN AND DATE THE ENCLOSED PROXY AND RETURN IT IN THE ENVELOPE PROVIDED.