Moleculin Biotech, Inc.

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 14A

Proxy Statement Pursuant to Section 14(a) of

the Securities Exchange Act of 1934 (Amendment No. )

Filed by the Registrant ☒

Filed by a Party other than the Registrant ☐

Check the appropriate box:

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):

Moleculin Biotech, Inc.

5300 Memorial Drive, Suite 950

Houston, TX 77007

(713) 300-5160

To the Stockholders of Moleculin Biotech, Inc.:

You are cordially invited to attend the Annual Meeting of Stockholders of Moleculin Biotech, Inc. on October 9, 2026. The Annual Meeting will begin at 10:00 a.m. local time at the corporate offices of Moleculin Biotech, Inc., 5300 Memorial Drive, Suite 950, Houston, TX 77007.

In accordance with the Securities and Exchange Commission’s “notice and access” model, we are providing our Notice of Annual Meeting of Shareholders, Proxy Statement, Annual Report on Form 10-K and Amendment No. 1 to our Annual Report on Form 10-K/A for the year ended December 31, 2025, to you online with paper copies available, free of charge, upon request. On or about August 24, 2026, we will begin mailing a Notice of Internet Availability of Proxy Materials detailing how to access the proxy materials electronically and how to submit your proxy via the Internet. The Notice of Internet Availability of Proxy Materials also provides instructions on how to request and obtain paper copies of the proxy materials and proxy card or voting instruction form, as applicable. The Notice of Internet Availability of Proxy Materials is not a proxy card and cannot be used to vote your shares. We believe this process provides our shareholders with a convenient way to access the proxy materials and submit their proxies online, while allowing us to reduce our environmental impact as well as the costs of printing and distribution.

Shareholders of record at the close of business on August 19, 2026 are entitled to vote on the matters presented at the Annual Meeting.

We intend to hold our Annual Meeting in person and we look forward to seeing you on October 9, 2026. We encourage you to attend the Annual Meeting, but if you are unable to attend, it is important that you vote in advance via the Internet, or by signing, dating and returning the proxy card. 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 Annual Meeting.

Very truly yours,

MOLECULIN BIOTECH, INC.

Moleculin Biotech, Inc.

5300 Memorial Drive, Suite 950

Houston, TX 77007

(713) 300-5160

NOTICE OF ANNUAL MEETING OF STOCKHOLDERS

To Be Held October 9, 2026

TO THE STOCKHOLDERS OF MOLECULIN BIOTECH, INC.:

NOTICE IS HEREBY GIVEN that the 2026 Annual Meeting of Stockholders of Moleculin Biotech, Inc. (the “Company”) will be held at the corporate offices at 5300 Memorial Drive, Suite 950, Houston, TX 77007, on October 9, 2026, at 10:00 a.m., local time, for the following purposes, as described in the accompanying Proxy Statement:

The Board of Directors (the “Board”) is not aware of any other business that will be presented for consideration at the Annual Meeting. If any other matters should be properly presented at the Annual Meeting or any adjournments or postponements of the Annual 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.

Only stockholders of record of the Company at the close of business on August 19, 2026, are entitled to notice of and to vote at the Annual Meeting or any adjournment or postponement thereof. A complete list of these stockholders will be open for the examination of any stockholder at the Company’s principal executive offices located at 5300 Memorial Drive, Suite 950, Houston, TX 77007 for a period of ten days prior to the Annual Meeting. The list will also be available for the examination of any stockholder of record present at the Annual Meeting. The Annual Meeting may be adjourned or postponed from time to time without notice other than by announcement at the meeting.

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