Executive Change

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549       FORM 8-K   CURRENT REPORT Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934   Date of Report: August 26, 2025 (Date of earliest event reported)       GT Biopharma, Inc. (Exact name of registrant as specified in its charter)   Delaware (State or other Jurisdiction of Incorporation)   1-40023   94-1620407 (Commission File Number)   (IRS Employer Identification No.)   N/A 1 (Address of Principal Executive Offices and zip code)   (415) 919-4040 (Registrant’s telephone number, including area code)   Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of registrant under any of the following provisions:   ☐ Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)     ☐ Soliciting material pursuant to Rule 14a-12(b) under the Exchange Act (17 CFR 240.14a-12(b))     ☐ Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))     ☐ Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))   Securities registered pursuant to Section 12(b) of the Act:   Title of each Class   Trading Symbol(s)   Name of each Exchange on which registered Common stock, $0.001 par value   GTBP   The Nasdaq Stock Market LLC   Indicate by check mark whether the registrant is an emerging growth company as defined in Rule 405 of the Securities Act of 1933 (§230.405 of this chapter) or Rule 12b-2 of the Securities Exchange Act of 1934 (§240.12b-2 of this chapter).   Emerging growth company ☐   If an emerging growth company, indicate by check mark if the registrant has elected not to use the extended transition period for complying with any new or revised financial accounting standards provided pursuant to Section 13(a) of the Exchange Act. ☐     1 Effective as of July 1, 2024, the Company became a fully remote company. We do not maintain a principal executive office. For purposes of compliance with applicable requirements of the Securities Act of 1933, as amended, and the Securities Exchange Act of 1934, as amended, any stockholder communication required to be sent to the Company’s principal executive offices may be directed to 505 Montgomery Street , 10th Floor , San Francisco , California 94111 , or by email to auditcommittee@gtbiopharma.com.             Item 5.02 Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers.   Amendment No. 3 to the Employment Agreement with Michael Breen   On August 26, 2025, GT Biopharma, Inc. (the “Company”) entered into Amendment No. 3 (“Amendment No. 3”), effective as of April 29, 2025 (the “Effective Date”), to that certain employment agreement, dated as of November 8, 2021 (as previously amended, the “Employment Agreement”), by and between the Company and Michael Breen, the Company’s Executive Chairman and Chief Executive Officer. Pursuant to Amendment No. 3, the Board of Directors of the Company renewed Mr. Breen’s position as Chief Executive Officer for a period of two years from the Effective Date. Upon expiration of the term, Mr. Breen’s employment shall automatically renew for additional two-year periods unless either party gives at least ninety days’ written notice of non-renewal.   The foregoing description of Amendment No. 3 does not purport to be complete and is qualified in its entirety by reference to Amendment No. 3, which is attached hereto as Exhibit 10.1 and is incorporated herein by reference.   Item 9.01 Financial Statements and Exhibits.   (d) Exhibits.   Exhibit Number   Description 10.1   Amendment No. 3 to the Employment Agreement, dated August 26, 2025, by and between GT Biopharma, Inc. and Michael Breen       104   Cover Page Interactive Data File, formatted in Inline XBRL         SIGNATURES   Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.     GT BIOPHARMA, INC.     Date: August 29, 2025 By: /s/ Alan Urban     Alan Urban     Chief Financial Officer