Company Update

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: (Date of earliest event reported) December 4, 2023       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.)   8000 Marina Blvd. , Suite 100 Brisbane , CA 94005 (Address of Principal Executive Offices and zip code)   (800) 304-9888 (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 under the Exchange Act (17 CFR 240.14a-12)     ☐ 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. ☐             Item 8.01. Other Events.   On December 4, 2023, GT Biopharma, Inc. issued a press release announcing the submission of an Investigational New Drug (IND) application with the US Food and Drug Administration (FDA) for the development of GTB-3650, a 2nd generation nanobody TriKE® for the treatment of patients with CD33+ leukemia.   A copy of the press release is attached hereto as Exhibit 99.1 and is incorporated herein by reference.   Item 9.01 Financial Statements and Exhibits.   (d) Exhibits.   Exhibit Number   Description 99.1   Press Release issued December 4, 2023 entitled “GT Biopharma Announces IND Submission for GTB-3650 for Treatment of CD33+ Leukemia.” 104   Cover Page Interactive Data File (embedded as Inline XBRL document).         SIGNATURE   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: December 4, 2023 By: /s/ Manu Ohri     Manu Ohri     Chief Financial Officer