As filed with the Securities and Exchange Commission on June 18, 2024 Registration No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM S-1 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 GT BIOPHARMA, INC. (Exact name of registrant as specified in its charter) incorporation or organization Classification Code Number) Identification Number) Delaware 2834 94-1620407 State or other jurisdiction (Primary Standard Industrial (I.R.S. Employer 8000 Marina Blvd., Suite 100 ...