GT Biopharma, Inc., a clinical stage biopharmaceutical company, focuses on the development and commercialization of immuno-oncology products based on its proprietary Tri-specific Killer Engager (TriKE) fusion protein immune cell engager technology platform. It develops GTB-3550, a single-chain tri-specific recombinant fusion protein conjugate that is in Phase I clinical trial for the treatment of myelodysplastic syndromes, refractory/relapsed acute myeloid leukemia or advanced systemic mastocytosis, and CD33+ malignancies. The company is developing GTB-3650, which is in preclinical studies that target CD33 on the surface of myeloid leukemias; and GTB-5550 that is in preclinical studies for treating patients with B7-H3 positive solid tumors. GT Biopharma, Inc. has a co-development partnership agreement with Altor BioScience Corporation for the clinical development of a 161533 (GTB-3550) TriKE fusion protein for cancer therapies; and a license agreement with the Regents of the University of Minnesota to develop and commercialize cancer therapies using TriKE technology. The company was formerly known as OXIS International, Inc. and changed its name to GT Biopharma, Inc. in July 2017. GT Biopharma, Inc. was incorporated in 1965 and is based in Brisbane, California.