GT Biopharma, Inc., a clinical stage biopharmaceutical company, engages in the development and commercialization of immuno-oncology products based on its Tri-specific Killer Engager (TriKE) and Tetra-specific Killer Engager (Dual Targeting TriKE) platforms. It develops GTB-3650, which is in phase 1 trials that target CD33 on the surface of myeloid leukemias and an agonistic camelid; GTB-5550, that is in phase 1 dose escalation basket trial that targets B7-H3 on the surface of advanced solid tumors;and GTB-7550, a pre-clinical stage product candidate in development for the treatment of lupus and other autoimmune disorders. 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 San Francisco, California.