Aptevo Therapeutics Inc. is a clinical-stage biotechnology company primarily focused on pioneering immunotherapeutic agents for a variety of cancer treatments across the United States. Its foremost investigational drug, APVO436, is a bispecific antibody crafted to engage T-cells, which is currently undergoing a Phase 1b clinical study for acute myeloid leukemia and myelodysplastic syndromes. Beyond its lead asset, Aptevo's research pipeline encompasses several preclinical compounds. These include ALG.APV-527, an experimental bispecific ADAPTIR molecule designed to target both 4-1BB (CD137) and 5T4, a tumor-specific antigen prevalent in numerous cancer types. Another promising candidate is APVO603, a dual agonist bispecific antibody that targets both 4-1BB and OX40. The company is also advancing APVO442, a bispecific agent leveraging its ADAPTIR-FLEX platform technology to improve the precise delivery of drugs to prostate-specific membrane antigen (PSMA)-positive tumors for the treatment of prostate cancer. To further its development efforts for ALG.APV-527, Aptevo maintains a collaborative partnership and option agreement with Alligator Bioscience AB. Founded in 2016, Aptevo Therapeutics Inc. operates from its headquarters located in Seattle, Washington.