Aptevo Therapeutics Inc., a clinical-stage research and development biotechnology company, focuses on developing immunotherapeutic candidates for the treatment of various forms of cancer in the United States. It develops its products using ADAPTIR and ADAPTIR-FLEX platforms to generate monospecific, bispecific, and multi-specific antibody candidates capable of enhancing the human immune system against cancer cells. The company's lead clinical blood cancer candidate is APVO436 that is in Phase 1b/2 clinical trial for acute myelogenous leukemia. It is also developing ALG.APV-527, a novel investigational bispecific ADAPTIR candidate that is in Phase 1 clinical trial for NSCLC, head and neck, colorectal, pancreatic, breast, and other solid tumors; APVO603, a preclinical dual agonist bispecific ADAPTIR candidate for multiple solid tumors; APVO442, a novel bispecific candidate based on the ADAPTIR-FLEX platform technology for multiple solid tumors; and APVO711, a preclinical dual mechanism bispecific ADAPTIR candidate for prostate cancer. The company has a collaboration and option agreement with Alligator Bioscience AB to develop ALG.APV-527. Aptevo Therapeutics Inc. was incorporated in 2016 and is headquartered in Seattle, Washington.