Aptevo Therapeutics Inc. Aptevo Therapeutics Inc is a clinical-stage research and development biotechnology company focused on developing novel immunotherapeutic candidates for the treatment of different forms of cancer. Its clinical candidates are; ALG.APV-527, which targets co-stimulatory receptors and tumor antigens, and CD3xCD123, which is being developed as a potential treatment of frontline acute myelogenous leukemia. The company's preclinical candidates, APVO711, APVO0442, and APVO603, are being developed using the ADAPTIR modular protein technology platform. The company's versatile and robust ADAPTIR and ADAPTIR-FLEX platforms are designed to generate monospecific, bispecific, and multi-specific antibody candidates that are capable of enhancing the human immune system against cancer cells.