SELLAS Life Sciences Group, Inc., a late-stage biopharmaceutical company, focuses on the development of novel cancer immunotherapies for various cancer indications in the United States. Its lead product candidate is galinpepimut-S (GPS), a cancer immunotherapeutic agent that targets Wilms tumor 1, which is in Phase III clinical trials for the treatment of acute myeloid leukemia; and in Phase 1/2 clinical trials for the treatment for ovarian cancer. The company also develops nelipepimut-S, a cancer immunotherapy that targets human epidermal growth factor receptor 2, which is in Phase 2b clinical trials for the treatment of early-stage breast cancer. It has a strategic collaboration with Merck & Co., Inc. to evaluate GPS as it is administered in combination with PD1 blocker pembrolizumab in a Phase 1/2 clinical trial enrolling patients in up to five cancer indications, including hematologic malignancies and solid tumors. The company was founded in 2012 and is headquartered in New York, New York.