SELLAS Life Sciences Group, Inc. operates as a late-stage biopharmaceutical entity, dedicated to advancing novel cancer immunotherapies for various cancer indications across the United States. Its primary investigational product, galinpepimut-S (GPS), is a cancer immunotherapeutic agent engineered to target Wilms tumor 1. GPS is currently in Phase III clinical trials for acute myeloid leukemia and Phase 1/2 studies for ovarian cancer. Additionally, the company is progressing nelipepimut-S, an immunotherapy aimed at human epidermal growth factor receptor 2, which is undergoing Phase 2b clinical evaluation for early-stage breast cancer. A strategic collaboration with Merck & Co., Inc. is underway to assess GPS in combination with the PD1 blocker pembrolizumab, specifically within a Phase 1/2 clinical trial encompassing up to five distinct cancer indications, including both hematologic malignancies and solid tumors. Founded in 2012, SELLAS maintains its corporate headquarters in New York, New York.