Obsidian Therapeutics is a clinical-stage biopharmaceutical company developing engineered tumor infiltrating lymphocyte (TIL) cell therapies for solid tumors. The company's lead product candidate is amsoki-cel, an autologous TIL therapy engineered to express membrane-bound IL15, which is regulated by an oral small-molecule drug to control cancer-fighting cell activity. Amsoki-cel is designed for outpatient administration without requiring high-dose IL2 injections. Obsidian is currently evaluating amsoki-cel in a Phase 2 clinical trial for advanced melanoma and a Phase 1 clinical trial for non-small cell lung cancer. The therapy is built on Obsidian's cytoDRiVE platform, which enables regulatable protein expression across cell and gene therapies. Obsidian is pre-revenue and outsources all therapy manufacturing to contract development and manufacturing organizations. The company plans to retain commercial rights to amsoki-cel in the U.S. to sell directly to oncologists and cancer centers, while pursuing partnerships to apply its cytoDRiVE platform outside of core TIL programs.