Arcus Biosciences and partner Gilead reported a Phase 3 failure for their anti‑TIGIT antibody domvanalimab in upper gastrointestinal cancers, prompting an immediate halt to the program and a strategic R&D reset at Arcus. Company statements and regulatory filings show the independent data monitoring committee recommended stopping the trial for futility. Following the futility finding Arcus said it will abandon several domvanalimab‑related studies and refocus resources across its pipeline; Gilead and Arcus will reassess broader TIGIT development plans. The setback adds to a series of high-profile clinical disappointments for TIGIT as a cancer immunotherapy target and will influence investor sentiment and partner prioritization for similar checkpoint programs. Clinical context: TIGIT is an immune checkpoint receptor; its inhibition had been pursued to enhance anti‑tumor T cell activity but has shown mixed translation from early signals to randomized outcomes.