Arcus Biosciences and partner Gilead halted a Phase III trial of anti‑TIGIT antibody domvanalimab after an independent data monitoring committee flagged futility in first‑line gastric and esophageal cancers. The interim analysis showed the domvanalimab regimen failed to improve overall survival versus the Opdivo plus chemotherapy control, prompting cessation of the Star‑221 program. Arcus said it will shift resources toward casdatifan, an HIF‑2α inhibitor that has shown single‑agent activity in late‑line clear‑cell renal carcinoma and remains in ongoing development. Investors reacted immediately, and the company signaled re‑prioritization of its pipeline while winding down the TIGIT program.