Arcus Biosciences announced a voluntary stop to its Phase 3 Star-221 trial of the anti‑TIGIT antibody domvanalimab in combination with anti‑PD‑1 therapy and chemotherapy after an independent data monitoring committee concluded the regimen will not improve overall survival in first-line gastric and esophageal cancers. Arcus framed the move as a strategic pivot and will discontinue the domvanalimab program in that indication. The company said it will redirect resources to other pipeline assets, including casdatifan, a HIF‑2α inhibitor showing activity in clear-cell renal cell carcinoma. The decision follows a string of high-profile TIGIT program setbacks across the industry and underscores growing challenges for TIGIT as an immuno‑oncology target. Arcus said ongoing development will focus on indications and molecules where single-agent or alternative combination activity appears more promising.