Arcus Biosciences, Inc. (the “Company”) announced the discontinuation of the Phase 3 STAR-221 study

On December 12, 2025, Arcus Biosciences, Inc. (the "Company") reported the discontinuation of the Phase 3 STAR-221 study due to futility. STAR-221 evaluated the anti-TIGIT antibody domvanalimab plus anti-PD-1 antibody zimberelimab and chemotherapy versus nivolumab plus chemotherapy as a first-line treatment for advanced gastric and esophageal cancers.

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The decision is based on the recommendation from the Independent Data Monitoring Committee following its review of data from an event-driven, pre-specified interim analysis of overall survival ("OS"). At the interim analysis, the domvanalimab-based combination did not improve OS relative to nivolumab plus chemotherapy. The safety profile for the domvanalimab-based combination was similar to that of nivolumab plus chemotherapy, and there were no new safety findings identified.

The STAR-221 and the Phase 2 EDGE-Gastric studies will be discontinued, and the Company and Gilead Sciences, Inc. are communicating with investigators to determine appropriate next steps for patients in the study, in addition to conducting a detailed analysis to better understand these results.

Based on existing cash, cash equivalents and marketable securities, the Company expects to be able to fund its planned operations until at least the second half of 2028. Moving forward, the Company’s R&D investment and resources will focus on casdatifan, a potential best-in-class HIF-2a inhibitor, and its emerging small molecule inflammation and autoimmune programs, including an MRGPRX2 inhibitor that is expected to enter the clinic in 2026.

(Press release, Arcus Biosciences, DEC 12, 2025, View Source [SID1234661400])