Gilead and Arcus Announce Anti-TIGIT Domvanalimab Plus Zimberelimab and Chemotherapy Exceeded One Year of Median Progression-Free Survival as a First-Line Treatment for Upper GI Cancers

– Data Support the Ongoing Phase 3 STAR-221 Study of Domvanalimab Plus Zimberelimab and Chemotherapy, Potentially the First Anti-TIGIT Combination to Market for These Cancers –

– Results will be Presented Today During an Oral Session at the ASCO Annual Meeting –

FOSTER CITY, Calif. & HAYWARD, Calif.--(BUSINESS WIRE)-- Gilead Sciences, Inc. (Nasdaq: GILD) and Arcus Biosciences, Inc. (NYSE: RCUS) today announced longer-term efficacy and safety results from Arm A1 of the Phase 2 EDGE-Gastric study. These updated data show consistent objective response rate (ORR) and provide mature progression-free survival (PFS) in patients with locally advanced unresectable or metastatic gastric, gastroesophageal junction or esophageal adenocarcinoma (upper GI cancers). The ongoing, multi-arm, global Phase 2 EDGE-Gastric study is evaluating the safety and efficacy of various combinations of the Fc-silent anti-TIGIT antibody domvanalimab plus the anti-PD-1 monoclonal antibody zimberelimab and chemotherapy in this patient population. These results will be presented today during the American Society of Clinical Oncology (ASCO) Plenary Series: Rapid Abstract Updates session by Yelena Y. Janjigian, M.D., Chief, Gastrointestinal Oncology, Memorial Sloan Kettering Cancer Center, and a principal investigator for the EDGE-Gastric study (Abstract 433248).

“I am encouraged to see that patients treated with domvanalimab plus zimberelimab and chemotherapy had a median progression-free survival beyond one year, which exceeds the historical benchmarks for anti-PD-1 plus chemotherapy alone,” said Dr. Janjigian. “Notably, nearly 60% of patients in the EDGE-Gastric study achieved progression-free survival at 12 months. These promising results reinforce our confidence in the ongoing Phase 3 STAR-221 study, which evaluates the same regimen in the same patient population and has the potential to address a high unmet need for people with these cancers.”

At data cutoff (DCO, March 12, 2024), safety and efficacy were evaluated in all patients enrolled and treated (n=41). With a median time on treatment of 49.4 weeks (range: 0.4 - 79.4 weeks), the domvanalimab plus zimberelimab and chemotherapy regimen demonstrated sustained improvement across efficacy measures, including in those patients who have low PD-L1 expression.