08:27 AM EDT, 10/13/2025 (MT Newswires) -- Arcus Biosciences ( RCUS ) said Monday a phase 2 study on various combinations of domvanalimab plus zimberelimab with chemotherapy achieved a 26.7-month median overall survival in patients with advanced stomach and esophageal cancer, including tumors not removable by surgery, with a 50% two-year survival rate.

The study, conducted in partnership with Gilead Sciences ( GILD ) , also achieved progression-free survival of 12.9 months and confirmed response rate of 59%, with benefit seen across PD-L1 groups, Arcus said.

Safety was broadly in line with anti-PD-1 plus chemotherapy, with no unexpected risks reported, the company added.

Arcus said the results support its ongoing phase 3 Star-221 study testing the same regimen in the same setting, it said.

Shares of the company were up over 9% in recent Monday premarket activity.