Accro Bio has dosed its first patient in a Phase 2b study of AC-101 (a selective RIPK2 inhibitor) to treat moderate-to-severe ulcerative colitis. The study is a multi-centre, double-blind, trial with two AC-101 cohorts against one placebo-controlled. The primary endpoint is clinical remission at week 12; with exploratory endpoints of histological remission, and maintenance of histological and clinical remission over long-term treatment.