Abatacept for Crohn's Disease and Ulcerative Colitis

BACKGROUND & AIMS: The efficacy of abatacept, a selective costimulation modulator, in Crohn's disease (CD) and ulcerative colitis (UC) is unknown. METHODS: Four placebo-controlled trials evaluated the efficacy and safety of abatacept as induction (IP) and maintenance (MP) therapy in adults with active, moderate-to-severe CD (CD-IP; CD-MP) and UC (UC-IP1; UC-MP). In CD-IP and UC-IP1, 451 patients with CD and 490 patients with UC were randomized to abatacept 30, 10, or 3 mg/kg (according to body weight) or placebo, and dosed at weeks 0, 2, 4, and 8. In MP, 90 patients with CD and 131 patients with UC who responded to abatacept at week 12 in the induction trials were randomized to abatacept 10 mg/kg or placebo every 4 weeks through week 52. RESULTS: In CD-IP, 17.2%, 10.2%, and 15.5% of patients receiving abatacept 30, 10, and 3 mg/kg achieved a clinical response at weeks 8 and 12, vs 14.4% receiving placebo (P = .611, P = .311, and P = .812, respectively). In UC-IP1, 21.4%, 19.0%, and 20.3% of patients receiving abatacept 30, 10, and 3 mg/kg achieved a clinical response at week 12, vs 29.5% receiving placebo (P = .124, P = .043, and P = .158, respectively). In CD-MP, 23.8% vs 11.1% of abatacept vs placebo patients were in remission at week 52. In UC-MP, 12.5% vs 14.1% of patients receiving abatacept vs placebo were in remission at week 52. Safety generally was comparable between groups. CONCLUSIONS: The studies showed that abatacept is not efficacious for the treatment of moderate-to-severe CD or UC.