Efficacy and Safety of Infliximab in Intestinal Behçet's Disease: A Multicenter, Phase 3 Study (BEGIN).

Background/Aims: To date, there is no prospective study that specifically investigated the efficacy of infliximab in intestinal Behçet's disease (BD). This study evaluated the efficacy of infliximab in patients with moderate-to-severe active intestinal BD that are refractory to conventional therapies. Methods: This phase 3, interventional, open-label, single-arm study evaluated clinical outcomes of infliximab treatment in patients with moderate-to-severe intestinal BD. The coprimary endpoints were clinical response, decrease in disease activity index for intestinal BD (DAIBD) score ≥20 from weeks 0 to 8 for the induction therapy and week 32 for the maintenance therapy. Results: A total of 33 patients entered the induction therapy and were treated with infliximab 5 mg/kg intravenously at weeks 0, 2, and 6. The mean DAIBD score changed from 90.8±40.1 at week 0 to 40.3±36.4 at week 8, with a significant mean change of 50.5±36.4 (95% confidence interval, 37.5 to 63.4; p<0.001). Thirty-one (93.9%) continued to receive 5 mg/kg infliximab every 8 weeks during the maintenance therapy. The mean change in the DAIBD score after the maintenance therapy was statistically significant (61.5±38.5; 95% confidence interval, 46.0 to 77.1; p<0.001, from weeks 0 to 32). The proportion of patients who maintained a clinical response was 92.3% at week 32. No severe adverse reactions occurred during the induction and maintenance therapies. Conclusions: This study provided evidence that infliximab 5 mg/kg induction and maintenance therapies are efficacious and well-tolerated in patients with moderate-to-severe active intestinal BD. (ClinicalTrials.gov identifier: NCT02505568).