Efficacy and Safety of Oral Budesonide in Patients with Active Crohn's Disease in Japan: A Multicenter, Double-Blind, Randomized, Parallel-Group Phase 3 Study

BACKGROUND: US and European guidelines recommend budesonide for the treatment of mild-to-moderate active ileocolic Crohn's disease (CD). However, budesonide has not been approved, and mesalazine is widely used as first-line treatment in Japan. The objective of this study was to evaluate the efficacy and safety of budesonide in patients with mild-to-moderate active CD in Japan. METHODS: In this phase 3 noninferiority study (NCT01514240), 112 patients with a baseline Crohn's Disease Activity Index (CDAI) score of 180-400 were randomized to budesonide or mesalazine for 8 weeks. Assessments included remission rate (CDAI score ≤150) at weeks 2, 4, and 8, change in CDAI score, health-related quality of life (measured using the Inflammatory Bowel Disease Questionnaire [IBDQ]), and tolerability. RESULTS: The remission rate at week 8 was numerically higher in the budesonide group (30.4%) than in the mesalazine group (25.0%), and the noninferiority of budesonide to mesalazine was shown. The mean total CDAI score decreased to a greater extent with budesonide than with mesalazine. Mean IBDQ scores improved from baseline to weeks 2, 4, 8, and 10 in both groups; improvements were numerically higher with budesonide than with mesalazine. No safety concerns were found. CONCLUSION: Budesonide is comparably effective to mesalazine in the treatment of Japanese patients with mild-to-moderate active CD.