A Phase 2a, Multicenter, Randomized, Double-Blind, Parallel-Group, Placebo-Controlled Trial of IBD98-M Delayed-Release Capsules to Induce Remission in Patients with Active and Mild to Moderate Ulcerative Colitis

IBD98-M is a delayed-release formulation of mesalamine (mesalazine) and SH with a potential therapeutic role in ulcerative colitis (UC). A total of 51 patients with a modified Ulcerative Colitis Disease Activity Index (UCDAI) score of ≥4 and ≤10, and a modified UCDAI endoscopy subscore ≥1 were randomized for 6 weeks of double-blind treatment with IBD98 0.8 g/day or IBD 1.2 g/day or placebo. The efficacy and safety of IBD98-M in mild to moderate active UC were primarily evaluated. At week 6, 1 (5.9%), 2 (12.5%), and 2 (11.1%) patients receiving IBD98-M 0.8 g, IBD98-M 1.2 g, and placebo, respectively, (p > 0.999) achieved clinical remission. Higher clinical response was seen in IBD98-M 1.2 g (31.3%) versus placebo (16.7%) and endoscopic improvement in IBD98-M 0.8 g (29.4%) versus placebo (22.2%) was seen. Fecal calprotectin levels were reduced in IBD98-M groups versus placebo (p > 0.05). IBD98-M patients achieved significant improvement in physical health summary score component of the SF-36 (p = 0.01 and p = 0.03 respectively) compared to placebo. IBD98-M did not meet the primary end point but had higher clinical response (1.2 g/day) and endoscopic improvement (0.8 g/day) compared to placebo. The safety result shown that IBD98-M treatment was safe and well tolerated in this patient population. No new safety signals or unexpected safety findings were observed during the study. Further trials with different stratification and longer follow-up may be needed to evaluate the efficacy.