P417. Multicenter, double-blinded, randomized, placebo-controlled, parallel-group study: evaluation of efficacy of mesalazine suppository in patients with ulcerative colitis with rectal inflammation
K. Matsuoka1, M. Watanabe2, T. Hibi1, 1Keio University School of Medicine, Gastroenterology and Hepatology, Tokyo, Japan, 2Tokyo Medical and Dental University, Gastroenterology and Hepatology, Tokyo, Japan
The ECCO guidelines recommend a mesalazine suppository as the standard remission induction and maintenance therapy for patients with proctitis. Previous clinical studies evaluated the efficacy of mesalazine suppositories only in patients with proctitis. The present study was therefore designed to confirm the efficacy of a mesalazine suppository not only in patients with proctitis, but in all types of UC patients with rectal inflammation.
The study was performed as a Phase III multicenter, double-blinded, randomized, placebo-controlled, parallel-group study. Included in the study were UC patients who have a rectal mucosal score of 2 or higher and a proximal mucosal score of less than 2, as evaluated by the Mayo endoscopic subscore at the start of treatment. They were randomly assigned to either 1 g mesalazine suppository or placebo suppository. The suppository was administered in the rectum once daily for 4 weeks. The primary endpoint was the endoscopic remission rate of the rectum (rate of patients with a mucosal score of 0 or 1) at 4 weeks of treatment.
This study was performed in 45 Japanese medical institutions from March 2011 to October 2011. Out of a total of 129 patients randomized to the mesalazine (65 patients) or placebo (64 patients) suppository. 73 patients had proctitis, and 56 patients had colonic inflammation proximal to the rectum. All the patients were included in the efficacy analysis population.
The endoscopic remission rate at 4 weeks of treatment was 81.5% and 29.7% in the mesalazine and placebo suppository groups, respectively. This result verified the superiority of the mesalazine suppository over placebo (p < 0.0001). In patients with proctitis, clinical remission rate was observed in 67.6% and 22.2% in the mesalazine and placebo suppository groups, respectively (p < 0.001). Also in patients with colonic inflammation proximal to the rectum, the clinical remission rate was significantly higher (57.1%) in the mesalazine suppository group than in the placebo group (10.7%) (p < 0.001).
The efficacy of the mesalazine suppository in all types of UC patients with rectal inflammation was confirmed for the first time in the present study. The mesalazine suppository is considered to increase patient satisfaction and greatly contribute to the improvement of quality of life.
Study registration: This study was registered at a clinical study site (JapicCTI-111421).
Financial support: This study was led by Kyorin Pharmaceuticals.