Two mesalazine regimens in the prevention of the post-operative recurrence of Crohn’s disease: a pragmatic, double-blind, randomized controlled trial

Background: The role of mesalazine in preventing the clinical recurrence of Crohn's disease after surgery has been shown in a meta-analysis of all published studies. No clear relationship, however, has been shown between dosage and response. Aim: To evaluate whether 4.0 g/day of mesalazine may offer therapeutic advantages over 2.4 g/day in the prevention of both endoscopic and clinical post-operative recurrence of Crohn's disease. Methods: The study was a double-blind, randomized, multi-centre, prospective, controlled clinical trial. Two hundred and six patients, submitted to first or second intestinal resection for Crohn's disease limited to the terminal ileum, with or without involvement of the caecum/ascending colon, were enrolled. Of these, 101 were randomly allocated to receive 4.0 g/day of mesalazine (Asacol, Giuliani SpA, Milan, Italy) and 105 to receive 2.4 g/day, starting 2 weeks after surgery. The primary outcome was endoscopic recurrence, at 12 months after surgery. Three different degrees of endoscopic recurrence were evaluated (endoscopic scores: > 0, > 1 and > 2). The secondary outcome was clinical recurrence, defined as a Crohn's disease activity index of more than 150 points or an increase in the Crohn's disease activity index of 100 points or more. For statistical analysis, chi-square, Wilcoxon and Cox regression model tests were used, when appropriate. Results: Eighty-four patients in the 4.0 g/day group and 81 patients in the 2.4 g/day group were evaluable by endoscopy. Endoscopic recurrence of > 0 was significantly higher in the 2.4 g/day group than in the 4.0 g/day group (62% vs. 46%; P 1 and > 2) or clinical recurrence. Conclusions: A 4.0 g/day regimen of mesalazine does not offer a clinically significant advantage over a 2.4 g/day regimen in the prevention of post-operative endoscopic and clinical recurrence of Crohn's disease at 1 year of follow-up