Oral pentasa in the treatment of active Crohn's disease: A meta-analysis of double-blind, placebo-controlled trials

Background & Aims: The aim of this study was to perform a meta-analysis of the efficacy results from 3 placebo-controlled multicenter clinical trials of slow-release mesalamine (Pentasa) for the acute treatment of mild to moderate Crohn's disease. Methods: Three trials fulfilled the selection criteria (double-blind, placebo-controlled, randomized studies in adult patients treated with Pentasa 4 g/day for active Crohn's disease). The efficacy and safety was evaluated in these trials by using the Crohn's Disease Activity Index (CDAI) as the primary efficacy variable. The study duration was 16 weeks in all 3 trials. The total numbers of patients were 304 in the Pentasa 4-g/day treatment groups and 311 in the placebo groups. A meta-analysis was performed based on the study reports. Results: For the intent-to-treat patients in the Pentasa groups, the overall mean reduction of the CDAI from baseline to the final visit was -63 points. The corresponding CDAI change in the placebo groups was -45 points; the net difference was -18 points. Compared with placebo, the 4-g/day dose of Pentasa was associated with a statistically significant overall improvement in the CDAI from baseline to the final visit (P = 0.04). When the meta-analysis was restricted to protocol correct patients, the effect of Pentasa became more pronounced (overall mean reduction of -83 CDAI points; P = 0.02, compared with placebo). Contrary to the consistent effects with Pentasa, the trial-specific reductions of the CDAI with placebo differed significantly between the trials. Conclusions: The meta-analysis of 3 large, double-blind, randomized studies in the treatment of active Crohn's disease confirms that Pentasa 4 g/day is superior to placebo in reducing the CDAI but the clinical significance of the magnitude of this difference is not clear.