Background: Mesalamine is released from sulfasalazine in the colon and benefits colonic Crohn's disease. The mesalamine used in this study releases the drug throughout the small bowel and colon. Therefore, this study was designed to detect benefit for Crohn's disease involving the small bowel alone or both the colon and small bowel.
Methods: This double-blind, randomized, multicenter prospective controlled trial compared placebo and three daily doses of mesalamine in 310 patients. The primary outcome criterion was change in the Crohn's Disease Activity Index (CDAI) from baseline to final study visit.
Results: Patients taking 4 g/day mesalamine experienced a decrease of 72 CDAI points compared with 21 points in the placebo group (P < 0.01). Remission occurred in 43% of the 4-g group and 18% of the placebo group. Patients with ileum-only disease showed a 93-point improvement on 4 g mesalamine, compared with a 2-point improvement in similar patients on placebo. Mesalamine in this trial was not associated with clinically significant toxicity.
Conclusions: This controlled-release mesalamine preparation is safe and effective at 4 g/day as a single agent in treatment of active Crohn's disease of the ileum and colon.