A randomized, placebo-controlled, double-blind trial of mesalamine in the maintenance of remission of Crohn's disease. The Canadian Mesalamine for Remission of Crohn's Disease Study Group

Gastroenterology. 1997 Apr;112(4):1069-77. doi: 10.1016/s0016-5085(97)70117-3.


Background & aims: The efficacy of mesalamine for the maintenance of remission in patients with Crohn's disease is controversial. The aim of this study was to conduct a double-blind, placebo-controlled study of mesalamine (750 mg four times a day for 48 weeks) in maintaining remission in 293 patients with Crohn's disease. Patients were stratified according to the method of induction of remission (medical or surgical).

Methods: Patients were assessed at weeks 4, 12, 24, 36, and 48. Relapse was defined as a Crohn's Disease Activity Index of >150 (+60 points over baseline).

Results: Of the 293 patients, 246 (84%) returned for at least 4 weeks of follow-up and were included in the final analysis. Thirty of the 118 (25%) who received mesalamine had a relapse compared with 47 of 128 (36%) receiving placebo (P = 0.056). Among those with relapse, the time to relapse was 119 days for the mesalamine-treated patients compared with 109 days for placebo-treated patients (P = NS). However, 25% of mesalamine-treated patients had relapsed by 249 days of follow-up compared with 154 days for placebo-treated patients. Subgroup analysis showed that patients with ileocecal-colonic disease or patients who were women had fewer relapses on mesalamine therapy than placebo-treated patients (21% vs. 41%, P = 0.018; and 19% vs. 41%, P = 0.003, respectively).

Conclusions: Mesalamine treatment reduced relapse compared with placebo treatment, although conventional statistical significance was not achieved.

Publication types

  • Clinical Trial
  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aminosalicylic Acids / adverse effects
  • Aminosalicylic Acids / therapeutic use*
  • Anti-Inflammatory Agents, Non-Steroidal / therapeutic use*
  • Crohn Disease / drug therapy*
  • Double-Blind Method
  • Female
  • Humans
  • Male
  • Mesalamine
  • Recurrence
  • Treatment Outcome


  • Aminosalicylic Acids
  • Anti-Inflammatory Agents, Non-Steroidal
  • Mesalamine