The beneficial effect of azathioprine on maintenance of remission in severe ulcerative colitis.

Background: The search is on to find more effective drug regimens for patients with severe ulcerative colitis, as conventional drugs such as sulfasalazine and its congeners fail to prevent relapse in a significant number of patients. Azathioprine has also been reported to be useful as a steroid-sparing drug in patients who suffer from frequent relapses. As these drugs when used individually fail to sustain remission in a significant number of patients, we evaluated the combination of these two drugs.

Methods: Thirty-five newly diagnosed patients with severe ulcerative colitis were randomized into two groups; group A (combination therapy) received sulfasalazine and azathioprine, while group B (sulfasalazine monotherapy) received sulfasalazine and placebo. In addition, all the patients received steroids initially to achieve clinical remission. The patients were followed-up for a period of 1 year. The therapeutic outcome was measured by the number of patients who suffered relapse in each group.

Results: All the patients completed the 1-year study period. While 4 patients (23.5%) in group A suffered relapse of disease, 10 (55.6%) in group B suffered relapse, the difference being statistically significant. The relapse-free period was also significantly longer in group A.

Conclusions: Combination therapy (sulfasalazine and azathioprine) is more effective than sulfasalazine and placebo in the maintenance of remission in patients with severe ulcerative colitis.