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.