Double-blind comparative study of sulfasalazine and controlled-release mesalazine tablets in the treatment of active ulcerative colitis.

To evaluate the effect of a controlled-release mesalazine tablet, in patients with ulcerative colitis (UC), a multicenter double-blind study was carried out, using sulfasalazine (500 mg tablet) as the control drug. The mesalazine tablet contained 250 mg of ethyl cellulose-coated mesalazine granules. The patients were assigned to two groups, one to receive mesalazine tablets (1500 mg/day) and a sulfasalazine placebo (group M) and the other to receive sulfasalazine tablets (3000 mg/day) and a mesalazine placebo (group S). The test medications were administered orally for 4 consecutive weeks. The study subjects were selected from among patients with mild to moderate active UC, and 118 patients were enrolled. Concomitant use of steroids and immunosuppressors was prohibited during the study period. Of the 118 patients, 9 dropped out. A total of 109 complete records were thus obtained, 52 in group M and 57 in group S. There was no difference in the improvement of clinical symptoms and endoscopic findings between the two groups. The overall safety, based on adverse reactions and laboratory data, was higher, at 86.5%, for group M (n = 52), compared to 66.7% for group S (n = 57). The general usefulness, based on the improvement and safety, was higher, at 65.3%, for group M (n = 49), compared to 45.6% for group S (n = 57). The controlled-release mesalazine tablet thus appears to be useful in the treatment of mild to moderate active UC.