Mesalamine Capsules for Treatment of Active Ulcerative Colitis: Results of a Controlled Trial

The efficacy of a capsule formulation of mesalamine was assessed in 374 patients with mild to moderately active ulcerative colitis. Patients, stratified to pancolitis or left‐sided disease, received either placebo or mesalamine at 1, 2, or 4 g daily for 8 wk. Efficacy was assessed using clinical improvement—physician global assessment, sigmoidoscopic index, biopsy score, trips to the toilet, and clinical symptoms (abdominal pain, urgency, stool consistency, and rectal bleeding)—and induction of remission (more stringent criteria for physician global assessment, sigmoidoscopic index, and biopsy score). For physician global assessment of treatment benefit, 79% and 84% of patients on the 2‐g and 4‐g doses of mesalamine, respectively, received treatment benefit, compared with 54% on placebo (p < 0.0002). For the physician global assessment of treatment success, both the 2‐g and 4‐g doses of mesalamine were superior to placebo (57% and 59% of patients, p= 0.0021 and 0.0012, respectively), compared with 36% on placebo. Both the 2‐g and 4‐g doses produced statistically significant macroscopic (endoscopic) improvement compared with placebo (p < 0.004). The 4‐g dose also produced a statistically significant microscopic (histologic) improvement compared to placebo (p < 0.002). Significant improvement compared to placebo was also observed at 2 g and 4 g for the four clinical symptoms and trips to the toilet (p≤ 0.003). Oral mesalamine capsules were significantly superior to placebo for inducing remission, with 29% of patients at 2 g and 29% at 4 g achieving remission by physician global assessment, compared with 12% on placebo. Forty‐four percent and 48% of patients receiving 2 g and 4 g of mesalamine, respectively, achieved remission by sigmoidoscopic index (p < 0.05), compared with 31% on placebo. Thirty‐nine percent of patients at 4 g daily achieved microscopic remission, compared with 23% on placebo (p < 0.03). Treatment response was not affected by extent of disease or prior steroid or sulfasalazine therapy. These data suggest that con‐trolled‐release mesalamine capsules are a safe and effective monotherapy in doses of 2–4 g daily for treating mild to moderately active ulcerative colitis, as well as for inducing remission, regardless of prior oral steroid or sulfasalazine therapy or extent of disease.