Background and aims: It is not clear what induction dose of mesalamine is optimal for treating patients with mildly and moderately active ulcerative colitis (UC). This study was conducted to determine the efficacy and safety of mesalamine 4.8 g/day compared with 2.4 g/day for the treatment of moderately active UC.
Methods: A multicenter, randomized, double-blind, 6-week, active-control study (ASCEND III) was conducted to assess the noninferiority of delayed-release mesalamine 4.8 g/day (Asacol HD, 800-mg tablet; Procter & Gamble, Pharmaceuticals, Inc, Mason, Ohio) with 2.4 g/day (Asacol, 400-mg tablet; Procter & Gamble Pharmaceuticals, Inc) in 772 patients with moderately active UC. The primary endpoint was treatment success (overall improvement) at week 6, defined as improvement in the Physician's Global Assessment (based on clinical assessments of rectal bleeding, stool frequency, and sigmoidoscopy), with no worsening in any individual clinical assessment.
Results: The primary objective of noninferiority was met. Seventy percent (273 of 389) of patients who received 4.8 g/day of mesalamine achieved treatment success at week 6, compared with 66% (251 of 383) of patients receiving 2.4 g/day (95% confidence interval for 2.4 g/day minus 4.8 g/day, -11.2 to 1.9). In addition, 43% of patients who received 4.8 g/day mesalamine achieved clinical remission at week 6 compared with 35% of patients who received 2.4 g/day (P = .04). A therapeutic advantage for the 4.8 g/day dose was observed among patients previously treated with corticosteroids, oral mesalamines, rectal therapies, or multiple UC medications. Both regimens were well-tolerated with similar adverse events.
Conclusions: Delayed-release mesalamine 4.8 g/day (800-mg tablet) is efficacious and well-tolerated in patients with moderately active UC.