Mesalazine granules 1.5 g once-daily maintain remission in patients with ulcerative colitis who switch from other 5-ASA formulations: a pooled analysis from two randomised controlled trials.

Background: Mesalazine (mesalamine) granules (MG) were shown to be effective for the maintenance of remission of ulcerative colitis (UC) in two double-blind placebo-controlled trials.

Aim: To evaluate the efficacy of once-daily MG for maintenance of remission in patients with UC who switched from other 5-aminosalicylic acid (5-ASA) formulations.

Methods: Data from two independent multicenter, randomised, double-blind, placebo-controlled, 6-month trials evaluating patients with UC in remission were combined for analysis of a subpopulation of patients who switched from other 5-ASA formulations to MG 1.5 g or placebo upon randomisation. The primary endpoint was the percentage of patients who remained relapse-free at Month 6 or end of treatment. Relapse was defined as a Sutherland Disease Activity Index (SDAI) rectal bleeding score ≥1 and mucosal appearance score ≥2, a UC flare or medication used to treat a UC flare.

Results: Of the 487 patients who received 5-ASA maintenance therapy at enrolment, 322 were in the MG group and 165 were in the placebo group. The percentage of patients who remained relapse-free (based on Sutherland Disease Activity Index scores) after 6 months was significantly higher with MG than placebo (78.3% vs. 58.8%, P < 0.001). Rectal bleeding, stool frequency and the physician's rating of disease activity remained unchanged after 6 months in a higher percentage of patients using MG compared with those on placebo (P < 0.004 for each endpoint).

Conclusion: Mesalazine granules 1.5 g once-daily is effective for maintenance of remission in UC patients who switch from other 5-ASA formulations. ClinicalTrials.gov identifiers NCT00744016, NCT00767728.