Comparison of efficacy of once daily multimatrix mesalazine 2.4 g/day and 4.8 g/day with other 5-aminosalicylic acid preparation in active ulcerative colitis: A randomized, double-blind study

Background/Aims: This study compared the efficacy of multimatrix mesalazine 2.4 g/day and 4.8 g/day with controlled-release mesalazine 2.25 g/day. Methods: In this multicenter, randomized, double-blind study, 251 patients with mildly to moderately active ulcerative colitis received multimatrix mesalazine 2.4 g/day once daily (Multimatrix-2.4), 4.8 g/day once daily (Multimatrix-4.8), or controlled-release (time-dependent) mesalazine 2.25 g/day 3 times daily (Time-2.25) for 8 weeks. The primary efficacy endpoint was the change in the ulcerative colitis-disease activity index (UC-DAI) score. Results: The mean change in the UC-DAI score and standard deviation in the per protocol set was -1.9±2.5 for Multimatrix-2.4 and -2.4±2.8 for Time-2.25. The difference between Multimatrix-2.4 and Time-2.25 was 0.3 (two-sided 95% confidence interval [CI], -0.5 to 1.1), thus non-inferiority was not demonstrated based on the pre-defined non-inferiority margin (1.0). In the full analysis set, the difference between Multimatrix-4.8 and Time-2.25 was -1.2 (two-sided 95% CI, -2.0 to -0.5), and the mean change in UC-DAI score in the FAS was -3.3 (two-sided 95% CI, -3.9 to -2.8) for Multimatrix-4.8 and -1.9 (two-sided 95% CI, -2.5 to -1.3) for Multimatrix-2.4, indicating that Multimatrix-4.8 was more effective than Time-2.25 and Multimatrix-2.4. There was no difference among the treatment groups in terms of safety. Conclusions: This study showed that the efficacy of multimatrix mesalazine 2.4 g/day was comparable to controlled release mesalazine 2.25 g/day, although non-inferiority was not demonstrated. Importantly, this was the first study to indicate that multimatrix mesalazine 4.8 g/day was more effective than 2.4g/day with no associated safety concerns.