Can oral 5-aminosalicylic acid be administered once daily in the treatment of mild-to-moderate ulcerative colitis? A meta-analysis of randomized-controlled trials.

OBJECTIVES: Several trials have demonstrated that oral delayed-release mesalamine might be administered once daily. We aimed to conduct a meta-analysis to investigate this. METHODS: A comprehensive and multiple-source literature search was carried out. Only randomized-controlled trials (RCTs) were investigated by comparing a once daily-dosing regime with a divided (twice or thrice daily)-dosing regime of oral delayed-release mesalamine formulations for induction or maintenance of remission in patients with mild-to-moderate ulcerative colitis. The quality of RCTs was assessed using the Jadad scores. Meta-analysis of pooled odds ratios was carried out using Review Manager 5.1. RESULTS: Nine RCTs were finally included. With regard to meta-analyses for induction trials, there were no significant differences for all comparisons between the once daily and the divided groups, including maintenance of just clinical remission (P=0.52) and just endoscopic remission (P=0.23), maintenance of combined clinical and endoscopic remission (P=0.78), and the overall incidence of adverse events (P=0.61). With regard to meta-analyses for maintenance trials, there were also no significant differences for all comparisons between once daily and divided groups, including maintenance of just clinical remission (P=0.73) and just endoscopic remission (P=0.43), maintenance of combined clinical and endoscopic remission (P=0.43), the overall incidence of adverse events (P=0.12) as well as compliance with the prescribed medication (P=0.34). CONCLUSION: The present work showed that oral delayed-release mesalazine administered as a single or a divided dose demonstrated a good safety profile, which was well tolerated and effective as either maintenance or induction treatment. High clinical and/or endoscopic remission rates can be achieved with once-daily dosing.