High mucosal healing rates in 5-ASA-treated ulcerative colitis patients: results of a meta-analysis of clinical trials

Background: Recently, mucosal healing (MH) is regarded as an important treatment goal in ulcerative colitis (UC). 5-Aminosalicylates (5-ASA) are the standard treatment in mild-to-moderate UC, but the effect on MH is less known. The aim of this study was to systematically review the medical literature in order to compare different preparations of 5-ASA for the effect on MH.

Methods: We conducted a structured search of PubMed and the Cochrane Central Register of Controlled Trials to identify randomized controlled clinical trials with 5-ASA in UC providing data about MH. We calculated the sample size-weighted pooled proportion of patients with MH, and performed meta-analysis of head-to-head comparisons.

Results: Out of 645 hits, we included 90 treatment arms, involving 3977 patients using oral 5-ASA (granulate and tablets) and 2513 patients using rectal 5-ASA (suppositories, enema, and foam). Overall, 43,7% of 5-ASA treated patients achieved MH (oral 36,9%; rectal 50,3%). In oral studies, 49% of patients using granulate (7 treatment-arms) achieved MH compared to 34,9% using tablets (43 treatment-arms). In rectal studies the proportion of MH was 62% for suppositories (eight treatment arms), 51% for foam (nine treatment arms), and 46% for enema (23 treatment arms), respectively.

Conclusions: 5-ASA preparations achieved MH in nearly 50% of UC patients. There were no significant differences in MH between the various 5-ASA agents, either in the oral or the rectal treatment groups.