Randomised clinical trial: mesalazine versus placebo in the prevention of diverticulitis recurrence

BACKGROUND: Previous studies have reached conflicting conclusions regarding the efficacy of mesalazine in the prevention of recurrent diverticulitis. AIM: To investigate the efficacy and safety of mesalazine granules in the prevention of recurrence of diverticulitis after acute uncomplicated diverticulitis. METHODS: Two phase 3, randomised, placebo‐controlled, double‐blind multicentre trials (SAG‐37 and SAG‐51) investigated mesalazine granules in patients with prior episodes (<6 months) of uncomplicated left‐sided diverticulitis. Patients were randomised to receive either 3 g mesalazine once daily or placebo (SAG‐37, n=345) or to receive either 1.5 g mesalazine once daily, 3 g once daily or placebo for 96 weeks (SAG‐51, n=330). The primary endpoint was the proportion of recurrence‐free patients during 48 weeks (SAG‐37 and SAG‐51) or 96 weeks (SAG‐51) of treatment. RESULTS: Mesalazine did not increase the proportion of recurrence‐free patients over 48 or 96 weeks compared to placebo. In SAG‐37, the proportion of recurrence‐free patients during 48 weeks was 67.9% with mesalazine and 74.4% with placebo (P=.226). In SAG‐51, the proportion of recurrence‐free patients over 48 weeks was 46.0% with 1.5 g mesalazine, 52.0% with 3 g mesalazine and 58.0% with placebo (P=.860 for 3 g mesalazine vs placebo) and over 96 weeks 6.9%, 9.8% and 23.1% respectively (P=.980 for 3 g mesalazine vs placebo). Patients with only one diverticulitis episode in the year prior to study entry had a lower recurrence risk compared to >1 episode. Safety data revealed no new adverse events. CONCLUSION: Mesalazine was not superior to placebo in preventing recurrence of diverticulitis.