Boswellia serrata extract for the treatment of collagenous colitis. A double-blind, randomized, placebo-controlled, multicenter trial.

BACKGROUND AND AIMS

The objective of this study was to investigate the effect of Boswellia serrata extract (BSE) on symptoms, quality of life, and histology in patients with collagenous colitis.

MATERIALS AND METHODS

Patients with chronic diarrhea and histologically proven collagenous colitis were randomized to receive either oral BSE 400 mg three times daily for 6 weeks or placebo. Complete colonoscopy and histology were performed before and after treatment. Clinical symptoms and quality of life were assessed by standardized questionnaires and SF-36. The primary endpoint was the percentage of patients with clinical remission after 6 weeks (stool frequency<or=3 soft /solid stools per day on average during the last week). Patients of the placebo group with persistent diarrhea received open-label BSE therapy for a further 6 weeks.

RESULTS

Thirty-one patients were randomized; 26 patients were available for per-protocol-analysis. After 6 weeks, the proportion of patients in clinical remission was higher in the BSE group than in the placebo group (per protocol 63.6%; 95%CI, 30.8-89.1 vs 26.7%, 95%CI, 7.7-55.1; p=0.04; intention-to-treat 43.8% vs 26.7%, p=0.25). Compared to placebo, BSE treatment had no effect on histology and quality of life. Five patients discontinued BSE treatment prematurely. Discontinuation was due to adverse events (n=1), unwillingness to continue (n=3), or loss to follow-up for unknown reasons (n=1). Seven patients received open-label BSE therapy, five of whom achieved complete remission.

CONCLUSIONS

Our study suggests that BSE might be clinically effective in patients with collagenous colitis. Larger trials are clearly necessary to establish the clinical efficacy of BSE.