COMPARISON OF TWO DIFFERENT FORMULATIONS OF MEBEVERINE HYDROCHLORIDE IN IRRITABLE BOWEL SYNDROME

Abstract

SUMMARYA total of 213 patients were recruited to a multicentre, randomised, double‐blind, double dummy, general practice study lasting eight weeks. The objectives of the study were (i) to demonstrate therapeutic equivalence of mebeverine hydrochloride 200 mg b.i.d. capsules (Colofac®MR) and 135 mg t.i.d. tablets (Colofac®) in the treatment of abdominal pain in irritable bowel syndrome (IBS) and (ii) to evaluate safety and physicians' and patients' assessments of therapeutic response. Patients were randomised at day 0 and assessments performed after four and eight weeks. Primary and secondary efficacy endpoints were number of responders (response being defined as 50% or more improvement in global mean visual analogue scale for abdominal pain); patients' and physicians' global assessment of therapeutic response; and physicians' global impression of patient symptoms. Safety was assessed from adverse event reports and routine laboratory tests. Therapeutic equivalence was proven statistically (difference <18%; p=0.003), with 65/92 (71%) of the 135 mg t.i.d. group and 64/92 (70%) of the 200 mg b.i.d. group classified as responders. The patients' evaluation of response (week 8) was that 75% of 135 mg t.i.d. and 81% of 200 mg b.i.d. improved; the physicians' assessment of therapeutic response (week 8) was that 64% of 135 mg t.i.d. and 70% of 200 mg b.i.d. had no or mild symptoms. In conclusion, Mebeverine hydrochloride 200 mg b.i.d. (Colofac®MR) was shown to be therapeutically equivalent to mebeverine hydrochloride 135 mg t.i.d. (Colofac®) in the treatment of abdominal pain in IBS. Results for the secondary efficacy variables were comparable. No safety concerns were identified.