Efficacy and tolerability of two oral hyoscine butylbromide formulations in Chinese patients with recurrent episodes of self-reported gastric or intestinal spasm-like pain

Aim: To compare the efficacy and tolerability of oral hyoscine butylbromide tablets and capsules in Chinese patients with recurrent episodes of self-reported gastric or intestinal spasm-like pain and to show non-inferiority of both formulations. Methods: 302 patients were entered into a randomized, double-blind, double-dummy, active-controlled 2-arm parallel group study. They were randomized to 3 days of treatment with hyoscine butylbromide tablets or capsules. In patient diaries the pain intensity was assessed on 10 cm visual analogue scales on Day 1 (0, 30, 60, 90, 120, and 180 minutes after first dose), Days 2, and 3 (maximum pain intensity once daily). Pain frequency, overall efficacy, and tolerability were assessed on verbal rating scales. Results: In the per-protocol dataset 281 patients were analyzed. The change from baseline after 180 minutes was 59% in both treatment groups; the adjusted means of pain intensity on Day 1 were reduced by 2.36 cm (tablets) and -2.31 cm (capsules). Pain intensity decreased within 30 minutes by approximately 20%. The decrease of the peak pain intensity was approximately 55% after 3 days in both treatment groups; the adjusted means after 3 days were reduced by -2.48 cm (tablets) and by -2.45 cm (capsules). Abdominal pain frequency decreased by 50% (tablets) and 42% (capsules). Both treatments were well tolerated. Drug-related adverse events were infrequent (3.5%). No serious adverse event occurred. Conclusions: Hyoscine butylbromide is effective in the treatment of recurrent gastric or intestinal spasm-like pain and well tolerated. Non-inferiority of tablets and capsules was demonstrated.