Abstract
Objective. Hyoscine butylbromide (HBB) has been used for 60 years to treat cramping abdominal pain, but scientific evidence to support on-demand use is limited. The aim of this study was to identify a meaningful efficacy end point that differentiates between the effects of HBB (20–100 mg/day) and placebo when used on demand. Materials & methods. 175 patients were treated in a randomized, double-blind, placebo-controlled, two-arm parallel group study. After a 4-week run-in period, patients used HBB to treat 2 distinct episodes of abdominal pain associated with cramping (APC). Patients entered data into an electronic diary for up to 4 h/episode. Pain intensity was assessed using an 11-point numerical pain rating scale (NPRS). Patients were allowed to self-medicate with up to 4 additional doses of HBB every 30 min. Results. The adjusted mean difference for the change from baseline during the 4-h observation period for a reduction in abdominal pain was -0.7 (95% confidence interval (CI) -1.3, -0.1, p = 0.016) for episode 1 and -0.6 (95% CI -1.2, 0.0, p = 0.051) for episode 2. Patients in the HBB group recorded a clinically relevant reduction of at least 2 points on the NPRS (approximately 30% pain relief) earlier than patients in the placebo group (HBB: 45 min, placebo: 60 min). Reported adverse events were infrequent in both groups (10.2% and 10.3%). Conclusions. HBB is effective in the treatment of recurrent APC and is safe and well tolerated when used on demand. The change from baseline in the intensity of APC using the 11-point NPRS distinguished HBB from placebo.
Acknowledgements
The authors are grateful to RTI Health Solutions (Research Triangle Park, NC, USA) for development of questionnaire in accordance with the FDA guideline, “Guidance for Industry – Patient-Reported Outcome Measures: Use in Product Development to Support Labelling Claims. Draft guidance, February 2006, and to PHT Corp. (Charlestown, MA, USA) for providing and managing the e-diary. The authors thank the principal investigators of the participating study sites for their valuable contribution and continuous support (in alphabetical order): Charles Andrews, Robert Barclay, Robert Bargar, Mira Baron, Deborah Camiscoli, David Eskries, Umesh Goswami, Michael Grossman, Lisa Harris, William Jennings, Rashid Khairi, Edward Portnoy, Michael Schwartz, Lawrence Seidman, Gregory Serfer, Ronald Surowitz, Lawrence Saubermann, Robert Hardi, Vasanth Siddalingaiah, Lisa Connery.
Declaration of interest: BE Lacy: no disclosures relevant to this study. Dr. Lacy did not receive any personal remuneration for participating in this study. F Wang, S Bhowal and E Schaefer: employees of Boehringer Ingelheim, Ridgefield, CT, USA and Ingelheim, Germany. This study was sponsored by Boehringer Ingelheim Pharmaceutical, Inc., Ridgefield, CT, USA.