Aims: The aim of this study is to assess the efficacy and safety of lubiprostone in adults with chronic constipation.
Methods: This multicenter, parallel-group trial enrolled 237 patients with chronic constipation and randomized them to 4 weeks of double-blind treatment with oral lubiprostone 24 mcg or placebo twice daily. The primary efficacy endpoint was the number of spontaneous bowel movements (SBMs) after 1 week of treatment. Secondary evaluations included SBMs at weeks 2, 3, and 4; percentage of patients with a SBM within 24 h of first study dose; stool consistency; degree of straining; constipation severity; abdominal bloating and discomfort; global treatment effectiveness; and safety assessments.
Results: Lubiprostone-treated patients experienced greater mean numbers of SBMs at week 1 compared with placebo (5.89 versus 3.99, P = 0.0001), with significantly greater percentages having SBMs within 24 h of the first dose (61.3% versus 31.4%, P < 0.0001). At each assessment, SBM frequency and percentages of full responders (> or =4 SBM per week) were significantly greater among lubiprostone-treated patients compared with placebo (P < or = 0.0171). Lubiprostone-treated patients reported significant improvements in stool consistency, straining, and constipation severity at all weeks, and in abdominal bloating at week 1. Patient assessments of treatment effectiveness were significantly greater with lubiprostone compared with placebo at all weeks (P < 0.0004). Gastrointestinal-related disorders were the most common adverse events in both treatment groups.
Conclusions: In patients with chronic constipation, lubiprostone produced a bowel movement in the majority of individuals within 24 h of initial dosing, with sustained improvement in frequency as well as other constipation symptoms over 4 weeks of treatment.