Safety and Patient Outcomes with Lubiprostone for Up to 52 Weeks in Patients with Irritable Bowel Syndrome with Constipation

Background: Irritable bowel syndrome with constipation (IBS-C) significantly decreases quality of life and the ability to perform daily living activities.

Aim: To demonstrate the long-term safety, tolerability and patient outcomes of lubiprostone in patients with IBS-C.

Methods: This extension study enrolled 522 IBS-C patients who had completed one of two randomised phase 3 studies. All enrolled patients received open-label lubiprostone orally for 36-weeks (8 mcg, twice daily). The primary objective was the assessment of long-term safety and tolerability, monitored via adverse events (AEs), laboratory parameters and vital signs. Additional outcome endpoints included monthly responder rates and patient evaluations of IBS-C symptom severity and impact on quality of life.

Results: The evaluable safety population comprised of 520 patients; 476 of which had patient reported outcome data available. The overall safety profile of lubiprostone during this study was similar to that observed in the preceding phase 3 studies. The most common AEs were diarrhoea (11.0%), nausea (11.0%), urinary tract infection (9.0%), sinusitis (9.0%) and abdominal distention (5.8%). Diarrhoea and nausea were the most common treatment-related AEs. No serious AEs were considered treatment-related. Seventeen patients discontinued due to a treatment-related AE, of which diarrhoea and nausea accounted for six (1.2%) and three (0.6%) respectively. For responder rates and patient-evaluated parameters (n = 476), all groups experienced significant improvements from baseline, with initial improvements maintained throughout the study.

Conclusion: In patients with irritable bowel syndrome with constipation, lubiprostone 8 mcg twice daily was found to be safe and well tolerated over 9-13 months of treatment.