Safety and Efficacy of Eluxadoline for Diarrhea-Predominant IBS

Eluxadoline — a poorly absorbed, orally administered opioid-receptor agonist/antagonist — has shown promise for improving diarrhea related to irritable bowel syndrome (IBS). Researchers now report on two manufacturer-funded, multicenter, randomized trials (primarily conducted in the U.S.) in which 2427 patients who had IBS with diarrhea received eluxadoline (75 mg or 100 mg twice daily) or placebo. One trial lasted 6 months, the other 1 year.

In both trials, eluxadoline significantly outperformed placebo on the primary endpoint (a composite response of reduced abdominal pain and improved stool consistency, or improved abdominal pain alone if no bowel movement). However, the overall response rates were low, and the difference between drug and…