Linaclotide improved abdominal pain in patients with IBS

SAN DIEGO — Patients with IBS experienced relief from abdominal pain after a linaclotide regimen regardless of the initial severity of their symptoms, according to data published at the 2012 Digestive Disease Week Annual Meeting.

In two phase 3 trials, patients with IBS and constipation (n=1,602) randomly received either placebo or 290 mcg linaclotide orally once daily for 12 weeks. Each participant rated their abdominal pain on a 10-point scale for the previous 24 hours each day. Researchers pooled data from the two studies and stratified participants according to their mean scores at baseline, with 649 reporting less than 5 (mean 3.9), 577 reporting 5 to 7 (mean 5.9) and 376 reporting 7 or greater (mean 8.0). The mean baseline score among all patients was 5.6. Participants also graded the relief of their symptoms each week on a 7-point scale, with a 1 indicating complete relief and a 7 indicating the worst pain imaginable.

Across all three groups, pain scores decreased by 29% to 36% in the linaclotide group, compared with 18% to 20% in the three placebo groups (P<.0001). Overall, the mean baseline score decreased by 32.2% in the treatment group and 18.9% in the placebo group (P<.0001). The linaclotide patients who reported their pain at 7 or greater experienced a 32.1% improvement to baseline score, compared with 18.7% among patients receiving placebo (P<.0001). Researchers also found a significant association between baseline scores and the absolute magnitude of improvement (r=0.26; P<.0001), but not the percent of improvement (r=0.00; P=.9184). Patient relief ratings also were significantly better in the treated group compared with the placebo group, both overall (2.9 vs. 3.5 P<.0001) and in each subgroup (P<.0001).

“Linaclotide improves abdominal pain in patients with IBS with constipation,” Philip S. Schoenfeld, MD, MEd, MSc, associate professor of medicine in the gastroenterology division at the University of Michigan School of Medicine, told Healio.com. “That improvement is maintained in patients with mild, moderate and severe abdominal pain, and is not just statistically significant, but clinically important. Most medicines that have been used for IBS usually have only improved pain in IBS patients with mild to moderate pain in clinical trials. Here, linaclotide seems to show even more improvement in abdominal pain compared with placebo as patients have more severe pain.”

For more information:

Schoenfeld PS. #Mo1856: Linaclotide Significantly Improved Abdominal Pain Compared With Placebo in Patients With Irritable Bowel Syndrome Regardless of Baseline Pain Severity in Two Phase 3 Trials. Presented at: the 2012 Digestive Disease Week Annual Meeting; May 19-22, San Diego.