Patients with irritable bowel syndrome (IBS) had significant improvements in bowel habits and reductions in abdominal pain after taking a new drug called linaclotide, reports a study published in the December issue of Gastroenterology.
Jeffrey M. Johnston et al. performed a placebo-controlled phase 2 trial of 4 different doses of linaclotide in 420 patients with IBS and constipation. All doses significantly reduced pain, bloating, and constipation compared with placebo within the first week; improvements continued for the 3 months of the trial. The only adverse event was mild to moderate diarrhea.
Linaclotide binds and activates the guanylate cyclase-C (GC-C) receptor on the luminal surface of intestinal enterocytes to increase intracellular cGMP levels; this opens anion channels, increasing fluid secretion into the intestinal lumen and accelerating fluid transit. Linaclotide has also been shown to have anti-pain effects in animal models.
The 300 µg/day dose of linaclotide will be further evaluated in patients with IBS and constipation in phase 3 trials. Click here for a list of clinical trials of linaclotide for IBS.
Further Reading on Linaclotide:
- Harris LA. Constipation: linaclotide—a stimulating new drug for chronic constipation. Nature Reviews Gastroenterology and Hepatology 2010;7(7):365-366.
Read the article online:
Johnston JM, Kurtz CB, MacDougall JE, et al. Linaclotide improves abdominal pain and bowel habits in a phase IIb study of patients with irritable bowel syndrome with constipation. Gastroenterology 2010;139:1877–1886.e2.