FDA approves Linzess to treat certain cases of IBS and constipation

FDA approved linaclotide (Linzess, Ironwood Pharmaceuticals and Forest) to treat chronic idiopathic constipation and to treat irritable bowel syndrome with constipation (IBS-C) in adults.

According to the National Institutes of Health, an estimated 63 million people are affected by chronic constipation. Chronic idiopathic constipation is a diagnosis given to those who experience persistent constipation and do not respond to standard treatment. Additionally, an estimated 15.3 million people are affected by IBS. IBS-C is a subtype characterized mainly by abdominal pain and by hard or lumpy stools at least 25% of the time and loose or watery stools less than 25% of the time.

Linaclotide is a capsule taken once daily on an empty stomach, at least 30 minutes before the first meal of the day. Linaclotide helps relieve constipation by helping bowel movements occur more often. In IBS-C, it may also help ease abdominal pain.

“No one medication works for all patients suffering from these gastrointestinal disorders,” Victoria Kusiak, MD, deputy director of the Office of Drug Evaluation III in FDA’s Center for Drug Evaluation and Research, said in an FDA news release. “With the availability of new therapies, patients and their doctors can select the most appropriate treatment for their condition.”

The safety and effectiveness of linaclotide for the management of IBS-C were established in two double-blind studies. A total of 1,604 patients were randomly assigned to take 290 µg of linaclotide or a placebo for at least 12 weeks. Results showed linaclotide was more effective in reducing the amount of abdominal pain and increasing the number of complete spontaneous bowel movements compared with placebo.

The safety and effectiveness of linaclotide for the management of chronic idiopathic constipation also were established in two double-blind studies. A total of 1,272 patients were randomly assigned to take linaclotide at doses of 145 µg or 290 µg or a placebo for 12 weeks. Results from these studies showed patients taking linaclotide experienced more complete spontaneous bowel movements than those taking the placebo. The 290- µg dose is not approved for chronic constipation because studies indicated it was no more effective than the 145-µg dose.

Linaclotide is approved with a Boxed Warning to alert patients and healthcare professionals that the drug should not be used in patients aged 17 years and younger. The most common side effect reported in during the clinical studies was diarrhea.