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Clinical Trials

Ironwood Pharmaceuticals starts Phase IIIb study of linaclotide in adult patients with IBS-C

Published 17 July 2018

Ironwood Pharmaceuticals has started a phase IIIb clinical trial evaluating the efficacy and safety of linaclotide 290 mcg on multiple abdominal symptoms in addition to pain, including bloating and discomfort, in adult patients with irritable bowel syndrome with constipation (IBS-C).

 Linaclotide is a guanylate cyclase-C (GC-C) agonist approved by the U.S. Food and Drug Administration (FDA) for the treatment of adults with IBS-C or chronic idiopathic constipation (CIC).

“There are an estimated 13 million adult IBS-C patients in the U.S., and more than two thirds of them report suffering from symptoms such as abdominal bloating and discomfort at least once per week. These symptoms are often a primary complaint and reason for patients seeking care,” said Christopher Wright, M.D., Ph.D., senior vice president, global development and chief development officer at Ironwood.

“As IBS-C patients often describe their abdominal symptoms as bloating or discomfort, rather than pain, this can lead to under-treatment. If positive, we believe these data should further enable more effective communication between patients and physicians on both IBS-C and the role that linaclotide can play in treating the millions of appropriate patients suffering from IBS-C.”

The randomized, double-blind, placebo-controlled, parallel-group study aims to enroll approximately 600 adult IBS-C patients in the United States. Eligible patients will be randomized to placebo or linaclotide 290 mcg once daily for 12 weeks, followed by a four-week randomized withdrawal period.

The primary efficacy endpoint is change from baseline in abdominal score based on daily patient assessments of abdominal bloating, discomfort, and pain at their worst, as reported on an 11-point numerical rating scale.

Additional endpoints include change from baseline in spontaneous bowel movement (SBM) frequency, complete spontaneous bowel movement (CSBM) frequency, stool consistency, and straining.

The clinical trial is being conducted jointly by Ironwood and Allergan plc, Ironwood's co-development and co-promotion partner for linaclotide in the United States.

Linaclotide is a guanylate cyclase-C (GC-C) agonist that binds to the GC-C receptor locally, within the intestinal epithelium.

Linaclotide is marketed by Ironwood and Allergan plc in the United States as LINZESS and is indicated for the treatment of adults with irritable bowel syndrome with constipation (IBS-C) or chronic idiopathic constipation (CIC), with greater than 2 million unique patients in the United States having filled approximately 10.6 million linaclotide prescriptions since launch, according to IQVIA. In Europe, Allergan markets linaclotide under the brand name CONSTELLA® for the treatment of adults with moderate to severe IBS-C.

Source: Company Press Release