Q&A: LinZess reduces bloating, pain in patients with IBS-C
Compared with placebo, LinZess significantly decreased abdominal symptoms such as bloating, discomfort and pain in patients with irritable bowel syndrome with constipation, according to results published in the American Journal of Gastroenterology.
Lin Chang, MD, professor of medicine and vice-chief, Vatche and Tamar Manoukian Division of Digestive Diseases, David Geffen School of Medicine at University of California, Los Angeles, and colleagues, randomly assigned patients with IBS-C to LinZess (linaclotide, Ironwood Pharmaceuticals) 290 g or placebo daily for 12 weeks. Investigators derived patients’ Abdominal score for bloating, discomfort and pain at their worst using patients’ reports in a Diary for IBS Symptoms-Constipation. Change from baseline in Abdominal score served as the primary endpoint. Other end points inlcuded change from baseline at 12 weeks using cumulative distribution function and 6-week/12-week abdominal score responder.

Healio Gastroenterology spoke with Chang on the results of linaclotide in patients with IBS-C.
Healio: What advice would you give patients suffering from IBS, will linaclotide change patient care?
Chang: There are several effective treatment options that range from diet to over the counter remedies to prescription medications. Patients who have IBS should see their health care provider to learn more about available treatments. Optimal treatment is determined based on the patient’s predominant and most bothersome symptoms. For example, if a patient has symptoms of IBS with predominantly constipation, linaclotide is an effective treatment that can reduce key abdominal symptoms including pain, bloating and discomfort as well as their constipation symptoms.
Healio: What are the key take-aways from the study?
Chang: This is the first large, clinical trial that used a novel, multi-item Abdominal score that measured the key bothersome abdominal symptoms, ie, pain, bloating and discomfort, and showed that linaclotide significantly reduced these abdominal symptoms in patients with IBS with constipation compared with placebo. The novel Abdominal score is included in the Diary for IBS Symptoms-Constipation (DIBSS-C), which is a validated patient reported outcome (PRO) tool that has been developed using the FDA’s guidance for PROs using good measurement principles. It is an abdominal symptom score that will be preferentially used in future IBS clinical trials.
Healio: What is the conclusion?
Chang: Linaclotide is an effective medication to treat IBS with constipation to not only relieve constipation symptoms but also bothersome abdominal pain, bloating and discomfort. These symptoms impact the overall severity of symptoms, health-related quality of life, and can be challenging to treat. The improvement of these symptoms by linaclotide were shown to be clinically meaningful with the use of the validated, multi-item Abdominal score.
Healio: What is the next step in research?
Chang: Future research includes studying the use of this novel PRO instrument in other large scale IBS treatment trials, measuring the efficacy of linaclotide using the DIBSS-C in specific patient populations, ie, elderly, pediatric patients, and based on race/ethnicity. Also identifying biologic markers associated with abdominal score response to treatment.