In a phase 3b trial, linaclotide more effectively reduced abdominal pain, bloating, and discomfort than placebo among patients with constipation-predominant irritable bowel syndrome (IBS-C). These findings were published in The American Journal of Gastroenterology.
Patients (N=614) with IBS-C were recruited for this multicenter, randomized, double-blind, placebo-controlled, parallel-group trial at 78 centers in the United States between 2018 and 2019 (ClinicalTrials.gov Identifier: NCT03573908). Participants were randomly assigned in a 1:1 ratio to receive 290 mg linaclotide (n=306) or placebo (n=308) for 12 weeks. An eDiary was maintained throughout the study, in which patients reported daily symptoms; abdominal score (AS) was calculated by averaging 10-point scores for abdominal bloating, discomfort, and pain.
Patients in the active and control cohorts were aged mean 46.5 and 46.8 years, 78.8% and 82.8% were women, body mass index (BMI) was 29.50 and 29.39 kg/m2, 61.8% and 64.3% were White, and IBS symptom severity was 3.59 and 3.62 points, respectively. The overall treatment compliance among all participants was 97%.
Linaclotide was associated with a greater reduction in AS scores (mean change from baseline [CFB], -1.9 vs -1.2; P <.0001). The difference between groups was observed at week 1 and continued through all pre-specified time points (all P <.0005).
Patients who received linaclotide were more likely to respond to treatment than placebo recipients (odds ratio [OR], 2.2; 95% CI, 1.55-3.12; P <.0001).
Separated by AS components, linaclotide more effectively reduced abdominal bloating (mean CFB, -1.9 vs -1.1; P <.0001), discomfort (mean CFB, -1.9 vs -1.2; P <.0001), and pain (mean CFB, -1.9 vs -1.2; P <.0001). However, linaclotide treatment did not decrease the percentage of days rescue medication was needed (P =.1632).
Treatment-emergent adverse events were experienced by 31.0% of linaclotide and 26.6% of placebo recipients. More individuals in the linaclotide group reported diarrhea (4.6% vs 1.6%).
This study may have been limited by the sex imbalance among participants; however, the study authors noted it is estimated that women seek care for IBS at a ratio of 2.5:1 compared with men.
These data indicate that abdominal pain, bloating, and discomfort associated with IBS-C can be more effectively reduced with linaclotide therapy.
Disclosure: Multiple authors declared affiliations with industry. Please refer to the original article for a full list of disclosures.
Chang L, Lacy BE, Moshiree B, et al. Efficacy of linaclotide in reducing abdominal symptoms of bloating, discomfort, and pain: a phase 3B trial using a novel abdominal scoring system. Am J Gastroenterol. 2021;116(9):1929-1937. doi:10.14309/ajg.0000000000001334