FDA approves linaclotide (Linzess) for pediatric patients aged 7 years and older with IBS-C

The FDA has approved linaclotide (Linzess; Ironwood Pharmaceuticals) capsules for pediatric patients aged 7 years and older with irritable bowel syndrome with constipation (IBS-C). Linaclotide is the first treatment approved for IBS-C in this age group.¹

IBS-C is a common condition in children and adolescents characterized by chronic constipation, abdominal pain, and bloating. It is defined by infrequent, hard stools that may be painful to pass and has no known organic cause. Multiple factors are typically involved in its onset and persistence.

Phase 3 evidence supports safety and efficacy

The approval builds on findings from a phase 3 double-blind, placebo-controlled, multicenter trial published in The Lancet Gastroenterology & Hepatology that evaluated linaclotide for functional constipation in pediatric patients aged 6 to 17 years (NCT04026113). The study included 328 participants who received linaclotide 72 mcg or placebo for 12 weeks, with the primary endpoint being the spontaneous bowel movement (SBM) frequency rate.²

Compared with placebo, linaclotide demonstrated a statistically significant and clinically meaningful improvement in bowel movement frequency. Linaclotide-treated patients achieved a greater than 2-fold least squares mean change from baseline in SBMs per week (2.220) vs placebo (1.050) (P < .0001). Stool consistency, measured by the Bristol Stool Form Scale, also improved with linaclotide at week 12. A greater increase in complete SBMs per week was observed in the linaclotide group compared with placebo (least squares mean change from baseline difference = 0.96; 95% CI, 0.51–1.40; P < .0001).

The percentage of patients who had at least 1 SBM within 24 or 48 hours after the first dose was significantly higher with linaclotide than with placebo (24 hours: 30.5% vs 20.7% [P = .043]; 48 hours: 56.7% vs 38.4% [P = .0009]).

“Functional constipation is among the most common complaints pediatricians and pediatric GIs see in our patients,” said Miguel Saps, MD, chief of the Division of Pediatric Gastroenterology, Hepatology, and Nutrition and the George E. Batchelor Endowed Chair in Pediatrics, University of Miami Health System. “The insights provided by the additional efficacy endpoints in this phase [3] clinical trial are an important supplement to clinicians’ knowledge about the available treatment options for this population.”

Kirk Thame, MD, associate professor of pediatric gastroenterology, hepatology, and nutrition at Monroe Carell Jr. Children’s Hospital at Vanderbilt, Nashville, Tennessee, noted, “All the issues you have with a liquid medicine will go away for children who can take tablets.”³

Safety profile and dosing

The most commonly reported treatment-emergent adverse event among pediatric patients receiving linaclotide was diarrhea, which occurred in 4% (7 of 164) of participants. The FDA noted that “the safety of Linzess in these clinical studies was similar in adult and pediatric patients.” Patients should discontinue linaclotide and be rehydrated if severe diarrhea occurs.

Linzess should not be used in patients younger than 2 years because of the risk of serious dehydration or in those with known or suspected mechanical gastrointestinal obstruction. The recommended dosage for pediatric patients 7 years and older with IBS-C is 145 mcg orally once daily.

Authors of the phase 3 study concluded that “linaclotide is an efficacious and well-tolerated treatment for functional constipation in [pediatric] patients and has subsequently been approved by the [FDA] for this indication.”

Clinicians are advised to review the full prescribing information for Linzess for additional details on dosing and safety.

Reference

1. FDA Approves 1st Drug for Children 7 Years and Older with Irritable Bowel Syndrome with Constipation. FDA. Press release. November 5, 2025. Accessed November 5, 2025.
2. Di Lorenzo C, Khlevner J, Rodriguez-Araujo G, et al. Efficacy and safety of linaclotide in treating functional constipation in paediatric patients: a randomised, double-blind, placebo-controlled, multicentre, phase 3 trial. The Lancet Gastroenterology & Hepatology. doi:10.1016/S2468-1253(23)00398-9
3. Fitch, J. How linaclotide can change the functional constipation treatment landscape. Contemporary Pediatrics. June 13, 2023. Accessed January 10, 2023. https://www.contemporarypediatrics.com/view/how-linaclotide-can-change-the-functional-constipation-treatment-landscape