By Tristan Manalac

On June 14, the FDA is set to release its verdict on Ironwood Pharmaceuticals’ supplemental New Drug Application (sNDA), in which the company proposes to use Linzess (linaclotide) for the treatment of functional constipation in kids and teens aged 6–17 years.
Ironwood is developing and commercializing Linzess in collaboration with AbbVie, following a 2015 agreement with Allergan. AbbVie acquired Allergan in 2019.
Linzess is a guanylate cyclase-C (GC-C) agonist that works by binding to the GC-C receptor within the intestinal epithelium, which in turn increases fluid secretion, faster transit and lower pain-sensing in the intestine. The drug won the FDA’s approval in August 2012 to treat patients with chronic idiopathic constipation and irritable bowel syndrome with constipation in adults.
Linzess’s label bears a boxed warning for risk of serious dehydration when used in children under two years of age.
Ironwood supported Linzess’ sNDA with data from a large Phase III study assessing the drug in pediatric patients. With 330 participants, the trial found that 12 weeks of Linzess treatment led to statistically significant and clinically meaningful improvements in spontaneous bowel movement, as compared with placebo.
Moreover, patients in the Linzess arm also saw better stool consistency at the 12-week follow-up. Ironwood’s drug was also safe, with the most common side effect being diarrhea.
When it accepted Ironwood’s sNDA, the FDA granted Linzess Priority Review, shortening its review time by four months.