FDA Updates Black Box Warning for Linzess

The update indicates there is a serious risk of dehydration and is contraindicated in children.

The FDA has approved a revised label for Ironwood Pharmaceutical’s Linzess (linaclotide) based on clinical safety data that has been generated from pediatric studies. The updated label modifies the boxed warning for risk of serious dehydration and contraindicated in children two years and above.

The boxed warning and contraindication previously applied to all children less than 18 years of age and less than 6 years of age, respectively. The label continues to include a boxed warning for children less than two years of age and a contraindication against use in this population.

Linzess is used to treat adults for irritable bowel syndrome with constipation and chronic idiopathic constipation.

“The warning on the Linzess label at launch was primarily applied due to preclinical findings, and there was an absence of any clinical data in pediatric populations at the time,” Michael Shetzline, M.D., Ph.D, chief medical officer, senior vice president and head of drug development at Ironwood, said in statement. “Since approval, we have worked diligently on generating clinical data to better characterize the safety profile for pediatric populations.

In May 2021, Ironwood announced that, with its partner AbbVie, the companies have entered into a settlement agreement with Teva Pharmaceuticals, providing a license to Teva to develop a generic version of 72 mcg Linzess and market the therapy beginning March 31, 2029.

Previously, Ironwood and Allergan granted Teva a license to market its 145 mcg and 290 mcg generic versions of Linzess in the United States beginning on the same date.