FDA Approves Ironwood's (IRWD) LINZESS for Children Aged 2-5 with Functional Constipation

The U.S. Food and Drug Administration approved Ironwood Pharmaceuticals' (NASDAQ: IRWD) drug LINZESS to treat functional constipation in children aged 2 to 5 years, the company said May 28, 2026. The decision marks the first FDA clearance for a prescription therapy in this pediatric age group. LINZESS, a guanylate cyclase-C agonist, was previously approved for adults and children 6 years and older with irritable bowel syndrome with constipation and chronic idiopathic constipation. The expanded label now covers one of the youngest patient populations, opening a new commercial opportunity for Ironwood as it seeks to broaden revenue streams. The company did not disclose financial terms or sales projections tied to the approval. Functional constipation affects millions of U.S. children, and no FDA-approved prescription medication existed for the 2-5 age range until now. Ironwood shares rose 1.8% in premarket trading following the announcement.