On May 3, 2023, Vertex announced the Food and Drug Administration (FDA) ha approved KALYDECOﾮ (ivacaftor) for use in children with cystic fibrosis (CF) ages 1 month to less than four months old who have at least one mutation in their cystic fibrosis transmembrane conductance regulator (CFTR) gene that is responsive to KALYDECOﾮ based on clinical and/or in vitro assay data. KALYDECOﾮ is already approved in the U.S. and EU for the treatment of CF in patients ages four months and older.