FDA approves ivacaftor to treat infants with cystic fibrosis as young as 6 months

Vertex Pharmaceuticals announced that the FDA has approved ivacaftor for use in children with cystic fibrosis aged 6 to younger than 12 months who have at least one mutation in their cystic fibrosis transmembrane conductance regulator gene that is responsive to ivacaftor based on clinical and/or in vitro assay data.

Ivacaftor (Kalydeco) is already approved in the United States, Canada and the European Union for the treatment of cystic fibrosis in children aged at least 12 months, according to a company press release.

The new approval in infants was based on data from a 24-week, phase 3, open-label safety cohort (ARRIVAL) of 11 children with cystic fibrosis aged 6 to younger than 12 months who have one of 10 mutations in the CFTR gene (G551D, G178R, S549N, S549R, G551S, G1244E, S1251N, S1255P, G1349D or R117H). In the ARRIVAL cohort, treatment with ivacaftor in this population demonstrated a safety profile similar to that observed in previous phase 3 studies of older children and adults, according to the release. Most adverse events were mild or moderate and the most common events were cough (64%), nasal congestion (36%) and rhinorrhea (36%). The ARRIVAL data also highlighted a reduction in mean sweat chloride after 24 weeks of treatment. In the six infants with paired sweat chloride samples at baseline and 24 weeks, the mean absolute change was –58.6 mmol/L, according to the release.

Ivacaftor is an oral treatment that works to keep CFTR proteins at the cell surface open longer to improve the transport of salt and water across the cell membrane, which improves hydration and mucus clearing from the airways. This therapy is available as 25 mg, 50 mg and 75 mg granules in pediatric patients aged 6 months to younger than 6 years. In adults and children aged 6 years and older, ivacaftor is available as 150 mg tablets, according to the release.

“[The] approval for Kalydeco allows physicians to begin treating the underlying cause of [cystic fibrosis] in eligible infants as young as 6 months of age for the first time, with the potential to modify the course of disease,” Margaret Rosenfeld, MD, MPH, attending physician at Seattle Children’s Hospital and professor in the department of pediatrics at University of Washington School of Medicine, stated in the release.

Disclosure: Rosenfeld was a lead investigator in the ARRIVAL study, sponsored by Vertex Pharmaceuticals.