FDA Approves CF Treatment Kalydeco for Infants as Young as 4 Months

The U.S. Food and Drug Administration (FDA) has approved Vertex Pharmaceuticals‘ Kalydeco (ivacaftor) as a treatment for infants as young as four months with cystic fibrosis (CF) caused by certain mutations.

The approval makes Kalydeco the first medication in its class to be approved for such a young age group.

“Initiating therapy that treats the underlying cause of cystic fibrosis as early as four months of age may have the potential to modify the course of the disease,” Margaret Rosenfeld, MD, of the University of Washington School of Medicine, said in a Vertex press release.

JP Clancy, MD, vice president of clinical research at the Cystic Fibrosis Foundation, said in a separate press release: “We believe that people with CF will experience the maximum benefit from these therapies when they begin treatment early in life, before the disease has caused significant damage.”

CF is caused by mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene, which encodes a protein of the same name. Normally, the CFTR protein functions as a sort of “gate” on the surface of cells that can open and close to control the movement of charged salts, but in CF, the mutated protein does not function properly.

Kalydeco is a CFTR modulator, a type of medication that works to correct the underlying defect in the CFTR protein. Specifically, Kalydeco is a CFTR potentiator because it works on CFTR proteins where the “gate” has become “stuck closed.” By opening the gate, Kalydeco eases the transport of salts and water in and out of cells.

The treatment was first approved in the U.S. in 2012, with the FDA subsequently expanding that approval multiple times. Most recently, Kalydeco was approved for use in patients six months and older with one of 38 mutations that result in a “stuck closed” CFTR protein.

With this latest approval, the therapy is indicated for patients as young as four months who have these mutations.

“Since the initial approval of Kalydeco more than eight years ago, we have continued to advance our clinical development program with the goal of treating the underlying cause of cystic fibrosis as early in life as possible,” said Reshma Kewalramani, MD, Vertex’s CEO and president.

“Today’s approval is a testament to our relentless efforts, alongside the clinical and scientific community, to reach all people with CF who may benefit from our medicines,” she added.

The new approval was based on data from the Phase 3 open-label clinical trial ARRIVAL (NCT02725567), sponsored by Vertex. This trial included six CF infants from the age of 4 months up to 6 months, who were treated with Kalydeco. Safety data in these young children were consistent with what has been reported in other age ranges.

“Our hope is that those who start on modulators as infants may never experience many of the classic symptoms of CF, and we are committed to supporting ongoing research to better understand the impact of early treatment,” Clancy said.

Kalydeco use in CF infants as young as 4 months is currently being evaluated by the European Commission.