Canada Prioritizes Review of Kalydeco for Children With R117H Mutation

Health Canada has granted priority review to Vertex Pharmaceuticals’ application seeking the approval of Kalydeco (ivacaftor) to treat cystic fibrosis (CF) patients, ages 4 months to 18 years, carrying the R117H mutation in the CFTR gene.

The intended label extension is for patients who weigh at least 5 kilograms (about 11 pounds), according to the company’s press release.

“We are pleased this submission has been accepted for Priority Review by Health Canada, and we hope that this will enable access for patients with the R117H mutation as soon as possible,” said Duncan McKechnie, Vertex’s senior vice president, North America commercial operations.

The company’s supplement to the New Drug Submission for Kalydeco follows Health Canada’s recent decision to extend the use of this therapy to treat babies, starting at 4 months old, with the gating mutations G551D, G1244E, G1349D, G178R, G551S, S1251N, S1255P, S549N, and S549R. Kalydeco had been approved in Canada to treat children, starting at age 1, and adults with these mutations.

“It’s our goal to ensure as many people as possible with cystic fibrosis are able to access treatments for the underlying cause of their CF,” McKechnie added.

An application covering patients as young as 6 months with the R117H mutation already has been approved by the European Commission. In the U.S., Kalydeco became the first medication in its class to be approved for infants as young as 4 months.

CF is caused by mutations in the CFTR gene, which carries the instructions for making a protein with the same name. Acting as a “gate” in the cell membrane, the CFTR protein is key in helping maintain the flow of water and salts in and out of cells.

The different types of mutations in the CFTR gene impair the function or production of the this protein in different ways. In some CF-causing mutations, such as R117H, the CFTR gate is “stuck” closed, partially blocking the flow across the cell membrane, and leading to thick, sticky airway mucus.

Kalydeco is a CFTR potentiator, a type of CF treatment that works to open the gate in the CFTR protein, thereby normalizing the transport of salts and water in and out of cells.