FDA Approves Cystic Fibrosis Treatment

Drug targets the cause of the disease in people who have two copies of a specific mutation.

Drug targets the cause of the disease in people who have two copies of a specific mutation.

The FDA today approved the first cystic fibrosis treatment that targets the cause of the disease in people with 2 copies of a specific mutation.

Orkambi (lumacaftor 200 mg/ivacaftor 125 mg) was approved for cystic fibrosis patients 12 years and older with the F508del mutation. The mutation causes an abnormal protein to be produced, disrupting how water and chloride are transported through the body.

Inheriting one copy of the mutation from each parent is the leading cause of cystic fibrosis.

“The FDA encourages manufacturers to develop new and innovative treatments for serious rare diseases like cystic fibrosis,” said John Jenkins, MD, director of the Office of New Drugs, Center for Drug Evaluation and Research, in a press release. “Today’s approval significantly broadens the availability of targeted treatments for the specific defects that cause cystic fibrosis.”

Orkambi, which received priority review, was granted breakthrough therapy designation following preliminary clinical evidence that it may provide substantial improvement over current available treatments. The drug also received orphan drug designation, which offers incentives such as clinical trial tax credits and user fee waivers.

Orkambi was evaluated in a pair of double-blind, placebo-controlled clinical trials with 1108 cystic fibrosis patients 12 years and older with the F508del mutation. Patients in both studies received 2 Orkambi pills every 12 hours. The patients in both studies achieved improved lung function compared with patients who took placebo.

The efficacy and safety of the drug has only been established in cystic fibrosis patients with the F508del mutation. If the genotype is unknown, an FDA-approved cystic fibrosis mutation test should be used to detect whether the F508del mutation is present on both alleles of the CFTR gene.

Adverse events most commonly reported with Orkambi include shortness of breath, upper respiratory tract infection, nausea, diarrhea, and rash. In addition, women who took Orkambi experienced increased menstrual abnormalities, such as increased bleeding.