The FDA recently announced the approval of a new therapy that treats Cystic Fibrosis (CF). The drug, called Orkambi, is manufactured by Boston-based Vertex Pharmaceuticals Inc. and treats the underlying cause of the disease in patients who have two copies of a certain mutation.
According to the FDA, Orkambi (lumacaftor 200 mg/ivacaftor 125 mg) can now be used as a treatment for CF patients 12 years and older who have the F508del mutation. The mutation causes the production of an atypical protein that is known to disrupt the way that chloride and water are transported in the body. The leading cause of CF is having two copies of the F508del mutation (one inherited from each parent).
“The FDA encourages manufacturers to develop new and innovative treatments for serious rare diseases like cystic fibrosis,” said in a recent press release John Jenkins, M.D., director of the Office of New Drugs, Center for Drug Evaluation and Research. “Today’s approval significantly broadens the availability of targeted treatments for the specific defects that cause cystic fibrosis.”
Orkambi’s approval was based on positive results in preliminary clinical studies that demonstrated the drug’s efficacy over currently available treatments. The FDA also reviewed Orkambi under the priority review program, which is used for specific drugs that may offer improvement in effectiveness or safety over available treatments in serious conditions. Orkambi was also granted FDA orphan drug designation because it treats a rare condition such as CF.
In the United States, Cystic Fibrosis affects approximately 30,000 people and is the most common fatal genetic condition in Caucasians. Half of the patients with CF in the U.S. have the F508del mutation.
Orkambi’s efficacy and safety was examined in two placebo-controlled, double-blind, clinical trials involving a total of 1,108 CF patients aged over 12 years with the F508del mutation. Patients received two pills daily for every 12 hours. Compared to the group of patients treated with a placebo, patients who received treatment with Orkambi demonstrated improved lung function.
Orkambi’s safety and efficacy has not been yet established in other groups of CF patients other than those with the F508del mutation. If a patient’s genotype is unspecified, an FDA-approved CF mutation test should be used to identify F508del mutation presence on both CFTR gene alleles.
The therapy’s most common adverse side events involve diarrhea, nausea, upper respiratory tract infection shortness of breath and rash. Orkambi also caused increased menstrual abnormalities including increased bleeding in some female study participants.