FDA has approved lumacaftor/ivacaftor (Orkambi, Vertex) for the treatment of cystic fibrosis in patients 12 years and older.
Cystic fibrosis (CF) is a rare, life-threatening genetic disease caused by defective or missing cystic fibrosis transmembrane conductance regulatory (CFTR) proteins due to mutations in the CFTR gene. The defective or missing proteins result in poor flow of water and chloride across cells that produce mucus, sweat, and digestive juices. These secretions then become thick and sticky and build up causing severe damage to the lungs and digestive system. Having 2 copies of the F508del mutation is the leading cause of CF. Of the 30,000 people in the United States with CF, approximately 8,500 have 2 copies of the F508del mutation.
Orkambi is the first drug approved to treat the underlying cause of CF in people aged 12 years and older who have 2 copies of the F508del mutation. It is only indicated for these patients, who can be identified with genetic testing. Orkambi is a combination of lumacaftor 200 mg and ivacaftor 125 mg which have complementary mechanisms of action that target the molecular defect and enhance the function of the mutated CFTR gene.
The approval of Orkambi was based on the results of 2 phase 3 studies that enrolled more than 1,100 CF patients aged 12 years and older with 2 copies of the F508del mutation. Patients treated with Orkambi experienced statistically significant improvements in lung function as well as reductions in pulmonary exacerbations and improvements in body mass index (BMI).
Orkambi received breakthrough therapy designation and was also reviewed under FDA’s priority review program. FDA also granted Orkambi orphan drug designation because it treats a rare disease.
Shortness of breath and/or chest tightness, upper respiratory tract infection, nausea, diarrhea, and rash, were the most common adverse reactions associated with using the drug. Women who took Orkambi also had increased menstrual abnormalities such as increased bleeding.