Agency says approval is the first for a drug that targets the defective CFTR protein.
FDA approved Vertex Pharmaceuticals’ Kalydeco™ (ivacaftor) as a treatment for cystic fibrosis (CF) patients six years and older who carry at least one copy of the G551D mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. This sanction represents the first for a CF drug designed to treat the underlying cause of CF, rather than just address the effects of disease. Kalydeco was discovered by Vertex through its collaboration with Cystic Fibrosis Foundation Therapeutics (CFFT), the nonprofit drug discovery and development affiliate of the Cystic Fibrosis Foundation.
Regulatory clearance of Kalydeco in the U.S. was based on data from two 48-week placebo-controlled Phase III studies in 213 CF patients who carried at least one G551D-mutated CFTR gene. The trial results confirmed that treatment led to significant, sustained improvements in lung function, fewer pulmonary exacerbations, and improved disease measures including weight gain. Vertex submitted a marketing authorization application to the European Medicines Agency (EMA) for Kalydeco In October 2011. “We now have a medicine that treats the underlying cause of the disease in people with the G551D mutation,” comments Robert J. Beall, Ph.D., president and CEO of the Cystic Fibrosis Foundation. “Kalydeco also provides us with a roadmap for exploring additional targeted approaches to treatment for all people with cystic fibrosis.”
Regulatory clearance of the drug in the U.S. was achieved in just three months under FDA’s priority review program, which Vertex claims is one of the fastest FDA approvals ever. “The unique and mutually beneficial partnership that led to the approval of Kalydeco serves as a great model for what companies and patient groups can achieve if they collaborate on drug development,” adds FDA Commissioner Margaret A. Hamburg, M.D.
Vertex says it aims to start new trials this year to evaluate Kalydeco in pediatric CF patients as young as two years old, and in people with CF who have the R117H mutation or gating mutations that were not evaluated in the previous Phase III studies.
Enrollment is also ongoing in the second stage of a Phase II clinical trial evaluating Kalydeco combined with the CFTR corrector VX-809, in CF patients with F508de, the most common mutation in CF. VX-809 was also developed through Vertex’ partnership with the CFFT. Vertex in addition aims to start Phase II development of VX-661, a second CFTR corrector, during the first quarter of 2012.