Study of Ataluren (PTC124™) in Cystic Fibrosis

This study is a Phase 3, multicenter, randomized, double-blind, placebo-controlled, efficacy and safety study, designed to document the clinical benefit of ataluren when administered as therapy of participants with CF due to a nonsense mutation (premature stop codon) in the CFTR gene. It is planned that \~208 participants who are ≥6 years of age and have a forced expiratory volume in 1 second (FEV1) ≥40% and ≤90% of predicted will be enrolled. Study participants will be enrolled at sites in North America, Europe, and Israel. They will be randomized in a 1:1 ratio to either ataluren or placebo. Participants will receive study drug 3 times per day (at morning, midday, and evening) for 48 weeks. Participants will be evaluated at clinic visits every 8 weeks. Additional safety laboratory testing, which may be performed at the investigational site or at an accredited local laboratory or clinic, is required every 4 weeks for the first 6 months of study participation. At the completion of blinded treatment, all compliant participants will be eligible to receive open-label ataluren in a separate extension study.