A Study Evaluating the Safety and Efficacy of VX-659 Combination Therapy in Subjects With Cystic Fibrosis

This is a Phase 2, randomized, double-blind, placebo- and tezacaftor/ivacaftor (TEZ/IVA)-controlled, parallel-group, 3-part, multicenter study designed to evaluate the safety and efficacy of VX-659 in triple combination (TC) with TEZ and IVA in subjects with cystic fibrosis (CF) who are homozygous for the F508del mutation of the CF transmembrane conductance regulator (CFTR) gene (F/F genotype), or who are heterozygous for the F508del mutation and a minimal function (MF) CFTR mutation not likely to respond to TEZ, IVA, or TEZ/IVA (F/MF genotypes).