Evaluation of VX-121/Tezacaftor/Deutivacaftor in Cystic Fibrosis (CF) Participants 1 Through 11 Years of Age

The purpose of this study is to evaluate the pharmacokinetics, safety, tolerability and efficacy of VX-121/tezacaftor/deutivacaftor (VX-121/TEZ/D-IVA) in CF participants with at least 1 triple combination responsive (TCR) mutation in the cystic fibrosis transmembrane conductance regulator (CFTR) gene.

Key Inclusion Criteria: * Participants with stable CF and at least 1 TCR mutation (including F508del) in the CFTR gene Key Exclusion Criteria: * History of solid organ, hematological transplantation, or cancer * Hepatic cirrhosis with portal hypertension, moderate hepatic impairment (Child Pugh Score 7 to 9), or severe hepatic impairment (Child Pugh Score 10 to 15) * Lung infection with organisms associated with a more rapid decline in pulmonary status Other protocol defined Inclusion/Exclusion criteria may apply.