A Study to Evaluate the Efficacy and Safety of VX-661 in Combination With Ivacaftor in Subjects Aged 12 Years and Older With Cystic Fibrosis, Heterozygous for the F508del-CFTR Mutation

Exclusion Criteria

• •History of any comorbidity that, in the opinion of the investigator, might confound the results of the study or pose an additional risk in administering study drug to the participant.
• •An acute upper or lower respiratory infection, pulmonary exacerbation, or changes in therapy (including antibiotics) for pulmonary disease within 28 days before Day 1 (first dose of study drug).
• •History of solid organ or hematological transplantation.
• •Ongoing or prior participation in an investigational drug study or use of commercially available CFTR modulator within 30 days of screening.
• •Pregnant or nursing females.