Study of Ivacaftor in Cystic Fibrosis Subjects Aged 12 Years and Older Homozygous for the F508del-CFTR Mutation

This study investigated the effects of ivacaftor in participants with cystic fibrosis (CF)
>=12 years of age with a forced expiratory volume in 1 second (FEV1) >=40 percent (%)
predicted. This study was conducted in 2 parts.

- Part A of this study was a randomized, double-blind, placebo-controlled, parallel-group
evaluation of participants with CF who were aged 12 years or older and were homozygous
for the F508del-CFTR mutation.

- Part B of this study was an open-label extension of Part A, enrolling participants who
completed Part A and met pre-specified endpoint criteria, and explored the safety and
efficacy of ivacaftor over long-term treatment in participants with CF aged 12 years or
older who were homozygous for the F508del-CFTR mutation.

Inclusion Criteria:

- Confirmed diagnosis of cystic fibrosis (CF) and homozygous for F508del-CFTR mutation

- Forced expiratory volume in 1 second (FEV1) of at least 40% of predicted normal for
age, gender, and height

- Willing to use at least 2 highly effective birth control methods during the study

- No clinically significant abnormalities that would have interfered with the study
assessments, as judged by the investigator

- Able to understand and comply with protocol requirements, restrictions, and
instructions and likely to complete the study as planned, as judged by the
investigator

Exclusion Criteria:

- History of any illness or condition that might confound the results of the study or
pose an additional risk in administering study drug to the subject

- Acute respiratory infection, pulmonary exacerbation, or changes in therapy for
pulmonary disease within 4 weeks of Day 1 of the study

- History of alcohol, medication or illicit drug abuse within one year prior to Day 1

- Abnormal liver function >=3 x the upper limit of normal

- Abnormal renal function at Screening

- History of solid organ or hematological transplantation

- Pregnant or breast-feeding (for women)

- Ongoing participation in another therapeutic clinical study or prior participation in
an investigational drug study within 30 days prior to screening

- Previous participation in a VX-809 study

- Used inhaled hypertonic saline treatment

- Concomitant use of any inhibitors or inducers of cytochrome P450 3A4 (CYP3A4)