Study of Ivacaftor in Subjects With Cystic Fibrosis (CF) Who Have the R117H-CF Transmembrane Conductance Regulator (CFTR) Mutation (KONDUCT) (KONDUCT)

• Absolute Change From Baseline in Percent Predicted Forced Expiratory Volume in 1 Second (FEV1) Through Week 24 [ Time Frame: Baseline, Week 24 ]
  FEV1 is the volume of air that can forcibly be blown out in one second, after full inspiration. Hankinson and Wang standards were used to calculate percent predicted FEV1 (for age, gender, and height). The Hankinson standard was used for male subjects 18 years and older and female subjects 16 years and older. The Wang standard was used for male subjects aged 6 to 17 years and for female subjects aged 6 to 15 years.
  
  

• Change From Baseline in Body Mass Index (BMI) at Week 24 [ Time Frame: Baseline, Week 24 ]
  BMI was defined as weight in kilogram (kg) divided by height in square meter (m^2).
  
  
• Change From Baseline in Sweat Chloride Through Week 24 [ Time Frame: Baseline, Week 24 ]
  Sweat samples were collected using an approved Macroduct (Wescor, Logan, Utah) collection device. A volume of greater than or equal to (>=) 15 microliter was required for determination of sweat chloride.
  
  
• Change From Baseline in Cystic Fibrosis Questionnaire-Revised (CFQ-R) Respiratory Domain Score Through Week 24 [ Time Frame: Baseline, Week 24 ]
  The CFQ-R is a validated subject-reported outcome measuring health-related quality of life for subjects with cystic fibrosis. Respiratory domain assessed respiratory symptoms (for example, coughing, congestion, wheezing), score range: 0-100; higher scores indicating fewer symptoms and better health-related quality of life
  
  
• Time to First Pulmonary Exacerbation [ Time Frame: Day 0 to 15, Day 16 to 56, Day 57 to 112, Day 113 to 168 ]
  Number of events (pulmonary exacerbation) during the pre-specified time intervals were reported. A subject without an exacerbation before withdrawal from the study was considered censored at the time of withdrawal, and a subject without an exacerbation who completes the study period was considered censored at the end of the analysis period.
  
  
• Number of Subjects With Adverse Events (AEs) and Serious Adverse Events (SAEs) [ Time Frame: Baseline up to follow-up (3 to 4 weeks after last dose [last dose = Week 24]) ]
  AE: any untoward medical occurrence, including clinically significant clinical laboratory assessments which occurs during course of study, whether it is considered related to study drug or not. SAE: medical event or condition, which falls into any of following categories, regardless of its relationship to the study drug: death, life threatening adverse experience, in-patient hospitalization/prolonged hospitalization, persistent/significant disability/incapacity, congenital anomaly/birth defect, important medical event.
  
  

Ivacaftor is the first CFTR modulator to show an improvement in CFTR function and clinical benefit in subjects with CF. Results from Phase 3 studies (VX08-770-102 [Study 102] [NCT00909532] and VX08-770-103 [Study 103] [NCT00909727]) showed that ivacaftor is effective in the treatment of subjects with CF who have the G551D-CFTR mutation, as evidenced by sustained improvements in CFTR channel function (measured by reduction in sweat chloride concentration) and corresponding substantial, durable improvements in lung function, pulmonary exacerbations, respiratory symptoms, and weight gain. Ivacaftor was also well tolerated, as evidenced by the rates and reasons for premature discontinuation and results of safety assessments.

Ivacaftor (Trade Name Kalydeco; 150 mg tablets) was initially approved in the United States for the treatment of CF in subjects 6 years of age and older who have a G551D mutation in the CFTR gene.