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

This study has been completed.
Sponsor:
Collaborator:
Cystic Fibrosis Foundation
Information provided by (Responsible Party):
Vertex Pharmaceuticals Incorporated
ClinicalTrials.gov Identifier:
NCT00953706
First received: August 4, 2009
Last updated: April 22, 2014
Last verified: April 2014
Results First Received: February 27, 2012  
Study Type: Interventional
Study Design: Allocation: Randomized;   Endpoint Classification: Safety/Efficacy Study;   Intervention Model: Parallel Assignment;   Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor);   Primary Purpose: Treatment
Condition: Cystic Fibrosis
Interventions: Drug: Ivacaftor
Drug: Placebo

  Participant Flow
  Hide Participant Flow

Recruitment Details
Key information relevant to the recruitment process for the overall study, such as dates of the recruitment period and locations
Part A started on 21 September 2009 (date of first informed consent). After obtaining consent and assent (where applicable), screening evaluations were completed during a period of 2 to 5 weeks (Day -35 to Day -15) before the first dose of study drug.

Pre-Assignment Details
Significant events and approaches for the overall study following participant enrollment, but prior to group assignment
In Part A, a total of 140 subjects were enrolled. All received at least 1 dose of the study drug. A 2-week run-in period was included to establish the baseline assessments on Day 1 after ensuring that subjects were properly adhering to their cystic fibrosis (CF) medication regimens.

Reporting Groups
  Description
Placebo Oral tablet every 12 hours (q12h) for 16 weeks
150 mg Ivacaftor q12h Oral tablet of 150 mg of ivacaftor q12h for 16 weeks

Participant Flow:   Overall Study
    Placebo     150 mg Ivacaftor q12h  
STARTED     28 [1]   112 [2]
COMPLETED     26 [3]   104 [3]
NOT COMPLETED     2     8  
Adverse Event                 2                 3  
Lost to Follow-up                 0                 1  
Noncompliance with Study Requirements                 0                 2  
Prohibited Medication                 0                 1  
Early Termination Per Sponsor Decision                 0                 1  
[1] All subjects who received at least 1 dose of study drug (placebo)
[2] All subjects who received at least 1 dose of study drug (ivacaftor)
[3] Completed Part A Treatment Period (Through Week 16)



  Baseline Characteristics
  Hide Baseline Characteristics

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
No text entered.

Reporting Groups
  Description
Placebo Oral tablet every 12 hours (q12h) for 16 weeks
150 mg Ivacaftor q12h Oral tablet of 150 mg of ivacaftor q12h for 16 weeks
Total Total of all reporting groups

Baseline Measures
    Placebo     150 mg Ivacaftor q12h     Total  
Number of Participants  
[units: participants]
  28     112     140  
Age  
[units: years]
Mean ± Standard Deviation
  25.0  ± 8.35     22.8  ± 10.26     23.2  ± 9.91  
Age, Customized  
[units: participants]
     
12 to 17 Years     6     44     50  
18 to 24 Years     10     32     42  
25 to 39 Years     12     26     38  
40 to 45 Years     0     5     5  
> 45 Years     0     5     5  
Gender  
[units: participants]
     
Female     12     54     66  
Male     16     58     74  
Race/Ethnicity, Customized  
[units: participants]
     
Hispanic or Latino     1     2     3  
Not Hispanic or Latino     27     110     137  
Race/Ethnicity, Customized  
[units: participants]
     
Black or African American     0     1     1  
White     28     111     139  
Percent Predicted Forced Expiratory Volume in 1 Second (FEV1), Continuous [1]
[units: percentage]
Mean ± Standard Deviation
  74.8  ± 24.06     79.7  ± 22.67     78.7  ± 22.95  
Percent Predicted FEV1, Categorical [1]
[units: participants]
     
< 70%     15     38     53  
≥ 70% to ≤ 90%     5     35     40  
> 90%     8     39     47  
Weight  
[units: kilograms]
Mean ± Standard Deviation
  63.2  ± 14.96     58.2  ± 13.49     59.2  ± 13.89  
Body Mass Index  
[units: kilogram per square meter]
Mean ± Standard Deviation
  22.2  ± 4.48     21.2  ± 3.25     21.4  ± 3.54  
Sweat Chloride  
[units: millimoles per liter]
Mean ± Standard Deviation
  102.4  ± 7.91     101.4  ± 10.28     101.6  ± 9.83  
[1] Percent predicted for age, gender, and height.



  Outcome Measures
  Show All Outcome Measures

1.  Primary:   Absolute Change From Baseline in Percent Predicted Forced Expiratory Volume in 1 Second (FEV1) Through Week 16   [ Time Frame: baseline through 16 weeks ]

2.  Secondary:   Absolute Change From Baseline in Cystic Fibrosis Questionnaire-Revised (CFQ-R) Score Through Week 16 (Respiratory Domain Score, Pooled)   [ Time Frame: baseline through 16 weeks ]

3.  Secondary:   Absolute Change From Baseline in Sweat Chloride Concentration Through Week 16   [ Time Frame: baseline through 16 weeks ]
  Hide Outcome Measure 3

Measure Type Secondary
Measure Title Absolute Change From Baseline in Sweat Chloride Concentration Through Week 16
Measure Description The sweat chloride (quantitative pilocarpine iontophoresis) test is a standard diagnostic tool for cystic fibrosis (CF), serving as an indicator of cystic fibrosis transmembrane conductance regulator (CFTR) activity.
Time Frame baseline through 16 weeks  
Safety Issue No  

Population Description
Explanation of how the number of participants for analysis was determined. Includes whether analysis was per protocol, intention to treat, or another method. Also provides relevant details such as imputation technique, as appropriate.
All randomized subjects who received at least 1 dose of study drug (ivacaftor or placebo) and had available assessments during the time frame.

Reporting Groups
  Description
Placebo Oral tablet every 12 hours (q12h) for 16 weeks
150 mg Ivacaftor q12h Oral tablet of 150 mg of ivacaftor q12h for 16 weeks

Measured Values
    Placebo     150 mg Ivacaftor q12h  
Number of Participants Analyzed  
[units: participants]
  28     111  
Absolute Change From Baseline in Sweat Chloride Concentration Through Week 16  
[units: millimoles per liter]
Least Squares Mean ± Standard Error
  0.1  ± 1.2     -2.7  ± 0.6  


Statistical Analysis 1 for Absolute Change From Baseline in Sweat Chloride Concentration Through Week 16
Groups [1] All groups
Method [2] Mixed Models Analysis
P Value [3] 0.0384
Mean Difference (Final Values) [4] -2.9
Standard Error of the mean ± 1.4
95% Confidence Interval ( -5.6 to -0.2 )
[1] Additional details about the analysis, such as null hypothesis and power calculation:
  Analysis for this variable was similar to that of the primary analysis of the primary efficacy endpoint. Estimates were from Mixed-Effects Model for Repeated Measures (MMRM) with dependent variable being absolute change from baseline, fixed effects for categorical visit and treatment group, and adjustment for continuous age and baseline value for age, sweat chloride, using unstructured covariance matrix.
[2] Other relevant method information, such as adjustments or degrees of freedom:
  No text entered.
[3] Additional information, such as whether or not the p-value is adjusted for multiple comparisons and the a priori threshold for statistical significance:
  No text entered.
[4] Other relevant estimation information:
  No text entered.



4.  Secondary:   Rate of Change From Baseline in Weight Through Week 16   [ Time Frame: baseline to 16 weeks ]


  Serious Adverse Events


  Other Adverse Events


  Limitations and Caveats
  Hide Limitations and Caveats

Limitations of the study, such as early termination leading to small numbers of participants analyzed and technical problems with measurement leading to unreliable or uninterpretable data
This study was primarily designed to collect safety information for subjects treated with ivacaftor and was not powered to detect a statistically significant treatment effect in any efficacy endpoints.


  More Information
  Hide More Information

Certain Agreements:  
Principal Investigators are NOT employed by the organization sponsoring the study.
There IS an agreement between Principal Investigators and the Sponsor (or its agents) that restricts the PI's rights to discuss or publish trial results after the trial is completed.
The agreement is:
unchecked The only disclosure restriction on the PI is that the sponsor can review results communications prior to public release and can embargo communications regarding trial results for a period that is less than or equal to 60 days. The sponsor cannot require changes to the communication and cannot extend the embargo.
unchecked Other disclosure agreement that restricts the right of the PI to discuss or publish trial results after the trial is completed.


Results Point of Contact:  
Name/Title: Medical Monitor
Organization: Vertex
phone: 617-444-6777
e-mail: medicalinfo@vrtx.com


No publications provided by Vertex Pharmaceuticals Incorporated

Publications automatically indexed to this study:

Responsible Party: Vertex Pharmaceuticals Incorporated
ClinicalTrials.gov Identifier: NCT00953706     History of Changes
Other Study ID Numbers: VX08-770-104
Study First Received: August 4, 2009
Results First Received: February 27, 2012
Last Updated: April 22, 2014
Health Authority: United States: Food and Drug Administration