Trial results
AI generated results summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
According to the results reported on ClinicalTrials.gov, this trial enrolled 52 people in total — 26 received a placebo (a dummy treatment with no active ingredient) and 26 received a medicine called ivacaftor (150 mg twice daily). All 26 participants in the ivacaftor group completed the study, while 22 of the 26 in the placebo group did so. The trial was measuring several things over up to 48 weeks, with the main focus being lung function — specifically a breathing test called FEV1, which measures how much air a person can forcefully breathe out in one second, expressed as a percentage of what would be expected for someone of their age and size. The reported data shows that, for the primary measure (change in lung function up to Week 24), the placebo group's FEV1 score changed by an average of +0.1 percentage points from their starting level, while the ivacaftor group's score changed by an average of +12.6 percentage points. At Week 48, the reported figures were +0.7 percentage points for the placebo group and +10.7 percentage points for the ivacaftor group. The trial also measured a quality-of-life questionnaire score (on a scale of 0–100 for breathing-related wellbeing), with the ivacaftor group showing a reported change of around +6.3 points at Week 24 and +6.1 points at Week 48, compared with +0.3 and +1.0 points respectively for the placebo group. Additionally, a sweat chloride test (a marker related to how the condition affects salt in the body) showed a reported change of around −55.5 mmol/L for the ivacaftor group versus −1.2 mmol/L for placebo at Week 24, and −56.0 versus −2.6 mmol/L at Week 48. Finally, average weight gain was reported as 3.7 kg for the ivacaftor group versus 1.8 kg for the placebo group at Week 24, and 5.9 kg versus 3.1 kg at Week 48. These are the results as reported to ClinicalTrials.gov. They are not medical advice — always discuss what they mean for you with your doctor.
View full results on ClinicalTrials.gov ↗ · Read the linked publication on PubMed (PMID 23590265) ↗
These are the results as reported to ClinicalTrials.gov, not medical advice. Verify independently with the trial site and discuss what they mean for you with your doctor.
Phase 3 Cystic Fibrosis Trial, Completed
Who may be able to join
AI generated eligibility summary. Written by an AI model from the official source data and checked on a sample basis. It can contain mistakes, so confirm anything important against the original source. How we use AI
Who might be able to join this trial:
- You weigh at least 15 kg (about 33 pounds)
- You have a confirmed diagnosis of cystic fibrosis (CF) with a specific genetic mutation called G551D in at least one copy of the relevant gene
- Your lung function test (measuring how much air you can breathe out in one second) falls between 40% and 105% of what is normal for your age, gender, and height
- You are able to swallow tablets
- You (and your parent or legal guardian, if applicable) are able to understand and follow the study's requirements and complete the study as planned
- Your parent or legal guardian has signed a consent form, and you have given your own agreement to take part
- You are willing to use at least one reliable form of birth control throughout the study
- You have no significant health abnormalities that would interfere with the study, as decided by the study doctor
Who may not be able to join:
- You have a history of any illness or condition that could affect the study results or make taking the study drug risky for you
- You have had a lung infection, a worsening of lung symptoms, or a change in your lung treatments within the 4 weeks before the study starts
- Your liver function tests show results 3 or more times higher than the normal upper limit
- Your kidney function tests show abnormal results at the initial screening visit
- You have previously had a transplant of a solid organ (such as a kidney or liver) or bone marrow/blood cells
- You are currently taking part in another clinical drug trial, or have done so within the 30 days before screening
- You are currently using inhaled saltwater (hypertonic saline) as a treatment
- You are taking any medications that are known to strongly affect the way the body processes certain drugs (specifically, inhibitors or inducers of an enzyme called CYP 3A4) (confirm with trial site)
Important: Always verify eligibility with the trial site directly before applying.
Based on publicly available eligibility criteria from ClinicalTrials.gov. Verify directly with the trial site before acting. This is not medical advice.
Contact this trial
Principal Investigator: Richard Ahrens, MD, Roy A. & Lucille A. Carver College of Medicine
Australian sites
Contact details sourced from ClinicalTrials.gov. Verify directly with the trial site before attending.
GP referral letter
Print a one-page summary to share with your doctor.
Trial details
Where this trial is recruiting
4 site(s) in Australia. Confirm current status and contact details directly with the trial site.
Primary endpoints
Absolute Change From Baseline in Percent Predicted Forced Expiratory Volume in 1 Second (FEV1) Through Week 24
Can't join this trial?
Data last synced from ClinicalTrials.gov: 27 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.