Phase 3 Cystic Fibrosis Trial, Completed NCT04058353 Sponsor: Vertex Pharmaceuticals Incorporated Condition: Cystic Fibrosis
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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 (NCT04058353) enrolled 258 people with cystic fibrosis — 126 in a control group who continued taking an existing cystic fibrosis medicine (either ivacaftor alone or tezacaftor/ivacaftor), and 132 in a group who switched to a triple-drug combination called elexacaftor/tezacaftor/ivacaftor (ELX/TEZ/IVA). The trial was measuring changes in three things: lung function (specifically how much air someone can forcefully breathe out in one second, expressed as a percentage of what is expected for a healthy person of similar age and size — called ppFEV1), a sweat chloride level (a marker commonly measured in cystic fibrosis, where salt concentration in sweat is tested), and a self-reported quality-of-life score focused on breathing symptoms (scored from 0 to 100, where higher means fewer symptoms). The reported data shows that in the triple combination group, ppFEV1 changed by an average of +3.7 percentage points, compared to +0.2 percentage points in the control group. For sweat chloride, the triple combination group saw an average change of −22.3 mmol/L (a fall in the level), while the control group saw a change of +0.7 mmol/L. On the breathing symptom quality-of-life questionnaire, the triple combination group reported an average change of +10.3 points on the 0–100 scale, compared to +1.6 points in the control group. These are the numbers as submitted by the trial sponsor; no other outcome data was reported in the structured results. These are the results as reported to ClinicalTrials.gov. They are not medical advice — always discuss what they mean for you with your doctor.

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

NCT04058353
Completed Phase 3 🇦🇺 Australian site

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 have a confirmed diagnosis of cystic fibrosis (CF) and carry one copy of a specific gene change called F508del, along with a second specific type of gene change (called a "gating" or "residual function" mutation
  • Your lung function test results (a breathing test called FEV1) fall within a specific range — not too low and not too high — based on what is expected for your age, sex, and height

Who may not be able to join:

  • You have significant scarring or damage to your liver, with or without increased blood pressure in the liver's blood vessels
  • You have a lung infection caused by certain germs that are known to cause faster decline in lung health (confirm with trial site for which specific organisms apply)
  • You have previously received a transplant of a solid organ (such as a kidney, heart, or liver) or of blood-forming cells (such as a bone marrow transplant)

Important: There may be additional requirements not listed here. 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.

This is a simplified plain English summary of the eligibility criteria. Full criteria are set by the trial investigators and may include additional requirements not shown here. Never self-exclude from a trial based on this summary. Contact the trial site directly to confirm your eligibility.
Last synced 22 July 2026
Phase 3: approximately ~65% of drugs entering this phase reach regulatory approval, based on published industry-wide historical data. This is not specific to this trial.
Phase success rates shown are historical industry-wide averages based on published data. They are not a prediction for this specific trial or your individual situation.

Contact this trial

Australian sites

The Prince Charles Hospital, Chermside,
Alfred Hospital, Melbourne, VIC,
Perth Children's Hospital, Nedlands,
The Royal Children's Hospital, Parkville, VIC,
Mater Adult Hospital, South Brisbane,
Queensland Children's Hospital, South Brisbane,
Westmead Hospital, Westmead,

Contact details sourced from ClinicalTrials.gov. Verify directly with the trial site before attending.

GP referral letter

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Trial details

Status
Completed
Phase
Phase 3
Registry
ClinicalTrials.gov
Start date
28 August 2019
Est. completion
12 June 2020

Where this trial is recruiting

🇦🇺 Australia 🇧🇪 Belgium 🇨🇦 Canada 🇩🇰 Denmark 🇫🇷 France 🇩🇪 Germany 🇮🇪 Ireland 🇮🇱 Israel 🇮🇹 Italy 🇳🇱 Netherlands 🇪🇸 Spain 🇬🇧 United Kingdom 🇺🇸 United States

7 site(s) in Australia. Confirm current status and contact details directly with the trial site.

Primary endpoints

Absolute Change in Percent Predicted Forced Expiratory Volume in 1 Second (ppFEV1) for ELX/TEZ/IVA Group

Can't join this trial?

Expanded access pathways

If this trial is not available to you, other access pathways may exist. In Australia, the TGA Special Access Scheme allows access to unapproved therapeutic goods for individual patients.

TGA Special Access Scheme information

Find other recruiting trials on ClinicalTrials.gov

Data last synced from ClinicalTrials.gov: 22 July 2026. Trial status can change. Always verify current status directly with the trial site before making any decision.

Trial recruitment status can change without notice between our nightly data updates. Always contact the trial site directly to confirm current recruitment status before making any decisions or travel arrangements.

View original record on ClinicalTrials.gov