Phase 3 Cystic Fibrosis Trial, Completed NCT04599465 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 (NCT04599465) enrolled 69 people with cystic fibrosis, all of whom received a combination treatment called ELX/TEZ/IVA. Of those, 66 completed the study and 3 did not. The trial was measuring changes in blood sugar levels — specifically using a test called an oral glucose tolerance test (OGTT), where a person drinks a sugary drink and their blood sugar is measured two hours later. The study tracked these blood sugar readings over roughly 48 weeks. The reported data shows that, on average, participants' two-hour blood sugar readings after the OGTT dropped by 35 milligrams per deciliter (mg/dL) compared to where they started, measured as an average across week 36 and week 48. For context, a lower number on this test generally means lower blood sugar at that point in time. The reported data also shows that 37.7% of participants showed an improvement in how their blood sugar was categorised by week 48 — for example, moving from a diabetes classification to a lower-concern category, or from an in-between category to a normal range. On a separate safety-related measure, the reported data shows that 67 out of the 69 participants experienced at least one adverse event (an unwanted health experience during the study period), and 6 participants experienced a serious adverse event. The trial results do not allow us to draw conclusions about whether these events were caused by the treatment. 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

NCT04599465
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 carry a specific combination of cystic fibrosis gene changes — one copy of the "F508del" mutation and one copy of a so-called "minimal function" mutation
  • Your lung function test result (measuring how much air you can breathe out in one second) is at least 30% of what would be expected for someone your age, sex, and height
  • A sugar tolerance test (where you drink a sugary drink and have your blood sugar measured) has shown that your body has trouble processing sugar, either as "impaired glucose tolerance" (blood sugar is higher than normal but not yet at diabetes level) or as cystic fibrosis-related diabetes (CFRD), based on specific blood sugar readings during or after that test (confirm with trial site)

Who may not be able to join:

  • You have significant scarring of the liver (cirrhosis), with or without high blood pressure in the liver's blood vessels
  • You have had a transplant of a solid organ (such as a lung, kidney, or liver) or a blood/bone marrow transplant
  • You have a lung infection caused by certain bacteria that are known to cause faster decline in lung health (confirm with trial site for specific organisms)
  • You have been diagnosed with Type 1 or Type 2 diabetes (not cystic fibrosis-related diabetes)
  • You have had cystic fibrosis-related diabetes (CFRD) for 5 years or longer

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.

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 28 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

Royal Adelaide Hospital, Adelaide,
The Prince Charles Hospital, Chermside,
Alfred Hospital, Melbourne,
Telethon Kids Institute, Nedlands,
The Royal Children's Hospital, Parkville, VIC,
Sydney Children's Hospital, Randwick,
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
15 January 2021
Est. completion
14 July 2022

Where this trial is recruiting

🇦🇺 Australia 🇧🇪 Belgium 🇨🇿 Czechia 🇫🇷 France 🇮🇹 Italy 🇳🇱 Netherlands 🇪🇸 Spain

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

Primary endpoints

Change From Baseline in 2-hour Blood Glucose Levels Following an OGTT to the Average of Week 36 and Week 48

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: 28 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