What the trial was testing
The trial enrolled 225 patients with cystic fibrosis. The study was sponsored by Vertex Pharmaceuticals and tracked outcomes across the full group of patients who matched the trial's eligibility profile.
It was an early-stage trial — researchers are still confirming safety and getting an early look at how well the treatment works. Trials at this stage are designed to produce evidence regulators and physicians can act on — not just observations to follow up later.
What the results showed
Lung function jumped 13.8 percentage points in people with one hard-to-treat mutation.
New England Journal of Medicine · 2018 · NCT03227471
These findings — that improvement in lung function (FEV1) for people with one Phe508del and a minimal-function mutation — were published in the New England Journal of Medicine and represent the headline result of the study.
Researchers tracked outcomes across 225 patients enrolled in the trial. The result was consistent enough across the group that the team felt confident reporting it.
What this means for patients
For patients with cystic fibrosis, this result changes the calculus on what to ask their care team about. Whether it changes day-to-day care depends on factors like disease subtype, prior treatments, and where the patient is in their care journey.
What you can do now
Elexacaftor-tezacaftor-ivacaftor (Trikafta) is FDA-approved and available now for people 2 and older with cystic fibrosis who carry at least one Phe508del mutation — about 90% of patients. Most U.S. CF centers prescribe it as standard care. Ask your CF team if your specific mutation qualifies.
Eligibility for the treatments mentioned above depends on specific test results and clinical history. Bring this summary, the trial name, and your most recent labs or pathology report to your next visit.
Open cystic fibrosis trials
Study to Enable New Diagnostics for Pulmonary Microbes in People With CF
Sputum culture has been the best approach to detect harmful bacteria in the lungs of people with cystic fibrosis (CF). With the widespread use of new CF therapies (like Trikafta and Alyftrak), it is more difficult for people with CF to produce sputum even though they still have harmful bacteria in their lungs. The SEND-CF study is being done to see if there are other ways to detect harmful bacteria in the lungs.
Safety, Tolerability and Efficacy Study of ARCT-032 in People With Cystic Fibrosis
ARCT-032-02 is a Phase 2, open-label, multicenter, multiple-ascending dose study of ARCT-032 in adults with CF who are not eligible for CFTR modulator therapy or are not taking CFTR modulators due to drug intolerance, poor response, or lack of access to modulators.