What the trial was testing
The EXTEND enrolled 1,131 patients with cystic fibrosis. The study was sponsored by Vertex Pharmaceuticals Incorporated and tracked outcomes across the full group of patients who matched the trial's eligibility profile.
It was a large trial designed to confirm whether the treatment works well enough for wider use. 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
The rate of lung function decline was 62% lower in treated patients versus untreated matched controls.
The Lancet. Respiratory medicine · 2021 · NCT02565914
These findings — that the drug combo slowed the loss of lung function by nearly two-thirds versus no treatment — were published in the The Lancet. Respiratory medicine and represent the headline result of the study.
Researchers tracked outcomes across 1,131 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
This treatment is FDA-approved and available now for people 12 and older with certain cystic fibrosis gene mutations (F508del). It helps slow lung damage over time. Ask your doctor if this combination is right for your specific gene type and whether it's covered by insurance.
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
Acoustic Waveform Respiratory Evaluation
The study will evaluate the feasibility of using smartphone speakers and microphones to evaluate the caliber of the airways, detect airway obstruction, aid in airway disease diagnosis, and identify disease exacerbations.
Understanding Inflammation, InFection and Interventions in Severe Exacerbations of Cystic Fibrosis
The UNIFIED-CF study is an observational study designed to investigate the impacts of treatment given for severe pulmonary exacerbations in people living with cystic fibrosis (pwCF). Exacerbations are episodes when pwCF become more unwell, typically characterised by increased cough, sputum, and breathlessness and treated with a combination of oral and/or intravenous antibiotics. Severe exacerbations require treatment with intravenous antibiotics and impart considerable morbidity on pwCF. In this study, the investigators will recruit people at risk of severe CF exacerbations when they are well and if/when they are subsequently admitted for treatment of an exacerbation, the investigators will track symptoms and lung function during recovery, and collect blood, sputum and stool samples to allow us to explore the biological mechanisms of exacerbations and how they relate to different treatment responses. The study is event driven and will complete recruitment once 125 participants have completed treatment and follow-up for a severe exacerbation event. This study is funded by the Cystic Fibrosis Trust. This study is part of a wider programme of research, led by the PULSE-CF Innovation Hub (and hosted by the University of Manchester). The aim of the Hub is that the data from the UNIFIED-CF study will ultimately support the design of a platform clinical trial to test exacerbation-prevention interventions in CF.