What the trial was testing
The SKYLINE enrolled 597 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 new once-daily pill worked just as well as the current standard treatment in maintaining lung function.
The Lancet. Respiratory medicine · 2025 · NCT05076149
These findings — that new pill worked as well with simpler dosing schedule — were published in the The Lancet. Respiratory medicine and represent the headline result of the study.
Researchers tracked outcomes across 597 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
If you have cystic fibrosis and are on Trikafta (the current standard), this new once-daily option could simplify your routine without sacrificing results. The treatment is not yet FDA-approved, but these strong results from a large trial suggest it may become available soon. Talk to your CF care team about whether this option might be right for you when it becomes available.
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
Studying the Presence of CFRD Complications With Thoughtful Recruitment (SPeCTRuM)
This multicenter cross-sectional study will include a diverse population of adolescents and adults with CF. The overall Aim is to describe prevalence of diabetes microvascular complications and macrovascular surrogates in people with established CFRD.
Identification of Dysglycemia With Continuous Glucose Monitoring to Assess Clinical Evolution in Cystic Fibrosis
Cystic fibrosis (CF)-related diabetes (CFRD) is the most important emerging complication after pulmonary complications. This specific form of diabetes is associated with an increased morbidity and mortality. CFRD prevalence at the age of 10 is 10% and reaches 40 to 50% in adulthood, while a similar percentage is afflicted with milder dysglycemia also called pre-diabetes abnormalities. In order to identify patients at risk and to implement early therapeutic measures, an annual CFRD screening test is recommended for CF patients after 10 years of age. The standard 2-hour oral glucose tolerance test (OGTT) is the recommended screening test. However, this test is perceived by both patients and CF care teams as unpleasant while adding a significant burden and workload, resulting in screening rates lower than 50% in most centers. An ideal alternative test should be simpler, less invasive, more sensitive than an OGTT to establish risks for lung function and/or nutritional deterioration, and predict future CFRD risk. To date, compared to the OGTT, no alternative screening method has demonstrated its effectiveness. However, continuous glucose monitoring (CGM) is emerging as a possible alternative method. In patients living with CF, CGM is easy to use and can identify early dysglycemia, which in turn, can predict increased risk of accelerated decline of pulmonary function and/or weight, higher risk of pseudomonas colonization, and future risk of CFRD. However, these observations are based on studies of small sample size with very limited prospective data. Furthermore, many of the multiple CGM metrics that have been standardized are based on the risk of complications associated with Type 1 and Type 2 Diabetes. Thus, there is a need for prospective studies to identify the CGM metrics and the cut-off level that is relevant as a predictor of clinical deterioration and/or CFRD risk in CF. The identification of such CF-specific criteria would provide important information to target at-risk patients.