For decades, the question facing every newly diagnosed sleep apnea patient has been deceptively simple: which treatment should I try? The answer has been remarkably hard to give, because the three leading options — CPAP machines, oral appliances, and now medication — have never been rigorously compared against each other in a single large trial.
That is about to change. The Patient-Centered Outcomes Research Institute (PCORI) has awarded nearly $14 million to fund a five-year clinical trial that will directly compare all three approaches in 2,400 patients across four major academic medical centers.
The ADAPT-OSA Trial
The study, called ADAPT-OSA, is led by Dr. Sairam Parthasarathy, director of the University of Arizona Center for Sleep, Circadian & Neuroscience Research. Dr. Girardin Jean-Louis, professor of psychiatry and neurology at the University of Miami Miller School of Medicine and director of the Center for Translational Sleep and Circadian Sciences, serves as co-principal investigator.
Participants will be randomly assigned to one of three arms:
- CPAP therapy — the current gold standard, which uses pressurized air to hold the airway open during sleep
- Mandibular advancement device (MAD) — a custom-fitted oral appliance that repositions the lower jaw forward to prevent airway collapse
- Atomoxetine plus oxybutynin — a pharmacological combination that increases upper airway muscle tone during sleep, targeting the neuromuscular mechanism behind airway obstruction
Patients will be followed for 12 months across multiple measures: daytime sleepiness, blood pressure, quality of life, and critically, treatment adherence — the metric that often determines real-world effectiveness more than any laboratory measure of airway control.
Why This Trial Matters
Sleep medicine has operated without definitive comparative data for its core treatments. Previous studies have compared two options at a time, often in small samples, and few have tracked outcomes beyond a few months.
The problem is not a lack of evidence that each treatment works individually. CPAP reduces the apnea-hypopnea index more effectively than any alternative in controlled settings. But adherence is notoriously poor — roughly half of patients abandon the machines within the first year. Oral appliances achieve smaller AHI reductions but are better tolerated, with meta-analyses showing comparable improvements in symptoms and quality of life. The pharmacological option is newer, with the atomoxetine-oxybutynin combination now entering FDA review as part of the AD109 development program.
ADAPT-OSA's design acknowledges what clinicians have long known: the best treatment on paper is not always the best treatment in practice. A therapy that a patient actually uses every night may deliver better outcomes than a theoretically superior one that sits in a drawer.
A Diverse and Representative Study
The trial's enrollment of 2,400 patients across four geographically diverse academic centers is designed to produce results that reflect real clinical populations. Previous OSA treatment studies have been criticized for enrolling predominantly white, male, and middle-aged participants — a demographic that does not represent the broader burden of the disease.
PCORI-funded research specifically emphasizes patient-centered outcomes and comparative effectiveness, meaning the trial is structured to answer the questions patients and their physicians actually face in the clinic, not just the questions that generate publishable endpoints.
The Broader Treatment Landscape
The ADAPT-OSA trial arrives during a period of rapid expansion in sleep apnea treatment options. The FDA approved tirzepatide (Zepbound) for OSA in patients with obesity in late 2024, and Apnimed submitted its new drug application for AD109 in June 2026. Meanwhile, newer hypoglossal nerve stimulation devices like the aura6000 and the Genio system have expanded surgical options.
But more options create more uncertainty. ADAPT-OSA's results, expected in 2031, will provide the evidence base that physicians and patients need to make informed comparative decisions rather than relying on trial-and-error.
What This Means for Patients
Patients currently using CPAP, an oral appliance, or considering medication should not change their treatment based on the announcement of this trial. Results are years away, and the study is designed to inform future clinical guidelines, not to replace current care.
However, patients who have struggled with one treatment option should know that the field is actively working to determine which alternatives may work better for specific patient profiles. The ADAPT-OSA trial represents the most serious effort to date to replace anecdote with evidence in a decision that affects millions of people every night.
Patients interested in participating can monitor enrollment updates through the University of Arizona Center for Sleep, Circadian & Neuroscience Research.
