Eli Lilly’s Foundayo Pill Cuts Sleep Apnea Episodes by Up to 44% in Late-Stage Trial
Eli Lilly said Monday that its once-daily weight-loss pill Foundayo significantly reduced the severity of obstructive sleep apnea in adults with obesity, meeting the main goal of a late-stage clinical trial and opening the door to a new use for the drug. The company plans to ask the U.S. Food and Drug Administration to approve Foundayo for moderate-to-severe sleep apnea by the end of 2026.
The results, from the Phase 3 ATTAIN-OSA program, were presented Monday at the American Heart Association Scientific Sessions in Chicago and published simultaneously in the medical journal JAMA. In the 712-patient program, Foundayo cut breathing interruptions by up to 44% over 52 weeks, while also helping patients lose about 28 pounds on average.
What the Trial Found
ATTAIN-OSA was a 52-week, randomized, double-blind, placebo-controlled program that tested Foundayo, known generically as orforglipron, against a placebo in adults with moderate-to-severe obstructive sleep apnea who also had obesity or were overweight. It was run as two parallel studies.
The first study enrolled 363 people who were unable or unwilling to use positive airway pressure, or PAP, therapy — the mask-and-machine treatment that is the standard approach to sleep apnea. In that group, Foundayo reduced the apnea-hypopnea index, or AHI, the standard measure of how many times per hour a sleeper’s breathing stops or becomes shallow, by 43.8%, compared with a 6.3% reduction on placebo. Patients taking the pill averaged 21.1 fewer breathing interruptions per hour, against 4.8 fewer for those on placebo.
The second study enrolled 349 people who had been using PAP therapy for at least three months and continued it during the trial. There, Foundayo reduced AHI by 27.5%, compared with 3% on placebo, with patients averaging 18.3 fewer events per hour against 5.5 fewer on placebo.
Foundayo also improved a measure called sleep apnea-specific hypoxic burden, which tracks how deeply and how long blood oxygen levels fall during sleep. That measure fell by 55.9% in people not using PAP therapy and by 45.8% in those using it.
Nearly a third of the patients who took Foundayo without PAP therapy — 31.5% — reached remission or improved to mild sleep apnea by the end of the year. In the group that combined the pill with PAP therapy, 19.6% reached remission or mild disease.
“With plans to submit these results to the FDA by the end of the year, we could have the opportunity to help people living with OSA,” said Dr. Thomas Seck, senior vice president of product development for Lilly Cardiometabolic Health.
A Pill Instead of a Machine
Obstructive sleep apnea is the most common sleep-related breathing disorder. During sleep, the airway repeatedly narrows or closes, cutting off breathing for seconds at a time. Left untreated, it is linked to high blood pressure, heart disease, stroke, and daytime fatigue. The standard treatment, PAP therapy, blows air through a mask to keep the airway open — but many people find the machines uncomfortable, noisy, or hard to use consistently, and a large share of patients stop using them.
That gap is why drugmakers have been racing to develop medicines for the condition. Lilly’s injectable drug Zepbound became the first medication the FDA approved specifically to treat moderate-to-severe sleep apnea, in December 2024. Foundayo would be the first once-daily pill for the condition if the FDA approves it for that use, offering a needle-free option for people who cannot or will not use a machine or an injection.
Foundayo belongs to the GLP-1 class of drugs, the same family as Zepbound and Novo Nordisk’s Wegovy. It won U.S. approval for weight management earlier this year and launched in April. The company also filed in September for U.S. review of the pill in Type 2 diabetes. In the ATTAIN-OSA program, patients on Foundayo lost roughly 11% of their body weight over 52 weeks, alongside the improvement in their breathing.
The results were largely expected by Wall Street, Citi analyst Geoff Meacham said, after Zepbound’s earlier success in sleep apnea. But the size of the effect — and the fact that it held up both with and without PAP therapy — gives Lilly a strong case for an expanded label.
Why This Matters
For patients, the appeal is straightforward. A daily pill is far easier to stick with than a mask worn every night, and it treats the weight that often drives the condition at the same time. For Lilly, a sleep apnea approval would extend the market for Foundayo well beyond weight loss, in a category where its main rival, Novo Nordisk, has no approved pill.
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The timing also matters for the broader GLP-1 market. The FDA recently ordered a new safety warning on GLP-1 drugs after reports of a rare eye condition, a reminder that the fast-growing class is under close regulatory scrutiny. Positive trial data in a new indication helps Lilly argue that the benefits of its drugs extend well beyond the scale.
Cost and coverage will be the next question. GLP-1 drugs are expensive, and insurers have been selective about which uses they pay for. Whether health plans cover Foundayo for sleep apnea — and at what price — will determine how many patients can actually get it. Those decisions will not come until after the FDA reviews the application, and household budgets are already under pressure from rising prices, as the latest inflation data will show.
What the Results Do Not Show
The trial was a success on its main measures, but the results are not a cure. An editorial accompanying the JAMA publication noted that a substantial proportion of participants still had moderate-to-severe sleep apnea at the end of the 52 weeks, even after their breathing improved markedly. A 44% reduction in breathing interruptions is a major improvement, but for many patients it does not eliminate the condition.
That nuance matters for how the drug will be used. For some patients, Foundayo could replace PAP therapy. For others, it is more likely to be used alongside it, as in the second study, where the combination produced the largest absolute gains. Doctors will also want to see the full safety data in the JAMA publication before weighing the pill against existing treatments.
What Happens Next
Lilly said it plans to submit the ATTAIN-OSA results to the FDA for moderate-to-severe obstructive sleep apnea in adults with obesity or overweight by the end of 2026, with submissions in other countries to follow. The agency will then decide whether to approve the new use, a process that typically takes several months.
If approved, Foundayo would join Zepbound as the second Lilly drug cleared for sleep apnea — and the first in a pill. For the millions of Americans who struggle with a breathing machine every night, that would be a meaningful new option.
Frequently Asked Questions
What is Foundayo?
Foundayo is the brand name for orforglipron, a once-daily oral GLP-1 drug made by Eli Lilly. It was approved in the United States for weight management earlier this year. It is not yet approved for sleep apnea.
How much did Foundayo reduce sleep apnea in the trial?
In the ATTAIN-OSA Phase 3 program, Foundayo cut breathing interruptions by 43.8% in patients not using PAP therapy and by 27.5% in patients who continued PAP therapy, over 52 weeks. It also reduced oxygen deprivation during sleep by up to 55.9%.
When could Foundayo be approved for sleep apnea?
Eli Lilly plans to submit the trial results to the FDA by the end of 2026. The agency would then review the application, a process that typically takes several months. There is no guarantee of approval.
Does Foundayo cure sleep apnea?
No. The trial showed a large reduction in the severity of sleep apnea, and about a third of patients not using PAP therapy reached remission or mild disease. But many participants still had moderate-to-severe sleep apnea at the end of the study, according to an editorial in JAMA.
Sources
- Eli Lilly and Company press release, “Lilly’s Foundayo (orforglipron) significantly reduced obstructive sleep apnea severity,” PR Newswire, November 9, 2026: https://www.prnewswire.com/news-releases/lillys-foundayo-orforglipron-significantly-reduced-obstructive-sleep-apnea-severity-reinforcing-its-potential-to-improve-health-beyond-weight-loss-302932877.html
- Reuters, “Lilly’s weight-loss pill improves sleep apnea in late-stage trial,” November 9, 2026: https://mymixfm.com/2026/11/09/lillys-weight-loss-pill-meets-main-goal-in-late-stage-sleep-apnea-study/
- CNBC, “Eli Lilly Foundayo pill cuts sleep apnea severity,” November 9, 2026: https://www.europesays.com/ie/774180/
- Fierce Pharma, “Lilly eyes filing after Foundayo scores ph. 3 win in sleep apnea,” November 9, 2026: https://www.fiercepharma.com/pharma/lilly-heads-fda-phase-3-foundayo-win-sleep-apnea
