Foundayo sleep apnea data from the Phase 3 ATTAIN-OSA program show that Eli Lilly and Company’s once-daily oral GLP-1 pill, Foundayo (orforglipron), significantly reduced obstructive sleep apnea (OSA) severity in adults with obesity or overweight, Lilly announced on November 9, 2026. At 52 weeks, Foundayo met the primary endpoint of lowering the apnea-hypopnea index (AHI), the standard measure of sleep apnea severity, while also improving body weight and several cardiovascular risk factors.
The results were presented at the American Heart Association (AHA) Scientific Sessions 2026 and published simultaneously in JAMA. In adults with moderate-to-severe OSA and obesity or overweight, Foundayo reduced breathing interruptions during sleep by up to an average of 44%, and up to 32% of participants reached remission or mild disease. Lilly also reported that Foundayo lowered sleep apnea-specific hypoxic burden by up to an average of 55.9%, which reflects improved oxygen levels during sleep.
Lilly, the maker of Zepbound (tirzepatide), plans to submit Foundayo to the U.S. Food and Drug Administration (FDA) for moderate-to-severe OSA in adults with obesity or overweight by the end of 2026, with other global submissions to follow. That is a forward-looking plan and remains subject to regulatory review. For readers following the Foundayo (orforglipron) drug profile, the Foundayo sleep apnea readout adds a new potential indication beyond weight management.
Foundayo Sleep Apnea Trial Design: How ATTAIN-OSA Was Built
ATTAIN-OSA (NCT06649045) is a Phase 3, 52-week, randomized, multicenter, double-blind, placebo-controlled trial. It tested Foundayo at the maximum tolerated dose (MTD) once daily against placebo in people with moderate-to-severe OSA and obesity or overweight. The program contained two pivotal, independent studies, and all efficacy figures in the announcement represent the efficacy estimand.
Study 1 enrolled 363 participants who were unable or unwilling to use positive airway pressure (PAP) therapy. Study 2 enrolled 349 participants who had used PAP for at least three months at screening and continued it throughout the study. This split lets the Foundayo sleep apnea results be read separately for people with and without PAP, which matters because the two groups started from different baseline AHI levels.
Participants on Foundayo began at 0.8 mg once daily and moved up in stepwise increases at four-week intervals to an MTD of 9 mg, 14.5 mg or 17.2 mg. Lilly noted that the studies used an investigational formulation at dosages equivalent to Foundayo tablets. Foundayo is a once-daily oral small molecule that can be taken at any time of day without food or water restrictions, according to the company.
| ATTAIN-OSA Design Element | Detail (per Lilly release) |
|---|---|
| Sponsor | Eli Lilly and Company (NYSE: LLY) |
| Registry identifier | NCT06649045 |
| Phase and duration | Phase 3, 52 weeks |
| Design | Randomized, multicenter, double-blind, placebo-controlled |
| Intervention | Foundayo (orforglipron) MTD once daily vs. placebo |
| Study 1 population | 363 participants not using PAP therapy |
| Study 2 population | 349 participants using PAP therapy for at least 3 months |
| Starting dose | 0.8 mg once daily |
| Titration | Stepwise every 4 weeks to MTD of 9 mg, 14.5 mg or 17.2 mg |
| Presentation and publication | AHA Scientific Sessions 2026; JAMA |
Foundayo Sleep Apnea Efficacy: AHI, Hypoxic Burden, Weight and Cardiovascular Markers
OSA affects an estimated 936 million adults worldwide, and most have never been diagnosed, according to Lilly’s citation of a 2019 Lancet Respiratory Medicine analysis. In OSA, the airway repeatedly collapses during sleep, causing drops in oxygen and rises in blood pressure that are associated with hypertension, heart failure, atrial fibrillation, coronary artery disease and stroke. The AHA counts healthy sleep among its Life’s Essential 8 measures and recommends OSA screening in people with certain cardiovascular conditions.
Among participants not using PAP therapy, Foundayo reduced AHI by 21.1 events per hour (43.8%) at 52 weeks from an average baseline of 50.7 events per hour, versus 4.3 events per hour with placebo. In this group, 47.2% achieved an AHI reduction of 50% or more, and 31.5% reached remission or mild disease. Remission was defined as AHI below 5 events per hour, and mild OSA as AHI from 5 to under 15 with an Epworth Sleepiness Scale score of 10 or less.
Among participants using PAP therapy, Foundayo reduced AHI by 18.3 events per hour (27.5%) from an average baseline of 57.6, versus 5.5 events per hour with placebo. There, 33.7% achieved a 50% or greater AHI reduction and 19.6% reached remission or mild disease. These Foundayo sleep apnea outcomes show benefit on top of PAP, although the absolute effect was smaller than in the group without PAP.
| ATTAIN-OSA Primary and Key Secondary Endpoints (Efficacy Estimand) | Study 1: Foundayo (No PAP) | Study 1: Placebo | Study 2: Foundayo (With PAP) | Study 2: Placebo |
|---|---|---|---|---|
| Change in AHI, events per hour | -21.1 | -4.3 | -18.3 | -5.5 |
| Baseline average AHI, events per hour | 50.7 | 50.7 | 57.6 | 57.6 |
| Percent change in AHI | -43.8% | -6.3% | -27.5% | -3.0% |
| Change in hypoxic burden, percent-minutes per hour | -81.4 (-55.9%) | -26.7 (-18.3%) | -75.0 (-45.8%) | -27.9 (-17.0%) |
| Percent change in body weight | -11.5% (-28.0 lbs) | -1.8% (-4.4 lbs) | -11.2% (-28.2 lbs) | -0.9% (-2.2 lbs) |
Hypoxic burden measures how deeply and for how long oxygen levels fall during sleep, so it adds information that AHI alone does not capture. Foundayo cut it by 81.4 percent-minutes per hour (55.9%) without PAP and 75.0 percent-minutes per hour (45.8%) with PAP. Participants lost an average of 28.0 lbs (11.5%) without PAP and 28.2 lbs (11.2%) with PAP, and hsCRP, a marker of inflammation, fell by 48.9% and 38.6%.
Systolic blood pressure dropped by an average of 8.6 mmHg without PAP and 7.3 mmHg with PAP. Lilly noted that all measures except systolic blood pressure were controlled for family-wise type 1 error. In practical terms, the Foundayo sleep apnea data connect airway and oxygen improvements to cardiometabolic markers, though the trial was designed primarily to assess OSA rather than cardiovascular outcomes.
| Cardiometabolic Marker | Foundayo (No PAP) | Foundayo (With PAP) |
|---|---|---|
| Average weight loss | 28.0 lbs (11.5%) | 28.2 lbs (11.2%) |
| hsCRP reduction (average) | 48.9% | 38.6% |
| Systolic blood pressure reduction (average) | 8.6 mmHg | 7.3 mmHg |
| AHI reduction of 50% or more | 47.2% of participants | 33.7% of participants |
| Remission or mild OSA | 31.5% of participants | 19.6% of participants |
Foundayo Sleep Apnea Safety Profile and Expert Perspectives from Lilly and Mount Sinai
Lilly said the overall safety and tolerability profile was generally consistent with earlier trials in the ACHIEVE and ATTAIN programs. The most common adverse events were gastrointestinal, including nausea, diarrhea, constipation, dyspepsia and vomiting, and were generally mild to moderate. Discontinuation due to adverse events with Foundayo versus placebo was 12.2% versus 3.8% without PAP and 6.8% versus 0.6% with PAP.
Vaishnavi Kundel, M.D., M.S., Associate Professor of Medicine at the Icahn School of Medicine at Mount Sinai, pointed to a “two-way relationship” between sleep and cardiovascular health. She said the Foundayo sleep apnea results showed fewer breathing interruptions and oxygen drops along with better blood pressure and inflammation, and that improving cardiovascular risk factors matters for her patients’ long-term health.
Thomas Seck, M.D., Senior Vice President of Product Development at Lilly Cardiometabolic Health, described OSA as one of the most serious complications of obesity and closely linked to cardiovascular disease. He said the data show Foundayo’s potential to treat conditions that drive heart disease, and he tied the FDA submission plan to the end of this year. Patients should review the full prescribing information and report side effects through FDA MedWatch.
| Safety Measure | Foundayo (No PAP) | Placebo (No PAP) | Foundayo (With PAP) | Placebo (With PAP) |
|---|---|---|---|---|
| Discontinuation due to adverse events | 12.2% | 3.8% | 6.8% | 0.6% |
| Most common adverse events | Nausea, diarrhea, constipation, dyspepsia, vomiting (generally mild to moderate) | Not disclosed | Same gastrointestinal pattern | Not disclosed |
