Eli Lilly could soon see two label expansions for Foundayo, it’s oral GLP-1, in swift succession: In September, the drugmaker filed for U.S. review in Type 2 diabetes. And now, with new phase 3 data in hand, Lilly plans to approach the FDA about an application for obstructive sleep apnea (OSA).
Backing the potential OSA label expansion is Lilly’s two-study, phase 3 Attain-OSA trial, presented Monday at the American Heart Association (AHA) Scientific Sessions 2026 and published in JAMA. At 52 weeks, the collective 712-patient program met its primary endpoint, with Foundayo (orforglipron) significantly reducing sleep apnea severity as measured using the standard apnea-hypopnea index (AHI) disease rating scale.
The Indianapolis-based drugmaker estimates that 936 million adults globally are impacted by sleep apnea. The condition causes a patient’s airway to repeatedly collapse during sleep, leading to drops in oxygen and spikes in blood pressure that are linked to hypertension, heart failure, and atrial fibrillation, among others cardiac conditions. OSA is also more common in patients with obesity—Foundayo’s inaugural indication—and can worsen obesity by increasing weight gain.
Attain-OSA tested Foundayo in patients with OSA as well as overweight or obesity, split across two studies consisting of patients who also used positive air pressure (PAP) therapy (349) and those who were unable or unwilling to (363). PAP therapy is the gold standard in OSA treatment, but because it involves a bedside machine and sleeping with a mask on, many patients find the approach unsustainable.
At baseline, the patients who didn’t use PAP had an average of 50.7 AHI events per hour. After 52 weeks, Foundayo reduced these episodes by 21.1 per hour, or 43.8%, compared to a reduction of 4.3 events per hour with placebo. Importantly, 47.2%, or nearly half of non-PAP patients on Foundayo reduced their nightly AHI events by 50% or more. And 31.5% attained remission or mild disease, measured as 5 to under 15 AHI events per hour.
Among the patients who did use PAP, Foundayo reduced AHI events by 18.3 per hour, a 27.5% reduction from an average baseline of 57.6 events per hour. More than one third reduced their AHI by 50% or more and one-fifth achieved remission or mild disease.
Foundayo also reduced sleep apnea-specific hypoxic burden, a measure of the how long and how deeply oxygen levels fall during sleep. The reduction worked out to 55.9% on Foundayo in the non-PAP group and 45.8% in those who were receiving PAP therapy.
On top of the sleep benefits, patients taking Foundayo improved their weight and cardiovascular risk factors. Both patient groups taking Foundayo reduced their bodyweight by roughly 11% which amounted to an average of 28 and 28.2 pounds in the non-PAP and PAP groups, respectively.
And in terms of cardiac risk, patients on Foundayo reduced their hsCRP, a marker of inflammation linked to cardiac health, by 48.9% in the non-PAP group and 38.6% in patients that used PAP. Foundayo also led to 8.6 mmHg and 7.3 mmHg reductions in systolic blood pressure in the respective PAP cohorts.
“OSA is one of the most serious complications of obesity and is closely linked to cardiovascular disease,” Thomas Seck, M.D., senior vice president of product development of Lilly Cardiometabolic, said in a statement. “In ATTAIN-OSA, Foundayo significantly improved sleep apnea along with key cardiovascular risk factors, showing its potential to treat conditions that drive heart disease.”
Seck added that Lilly has plans to submit the phase 3 data to the FDA by the end of the year.
The drug’s safety profile in Attain-OSA was on par with past Foundayo trials. Gastrointestinal issues were the most common adverse events. Discontinuation rates were 12.2% in the Foundayo group, compared to 3.8% with placebo for patients not using PAP. Among patients using PAP, discontinuation rates were 6.8% in the Foundayo group versus 0.6% on placebo.
Lilly’s injectable GLP-1, Zepbound, was the first medication the FDA approved specifically to treat moderate to severe OSA. Other approved treatment focus on treating symptoms of the condition, like daytime sleepiness, rather than the obstructed airways and loss of oxygen that happen at night.
Foundayo is in the running to become the first oral treatment for the condition. However, Apnimed’s AD109, a non-GLP-1 oral treatment designed to prevent airway collapse during sleep, could get there first. The biotech reported a phase 3 win for AD109 over the summer and has a February 2027 PDUFA date locked in with the FDA.
Lilly reported $184 million in sales for Foundayo in Q3. The sales figures were up significantly from $98 million in Q2 but still missed Wall Street expectations of $217 million. For context, Foundayo’s rival—Novo's Wegovy pill—posted $811 million in Q3, giving it a sizeable lead in the oral obesity market. An approval in OSA could give Lilly’s pill some added momentum to close that gap.
Wegovy pill snagged FDA approval for weight management and cardiovascular risk reduction last December, giving it a three month lead and an extra indication over Foundayo which was approved April 1 for weight management, alone. In October, Foundayo won a recommendation in weight management and Type 2 diabetes from the European Medicines Agency, and now awaits a final signoff from the European Commission. On the diabetes front, Novo markets it's Ozempic pill, a separate lower-dose, semaglutide-based oral drug approved to treat diabetes in the U.S. and the EU.
Lilly is also aiming for an OSA approval with its next-gen obesity drug, retatrutide. The triple-G candidate has set a new bar for weight loss medications, allowing more than one-third of patients to lose at least 25% of their body weight.
In data published at a medical meeting this summer and the New England Journal of Medicine last month, the drug reduced AHI events by as much as 60% (36.1 events) per hour while also significantly reducing body weight and arthritic knee pain. Retatrutide is expected to meet a timely approval in the first quarter of next year.