Eli Lilly's obesity pill Foundayo (orforglipron) has delivered promising results in a major clinical trial, significantly reducing the severity of obstructive sleep apnoea (OSA) in adults with obesity or overweight, potentially expanding the drug's role beyond weight management.
Results from the Phase 3 ATTAIN-OSA programme showed that Foundayo reduced sleep-related breathing interruptions by an average of up to 43.8% over 52 weeks. The drug also reduced the severity and duration of oxygen drops during sleep by as much as 55.9%.
In a particularly notable finding, 31.5% of participants taking Foundayo who were not using positive airway pressure (PAP) therapy achieved either remission or mild sleep apnoea by the end of the trial.
The results could strengthen the case for treating obesity-related sleep apnoea through therapies that address weight and associated metabolic risks, rather than focusing exclusively on breathing support during sleep.
The 52-week trial evaluated Foundayo in adults with moderate-to-severe obstructive sleep apnoea and obesity or overweight, both with and without PAP therapy.
Among participants not using PAP therapy, Foundayo reduced the average number of breathing interruptions from 50.7 to 29.6 events per hour, representing a 43.8% reduction. The placebo group recorded a reduction of just 6.3%.
In this group, 47.2% of participants taking Foundayo achieved at least a 50% reduction in breathing interruptions, while 31.5% reached remission or mild disease.
Among participants continuing PAP therapy, Foundayo reduced breathing interruptions by 27.5%, compared with a 3% reduction in the placebo group. Nearly 20% of participants taking the drug achieved remission or mild disease.
The drug also delivered substantial improvements in sleep-related oxygen deprivation, measured through sleep apnoea-specific hypoxic burden.
This measure captures not just how frequently breathing is interrupted, but also how deeply and for how long oxygen levels fall during sleep. Foundayo reduced hypoxic burden by 55.9% in participants not using PAP therapy and 45.8% in those using it.
The sleep apnoea improvements were accompanied by significant weight loss and improvements in certain cardiovascular risk factors.
Participants taking Foundayo lost an average of 28 pounds (11.5%) without PAP therapy and 28.2 pounds (11.2%) with PAP therapy over 52 weeks.
The drug also reduced high-sensitivity C-reactive protein (hsCRP), a marker of inflammation, by 48.9% and 38.6%, respectively.
Systolic blood pressure fell by an average of 8.6 mmHg among participants not using PAP therapy and 7.3 mmHg among those using it.
Vaishnavi Kundel, MAssociate Professor of Medicine, Division of Pulmonary, Critical Care and Sleep Medicine, Icahn School of Medicine at Mount Sinai: "We know there's a two-way relationship between sleep and cardiovascular health, and the repeated drops in oxygen that happen with obstructive sleep apnea can strain blood pressure and the heart over time.
"In ATTAIN-OSA, Foundayo significantly reduced breathing interruptions and drops in oxygen during sleep, while also improving blood pressure and inflammation. In addition to improving their sleep, what I care about for my patients is improving the cardiovascular risk factors that have the potential to impact long-term health."
OSA is increasingly recognised as a major cardiovascular health concern. The condition causes repeated airway collapses during sleep, resulting in oxygen deprivation and spikes in blood pressure. It has been associated with hypertension, heart failure, atrial fibrillation, coronary artery disease and stroke.
Lilly is now preparing to take the findings to regulators, with plans to submit Foundayo to the US Food and Drug Administration by the end of 2026 for the treatment of moderate-to-severe obstructive sleep apnoea in adults with obesity or overweight.
Thomas Seck, Senior Vice President of Product Development of Lilly Cardiometabolic Health: "OSA is one of the most serious complications of obesity and is closely linked to cardiovascular disease. In ATTAIN-OSA, Foundayo significantly improved sleep apnea along with key cardiovascular risk factors, showing its potential to treat conditions that drive heart disease.
"Foundayo is already making a difference for people living with obesity, and 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."
Foundayo is a once-daily oral GLP-1 receptor agonist that can be taken at any time of the day without restrictions on food or water intake. Its oral formulation could offer an alternative to injectable obesity medicines for patients who prefer a pill.
