Lilly said Foundayo reduced apnea-hypopnea index in two Phase 3 trials.
Why it matters: The results extend obesity-drug competition into sleep medicine and suggest a potential oral alternative to injectable therapy. The 52-week trials measured surrogate changes, not fewer cardiovascular events or long-term risk reduction.
- Foundayo reduced apnea-hypopnea index by 13.2 events per hour versus placebo among participants not using positive-airway-pressure therapy.
- The 52-week ATTAIN-OSA program randomized 712 adults across two Phase 3 trials.
- Lilly plans to submit a U.S. FDA application for the sleep-apnea indication by the end of 2026.
- Gastrointestinal adverse events affected 68.0%-70.6% of Foundayo participants, versus 36.6%-37.4% with placebo.
Eli Lilly said on November 9, 2025, that its once-daily oral GLP-1 drug Foundayo, orforglipron, reduced moderate-to-severe obstructive sleep apnea in the two-trial Phase 3 ATTAIN-OSA program. The company plans to seek U.S. approval for adults with obesity or overweight and the condition by the end of 2026. That is a filing plan, not an FDA approval, as described in the announcement and trial presentation.
The randomized, double-blind, placebo-controlled trials ran for 52 weeks. One enrolled adults unable or unwilling to use positive-airway-pressure therapy, a treatment that uses pressurized air to keep the airway open during sleep. The other included people already using it, according to the JAMA publication.
Among participants not using positive airway pressure, the apnea-hypopnea index fell by 17.8 events per hour with Foundayo, compared with 4.5 with placebo - a treatment difference of 13.2. In the positive-airway-pressure group, the declines were 17.3 and 5.3 events per hour, respectively - a difference of 12.0.
Lilly reported that 31.5% of participants not using positive airway pressure reached remission or mild disease. The dossier does not identify that figure as a prespecified endpoint or provide a comparator percentage. Foundayo also improved weight, measures of low blood oxygen during sleep, high-sensitivity C-reactive protein and systolic blood pressure. The announcement, presentation and JAMA publication were dated November 9, 2025.
Safety remains a consideration. Gastrointestinal adverse events occurred in 68.0%-70.6% of Foundayo participants across the two trials, compared with 36.6%-37.4% with placebo. Treatment discontinuation because of adverse events ranged from 6.8% to 12.2%. The JAMA publication identifies Lilly as the funder and sponsor of the trials.
Lilly already has an FDA-approved sleep-apnea treatment: injectable Zepbound, approved in December 2024 for adults with obesity and moderate-to-severe obstructive sleep apnea. Foundayo would be an oral option, subject to review. The FDA approval was not based on a head-to-head comparison with Foundayo.
By the numbers
- 13.2 events per hour - treatment difference in apnea-hypopnea index among participants not using positive airway pressure
- 12.0 events per hour - treatment difference among participants using positive-airway-pressure therapy
- 712 adults - randomized across the two 52-week Phase 3 trials
Yes, but: The trials showed changes in apnea-hypopnea index and related measures, but did not establish fewer cardiovascular events or long-term reductions in cardiometabolic risk.
What's next: Lilly plans to submit a U.S. FDA application for Foundayo in sleep apnea by the end of 2026.