Eli Lilly's Foundayo pill cuts sleep apnea events in late-stage trial

Patients who took Foundayo without using a PAP breathing machine logged 21.1 fewer apnea-hypopnea index events per hour at 52 weeks, against a 4.8 per hour drop on placebo, Lilly said. Their overall AHI fell 43.8%, compared with 6.3% for placebo. Just under a third of them — 31.5% — hit remission or improved to mild OSA.

In the second study, patients already on PAP therapy who added Foundayo saw 18.3 fewer AHI events per hour versus 5.5 for placebo, with an overall AHI reduction of 27.5% against 3%. About 19.6% of that group reached remission or mild OSA. The pill also cut sleep apnea-specific hypoxic burden by 55.9% without PAP and 45.8% with it, while patients shed roughly 11% of their weight and saw an inflammation marker drop.

The first trial enrolled 363 people unable or unwilling to use PAP therapy; the second took in 349 who had been on PAP for at least three months and stayed on it during the study. Doses started low and climbed every four weeks to different maximums.

Side effects were mostly gastrointestinal — nausea, diarrhea, constipation and vomiting — and generally mild to moderate, matching other GLP-1 drugs. Around 12% of non-PAP patients on Foundayo quit over side effects, versus 3.8% on placebo. In the PAP group, 6.8% discontinued the drug, compared with 0.6% on placebo.

Lilly said it will file for U.S. approval of Foundayo for moderate-to-severe OSA in adults who are obese or overweight by the end of the year. The pill launched in the U.S. in April, and Zepbound became the first medication cleared for OSA in December 2024. Dr. Thomas Seck, a Lilly senior vice president, said the filing could open the door to helping people living with the condition.

OSA strikes when narrowed or blocked airways interrupt breathing during sleep, dropping oxygen and raising blood pressure in ways tied to hypertension, heart failure and stroke. It affects nearly 1 billion adults worldwide, including 80 million Americans ages 20 and up, according to the National Council on Aging. Lilly says most have never been diagnosed.