A daily weight-loss pill from Eli Lilly cut the number of breathing interruptions in people with obstructive sleep apnea by nearly half over a year in a late-stage trial, the company announced on Monday, Nov. 9. Lilly plans to ask the Food and Drug Administration by the end of 2026 to approve the pill, Foundayo, for the condition.

Lilly already has a sleep apnea drug. Its weekly injection Zepbound became the first medicine the FDA approved for moderate to severe sleep apnea in adults with obesity, in December 2024. Foundayo is a pill, already sold in the U.S. as a weight-loss drug. The new results were presented at the American Heart Association's Scientific Sessions and published in JAMA.

What the trial found

A CPAP mask strapped to a black mannequin head above a silver CPAP machine on a table
A CPAP mask and machine, the standard breathing treatment for sleep apnea, on display in 2012.John Ramspott / Wikimedia Commons.jpg) / CC BY 2.0

The program, called ATTAIN-OSA, ran two studies in adults with moderate to severe sleep apnea and obesity or overweight, one in people who used a CPAP-type breathing machine at night and one in people who did not. Severity is measured by how many times an hour breathing stops or turns shallow during sleep.

After 52 weeksNo breathing machineWith breathing machine
Starting average50.7 events an hour57.6 events an hour
Change on FoundayoDown 21.1 (43.8%)Down 18.3 (27.5%)
Change on placeboDown 4.3 (6.3%)Down 5.5 (3.0%)
Weight lost on Foundayo28.0 lbs (11.5%)28.2 lbs (11.2%)

Among people not using a machine, 31.5% reached remission or mild disease, Lilly said. Systolic blood pressure fell by 8.6 points in that group.

Side effects and what comes next

A tall office tower with red Lilly signs rising above older brick factory buildings and pipes under a clear sky
Eli Lilly's corporate headquarters in Indianapolis in 2011.Paul Sableman / Wikimedia Commons / CC BY 2.0

The most common side effects were nausea, diarrhea, constipation, indigestion and vomiting. Most were mild to moderate. More people quit because of side effects on the pill than on placebo: 12.2% versus 3.8% in the study without machines, and 6.8% versus 0.6% with them.

Sleep apnea is not an approved use for Foundayo yet.

The FDA has not reviewed these results. Lilly says the pill can be taken at any time of day without fasting or water restrictions.