SURMOUNT-OSA

SURMOUNT-OSA is the pair of trials that made tirzepatide the first drug approved for obstructive sleep apnea. Published in 2024, it ran two parallel 52-week studies in adults with moderate-to-severe sleep apnea and obesity: one in people not using a CPAP machine, one in people who were. Participants received the maximum tolerated dose of tirzepatide, 10 mg or 15 mg, or placebo.

The measure was the apnea-hypopnea index, or AHI — how many times an hour breathing stops or becomes shallow during sleep. Baseline was severe: a mean of 51.5 events per hour in the first trial and 49.5 in the second. At 52 weeks, AHI fell by 25.3 events per hour on tirzepatide versus 5.3 on placebo in the non-CPAP trial, and by 29.3 versus 5.5 in the CPAP trial. Hypoxic burden, inflammation as measured by hsCRP, systolic blood pressure and patient-reported sleep quality all improved as well.

Cutting roughly 25 events an hour from a starting point near 50 moves many people from severe to mild territory. It rarely reaches zero, and that distinction matters — these trials did not show that tirzepatide replaces CPAP, and the CPAP arm continued using their machines throughout.

The practical upside is often financial. Zepbound’s sleep-apnea indication is a separate labeled use, and plans that refuse to cover weight-loss drugs sometimes cover a sleep-apnea diagnosis. A documented sleep study becomes a coverage asset. Note that the label specifies 10 mg or 15 mg for this indication — 5 mg is not enough.

Ask a clinician whether a sleep study is warranted if you have never had one, whether your existing study is recent enough to support a claim, and when your apnea should be re-measured on treatment. Our SURMOUNT-OSA breakdown and Zepbound sleep-apnea guide cover the coverage angle.