Tirzepatide for Sleep Apnea: The SURMOUNT-OSA Trials, the FDA Indication, and What It Means for Patients With OSA and Obesity

A second disease

Obstructive sleep apnea affects an estimated 30 million American adults, most of them undiagnosed, and obesity is its dominant risk factor: excess tissue around the pharynx narrows the airway, and abdominal fat reduces lung volume and airway stability during sleep. Weight loss has always improved OSA; the problem was that few patients achieved enough of it. SURMOUNT-OSA tested whether tirzepatide's weight loss was enough, and its result made Zepbound the first drug approved for sleep apnea.

The trials

SURMOUNT-OSA was two randomized, double-blind, placebo-controlled 52-week trials, published together in the New England Journal of Medicine in June 2024. Both enrolled adults with obesity (BMI ≥30) and moderate-to-severe OSA (apnea-hypopnea index, AHI, of at least 15 events per hour), without type 1 diabetes. Trial 1 (234 participants) enrolled patients who were not using positive airway pressure (PAP) therapy — because they could not tolerate it or declined it. Trial 2 (235 participants) enrolled patients who were using PAP and continued it. Participants received tirzepatide titrated to 10 or 15 mg weekly or placebo.

Results

AHI. In trial 1, AHI fell by a mean of 25.3 events per hour on tirzepatide versus 5.3 on placebo. In trial 2, by 29.3 versus 5.5. In percentage terms, roughly 50-60% reductions versus about 3-6%. Baseline AHI averaged about 50 events per hour, so a typical patient went from severe OSA to mild.

Remission. The trials defined remission as an AHI below 5, or 5-14 with an Epworth Sleepiness Scale score of 10 or less (mild, non-symptomatic). In trial 1, 43% of tirzepatide patients met the criterion versus 16% on placebo; in trial 2, 51% versus 14%.

Weight. About 18% loss in trial 1 and 20% in trial 2 versus 1-2% on placebo, consistent with SURMOUNT-1.

Other outcomes. Improvements in hypoxic burden (the total oxygen desaturation over the night), sleep-related patient-reported outcomes, systolic blood pressure and high-sensitivity C-reactive protein. Adverse events were the familiar gastrointestinal ones; discontinuation for adverse events was low.

The AHI reduction was larger than weight loss alone would predict from older data, and it exceeded what liraglutide achieved in SCALE Sleep Apnea (about 12 events per hour with 5-6% weight loss). Whether GLP-1/GIP activation improves airway function independently of weight is under study.

What the indication changed

The FDA approved Zepbound for moderate-to-severe OSA in adults with obesity on December 20, 2024. Clinically, that gave sleep physicians a pharmacological option for patients who cannot tolerate PAP — a large group; adherence to CPAP runs around 50%. Financially, it changed coverage. Medicare Part D is barred by statute from covering drugs used for weight loss, but it may cover a drug prescribed for a medically accepted indication. OSA is one. After the approval, Part D plans could cover Zepbound for OSA in obesity, subject to formulary and prior-authorization rules, and many commercial plans that exclude weight-loss drugs cover it under the OSA indication. For a patient with diagnosed OSA and obesity, the OSA indication is often the route to coverage.

Diagnosis is the prerequisite: a sleep study (in-lab polysomnography or home sleep apnea testing) documenting an AHI of 15 or more. Patients who suspect OSA — loud snoring, witnessed pauses, daytime sleepiness, morning headaches, resistant hypertension — should be tested before assuming a GLP-1 will be covered.

Tirzepatide and CPAP

The trials do not show that tirzepatide replaces PAP. Trial 2 patients stayed on PAP. What the results support is a combined strategy: PAP for immediate control, tirzepatide for the underlying obesity, and reassessment by repeat sleep study after substantial weight loss to determine whether PAP can be reduced or stopped. The American Academy of Sleep Medicine's 2025 guidance takes that position. A patient who stops PAP because they feel better, without testing, risks untreated OSA if the response is incomplete.

Because OSA returns with weight regain, the maintenance evidence (SURMOUNT-4) applies: stopping tirzepatide would be expected to bring the AHI back with the weight.

Getting the indication recognized

The sleep-apnea indication matters for coverage as much as for medicine. Medicare Part D, which has long excluded weight-loss drugs, may cover Zepbound for moderate to severe obstructive sleep apnea in adults with obesity because that is a medically accepted indication; a beneficiary with a sleep study documenting the diagnosis and a BMI in range has a coverage route that a beneficiary seeking weight loss alone historically did not. Commercial plans that exclude weight-management drugs sometimes cover the sleep-apnea indication too, and prior-authorization criteria typically require a sleep study with an apnea-hypopnea index in the moderate-to-severe range, a BMI of 30 or higher, and documentation of CPAP use or intolerance. The steps are to obtain or locate the sleep study, ask the plan specifically about Zepbound for obstructive sleep apnea rather than for weight, and have the prescriber submit with the diagnosis code and the study. A patient who has been paying cash for compounded tirzepatide and who has untreated or CPAP-intolerant sleep apnea may find that the approved product is covered at a copay below their current monthly cost, and should check before renewing a compounded plan. The insurance guide covers the wider 2026 coverage picture.

The compounded-product caveat

Everything above concerns Zepbound. Compounded tirzepatide has not been studied for OSA and is not approved for it. A compounded product that delivers the same dose of the same peptide would presumably produce the same physiological effect — that is the premise of using it for weight at all — but the indication, the trial evidence and the insurance coverage belong to the brand product. A patient with OSA who wants coverage needs Zepbound through a prescriber who documents the OSA diagnosis; an insurance-first program such as Ro can manage the prior authorization. A cash-pay patient with OSA choosing compounded tirzepatide for cost should understand that they are extrapolating, and should keep a sleep physician involved. The cheapest tirzepatide guide covers the cost side; the tirzepatide reference covers the full trial program.

Sources

1. Malhotra A, Grunstein RR, Fietze I, et al. Tirzepatide for the treatment of obstructive sleep apnea and obesity (SURMOUNT-OSA). N Engl J Med 2024;391:1193-1205
2. Zepbound prescribing information, OSA indication (December 2024)
3. Centers for Medicare & Medicaid Services, Part D coverage guidance for anti-obesity medications with medically accepted non-weight-loss indications
4. American Academy of Sleep Medicine, clinical guidance on GLP-1 therapy in OSA (2025)
5. Blackman A et al. Effect of liraglutide 3.0 mg in individuals with obesity and moderate or severe obstructive sleep apnea (SCALE Sleep Apnea). Int J Obes 2016;40:1310-1319

Citations are to primary sources (peer-reviewed trials, FDA labeling and announcements, and provider pricing pages). See our sources policy and corrections log.