Short answer: tirzepatide, sold as Zepbound, was studied for sleep apnea in SURMOUNT-OSA, which reported reduced OSA severity and weight in adults with obesity without type 2 diabetes. Retatrutide is investigational and not FDA-approved for anything, but two trials published October 21, 2026 found it lowered breathing interruptions far more than placebo. Neither trial compared the two drugs head to head, so the reports cannot tell you which one works better for you.
How does tirzepatide help sleep apnea?
Sleep apnea happens when your upper airway narrows or blocks during sleep, so your breathing stops and restarts. The NHLBI sleep apnea overview lists obesity among the factors that can narrow your airway. That is one reason a pulmonologist quoted by Medscape calls weight loss an important treatment strategy.
Tirzepatide is a dual GIP/GLP-1 agonist, meaning it activates two hormone receptors. In SURMOUNT-OSA, it reduced sleep apnea severity and weight in adults with obesity who did not have type 2 diabetes, as Medscape’s report on the new trials describes it. Medscape quotes Sanjay R. Patel, MD, a pulmonologist in Pittsburgh who was not involved in the trials, saying the results reinforce weight loss as an important treatment strategy.
For the weight-management side of tirzepatide, read our tirzepatide review.
What is retatrutide, and how is it different?
Retatrutide is an investigational once-weekly injection that activates three hormone receptors: GIP, GLP-1 and glucagon. Tirzepatide activates two of them, GIP and GLP-1. Medical Xpress notes that semaglutide, the active ingredient in Wegovy, targets only one.
| Feature | Retatrutide | Tirzepatide (Zepbound) |
|---|---|---|
| Receptors targeted | GIP, GLP-1 and glucagon (three) | GIP and GLP-1 (two) |
| FDA status | Investigational; not FDA-approved | Studied for sleep apnea in SURMOUNT-OSA |
| Sleep apnea trials | TRIUMPH-1-OSA and TRIUMPH-2-OSA, placebo-controlled, 80 weeks | SURMOUNT-OSA |
| Who was studied | Adults with moderate-to-severe OSA and BMI of 27 or higher, with or without type 2 diabetes | Adults with obesity who did not have type 2 diabetes (per Medscape) |
Who was in the retatrutide sleep apnea trials?
Two phase 3, double-blind, placebo-controlled trials were published in the NEJM trial paper on October 21, 2026, led by Grunstein et al. Eli Lilly funded the studies. Medscape reports that Lilly took part in design, conduct, analysis and manuscript preparation, and that several coauthors are Lilly employees.
TRIUMPH-1-OSA enrolled 243 adults without type 2 diabetes. TRIUMPH-2-OSA enrolled 448 adults with type 2 diabetes. Participants had moderate-to-severe OSA, most of them severe, with baseline averages of 58.6 and 55.9 breathing interruptions per hour. They had a BMI of 27 or higher, and Medical Xpress reports they needed at least 15 breathing pauses per hour to qualify.
Participants received weekly retatrutide or placebo plus lifestyle counseling for 80 weeks. Overnight in-lab sleep studies were done at baseline, week 24 and week 80. The trial registry numbers are NCT05929066 and NCT05929079.
What did the retatrutide trials find?
The main measure was the apnea-hypopnea index, or AHI, which counts the average number of apneas and hypopneas per hour of sleep. Lower numbers mean fewer breathing interruptions. These are the changes at 80 weeks, as the NEJM abstract reports them.
| Trial group | Retatrutide, higher trial doses | Retatrutide, lowest trial dose | Placebo | Difference vs placebo, higher doses |
|---|---|---|---|---|
| Without type 2 diabetes (TRIUMPH-1-OSA) | -34.3 and -31.7 events/hour | -22.9 events/hour | -9.9 events/hour | -24.4 and -21.9 |
| With type 2 diabetes (TRIUMPH-2-OSA) | -24.7 and -25.4 events/hour | -19.2 events/hour | -10.3 events/hour | -14.4 and -15.1 |
The lowest dose showed larger AHI reductions than placebo (-22.9 and -19.2 vs -9.9 and -10.3 events/hour). Medical Xpress reports that at that dose, breathing pauses fell by an average of 23 per hour, with 12.5% average weight loss.
Medscape reports a second measure: the share of people who reached OSA remission (AHI under 5) or mild OSA (AHI 5 to 14) without excessive daytime sleepiness. That combined group is what the figures below count.
| Trial group | Retatrutide: remission or mild OSA without excessive sleepiness | Placebo | Weight loss, retatrutide | Weight loss, placebo |
|---|---|---|---|---|
| Without type 2 diabetes | 51.6% (9 mg arm) | 12.5% | 22.2% (9 mg) and 20.6% (12 mg) | 4.8% |
| With type 2 diabetes | 39.5% | 12.6% | 17.9% and 18.5% | 5.6% |
Medscape also reports that hypoxic burden, a sleep apnea measure of oxygen dips, fell about 63% to 75% at the higher doses, compared with 26% to 30% on placebo. Medscape adds that whether these reductions improve long-term heart outcomes is unknown. Patient-reported sleep impairment improved with the two higher doses in people with type 2 diabetes, but not in people without diabetes.
What are the side effects of retatrutide?
The NEJM abstract says the most common adverse events were gastrointestinal. Medscape lists diarrhea, nausea and constipation, generally mild to moderate.
| Safety finding | What the trials report |
|---|---|
| Most common | Gastrointestinal: diarrhea, nausea, constipation |
| Serious adverse events | 8% in the retatrutide groups in each trial vs 10% on placebo (per Medscape) |
| Pancreatitis | One adjudication-confirmed case with retatrutide |
Ask your prescriber whether these side effects fit your health history before you start any weight-loss drug.
Can retatrutide be prescribed for sleep apnea today?
No. Retatrutide is investigational and not FDA-approved, so it is not a prescription option for sleep apnea today. Medical Xpress reports that, if approved, retatrutide could become another treatment option for sleep apnea in people with obesity, including those with type 2 diabetes.
Can you compare retatrutide and tirzepatide for sleep apnea?
Not directly. Medscape quotes Dr. Patel saying that without head-to-head trials, it is not possible to know whether retatrutide offers advantages over tirzepatide. The two trial programs also enrolled different groups. TRIUMPH-2-OSA included people with type 2 diabetes, while SURMOUNT-OSA enrolled adults without it, and the TRIUMPH trials compared retatrutide only with placebo.
How do these drugs compare with CPAP and other options?
CPAP is the standard treatment for sleep apnea, according to Medical Xpress, and many people find the masks uncomfortable. The NHLBI sleep apnea research page says positive airway pressure therapy is a common and effective treatment, and that many people find it difficult to stick with long-term.
The TRIUMPH trials did not include semaglutide, so they say nothing about how it compares. For a clear picture of how sleep apnea is typically managed, read our guide to understanding sleep apnea.
What can I actually get prescribed for sleep apnea today?
Your realistic options today are the ones your clinician sets up with you:
- A sleep study. The NHLBI says your provider may have you do one to diagnose sleep apnea. Medscape quotes Dr. Patel calling a home sleep test reasonable before deciding next steps.
- CPAP or another breathing device. Breathing devices and lifestyle changes are the common treatments, according to the NHLBI. If they do not work, your provider may recommend surgery.
- An approved weight-loss medicine, with a prescriber. Zepbound (tirzepatide) was studied for sleep apnea in SURMOUNT-OSA. Check the current Zepbound label for its exact listed uses, and ask your prescriber whether it fits you.
- Repeat sleep testing after major weight loss. Medscape quotes Indira Gurubhagavatula, MD, of the University of Pennsylvania, saying substantial weight loss alone does not necessarily mean sleep apnea has resolved, and recommending repeat sleep testing.
Do not stop CPAP without a clinician and a retest. Prices and insurance coverage change, so check the current price and whether your plan covers the product for sleep apnea directly with your prescriber, pharmacy or insurer.
Before you talk to a prescriber
- Ask whether you need a repeat sleep test after you lose weight.
- Ask which sleep apnea treatment fits you: CPAP, another device, surgery or a weight-loss medicine.
- Ask how the gastrointestinal side effects seen in the trials would fit your history.
- Ask your insurer whether your plan covers the product for sleep apnea.
For a clearer picture of the condition itself, start with our sleep apnea overview, then bring your questions to your next appointment.
By MeridianMedicalCentre.com Health Research Team
This article is for general information purposes only and does not constitute medical advice. Consult your doctor or qualified healthcare provider before making changes to your health routine.