Trial review

SURMOUNT-OSA and The drug for Sleep Apnea

This medicine in obstructive sleep apnoea with obesity

Dr. Parmis, Editorial Lead · Jonathan Michael Snipes, MD, Medical Reviewer

Published 2026-08-03Updated 2026-08-03Sources captured 2026-08-03Medically reviewed not yet — why

Direct answer

SURMOUNT-OSA was a two phase 3, randomised, double-blind, placebo-controlled trials under one master protocol funded by Eli Lilly and Company. The active ingredient reduced the apnoea-hypopnoea index, body weight, hypoxic burden, hsCRP and systolic blood pressure, and improved sleep-related patient-reported outcomes.

Answer last reviewed: 2026-08-03Evidence:

SURMOUNT-OSA at a glanceVerified

Data table
Design	Two phase 3, randomised, double-blind, placebo-controlled trials under one master protocol
Population	Adults with moderate-to-severe obstructive sleep apnoea and obesity. Trial 1 enrolled participants not using positive airway pressure; trial 2 enrolled participants using PAP at baseline
Sample size	not captured
Intervention	The molecule once weekly at maximum tolerated dose
Comparator	Placebo
Duration	52 weeks
Primary endpoint	Change in apnoea-hypopnoea index from baseline
Main result	This GLP-1 reduced the apnoea-hypopnoea index, body weight, hypoxic burden, hsCRP and systolic blood pressure, and improved sleep-related patient-reported outcomes

NCT NCT05412004 · DOI 10.1056/NEJMoa2404881 · PMID 38912654Last source check: 2026-08-03

How to read SURMOUNT-OSA without over-reading it

Show this figure as a table

Data table
Step	Stage	What happens
1	Who was eligible	Adults with moderate-to-severe obstructive sleep apnoea and obesity. Trial 1 enrolled participants not using positive airway pressure; trial 2 enrolled participants using PAP at baseline
2	What they received	Tirzepatide once weekly at maximum tolerated dose
3	What it was compared against	Placebo
4	For how long	52 weeks
5	What was measured first	Change in apnoea-hypopnoea index from baseline
6	What the group average was	Tirzepatide reduced the apnoea-hypopnoea index, body weight, hypoxic burden, hsCRP and systolic blood pressure, and improved sleep-related patient-reported outcomes
7	What it does not tell you	A group average is not a prediction for any individual reader.

Strip any step and the result stops meaning what the trial found.

What the label says about safety

Tirzepatide carries a boxed warning for thyroid C-cell tumours observed in rats. Whether it causes them in humans has not been determined. It is contraindicated in anyone with a personal or family history of medullary thyroid carcinoma, in Multiple Endocrine Neoplasia syndrome type 2, and in known serious hypersensitivity to tirzepatide or its excipients — anaphylaxis and angioedema have been reported.

One line in the label is directly relevant to this market: coadministration with other tirzepatide-containing products, or with any GLP-1 receptor agonist, is not recommended. A patient using a compounded preparation alongside a branded product, or alongside another GLP-1, is doing something the label advises against.

Acute gallbladder disease and pancreatitis have been reported. Severe abdominal pain radiating to the back warrants urgent assessment, not a message to a chat widget. Read the full prescribing information and discuss it with a clinician.

Primary results, from the peer-reviewed publicationNew England Journal of Medicine 2024;391(13)

Show this figure as a table

Data table
Item	Weight change	Evidence
Intervention group	not captured	—
Comparator group	not captured	—

Bars fill only from the peer-reviewed publication. Topline and press-release figures are labelled as such and are never charted as results.

What this trial can and cannot tell you

What this trial can and cannot tell you
Question	Position
Average effect in the studied population	Reported once captured
Your individual outcome	Not predicted by any trial
Effect of a compounded preparation	Not studied here
Effect at doses outside the protocol	Not studied here
Effect after stopping	Only if the trial included a withdrawal phase
Long-term safety beyond the trial	Outside the observation window

Who was studied?

Adults with moderate-to-severe obstructive sleep apnoea and obesity. Trial 1 enrolled participants not using positive airway pressure; trial 2 enrolled participants using PAP at baseline

Registry and publication identifiers: NCT05412004 · DOI 10.1056/NEJMoa2404881 · PMID 38912654. Sponsor: Eli Lilly and Company. Checked against the source on 2026-08-03.

What was given, and what was it compared against?

Design, intervention and comparator
Field	What the record states
Design	Two phase 3, randomised, double-blind, placebo-controlled trials under one master protocol
Intervention	Tirzepatide once weekly at maximum tolerated dose
Dose	10 mg or 15 mg
Comparator	Placebo
Duration	52 weeks
Primary endpoint	Change in apnoea-hypopnoea index from baseline

A placebo comparator is what allows a trial to claim the drug caused the difference. An active comparator answers a weaker question — whether the drug is at least as good as one already shown to work — and the two are routinely reported in the same words.

What did it find?

Tirzepatide reduced the apnoea-hypopnoea index, body weight, hypoxic burden, hsCRP and systolic blood pressure, and improved sleep-related patient-reported outcomes

A trial result is a mean across a population, not a prediction for an individual. The same trial that produces an average contains people who did far better and people who did not respond, and a page quoting only the average is quoting the part that flatters it.

What were the adverse events and discontinuations?

Adverse events are reported in the primary publication.

What are the limitations?

Industry-funded. PAP was withdrawn before assessment in trial 2, which complicates comparison with continued PAP therapy. Reduction in AHI is not the same as resolution of sleep apnoea, and tirzepatide is not a substitute for PAP in every patient.

How should this be read, and how should it not?

It describes the product that was studied. Every figure here was collected on the FDA-approved product. No compounded preparation has a trial of its own, and no figure on this page transfers to one.
It describes the dose that was studied. A microdose sits below the range trialled here, so no result on this page applies to one at any price.
It describes the population that was studied. A result in people with established cardiovascular disease does not transfer to primary prevention, and a result in diabetes does not transfer to weight management.
It is not a dosing instruction. Your prescriber sets your regimen.

How does it compare with the other trials on this site?

Every trial we hold a record for
Trial	Intervention	Reported result	Duration
SURMOUNT-OSA	Tirzepatide once weekly at maximum	Tirzepatide reduced the apnoea-hypopnoea index, body weight, hypoxic burden, hsCRP and sys	52 weeks
ATTAIN-1	Orforglipron, once-daily oral non-	Approximately 11% to 12.4% mean weight reduction at the highest dose over 72 weeks. Lilly	72 weeks
OASIS 4	Oral semaglutide 25 mg once daily,	13.6% mean weight reduction on the treatment-policy estimand versus 2.2% placebo; 16.6% ve	64 weeks of treatment
SELECT	Semaglutide	Approximately a 20% relative reduction in the primary composite; event rate fell from roug	Mean follow-up approxi
STEP-1	Semaglutide	Mean weight change of −14.9% against −2.4% on placebo; about 86% reached 5% or more, about	68 weeks
STEP-8	Semaglutide 2.4 mg weekly	Mean weight change approximately −15.8% on semaglutide against approximately −6.4% on lira	68 weeks
SUMMIT	Tirzepatide once weekly at maximum	A 38% reduction in the combined endpoint of cardiovascular death and worsening heart-failu	52 weeks to the sympto
SURMOUNT-1	Tirzepatide once weekly	Treatment-regimen estimand: −15.0% (5 mg), −19.5% (10 mg), −20.9% (15 mg) versus −3.1% pla	72 weeks
SURMOUNT-1, three-year prediabetes analysis	Tirzepatide once weekly	Three years of tirzepatide produced substantial sustained weight reduction and a markedly	176 weeks of treatment
SURMOUNT-3	not stated	−18.4% additional reduction versus +2.5% with placebo, on top of lead-in weight loss	72 weeks

Separate trials with different populations, durations and endpoints. Only a head-to-head supports a direct comparison between two drugs; the rest sit side by side here for reference, not for subtraction.

Frequently asked questions

Does this mean I would lose that much weight?

No. Trials report group averages under controlled conditions with specific eligibility criteria. Individual results vary widely, and the trial population may not resemble you.

Do these results apply to compounded tirzepatide?

Not automatically. Trials studied the approved product at studied doses. A compounded preparation at a different concentration, formulation or route has not been through those trials.

Research hubResearch
SURMOUNT-1 Tirzepatide Trial ExplainedResearch
SURMOUNT-3 Tirzepatide Trial ExplainedResearch
SURMOUNT-4: Weight Maintenance and Tirzepatide WithdrawalResearch
Provider ranking methodologyCore & Trust
GLP-1 total cost calculatorTools
Download the pricing recordsData
Tirzepatide and Chronic Kidney DiseaseResearch
Tirzepatide and Cardiovascular OutcomesResearch
Tirzepatide Clinical Trial FinderTools

Cite this pageCC BY 4.0

GLP-1 Semaglutide Rx. “SURMOUNT-OSA and Tirzepatide for Sleep Apnea.” S.J Partners LLC, 2026-08-03. https://glp1semaglutiderx.com/research/surmount-osa/

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