SURMOUNT-OSA: A Study of Tirzepatide in Adults with Obesity and Moderate-to-Severe Obstructive Sleep Apnea

Background + significance

SURMOUNT-OSA was two parallel trials testing tirzepatide in adults with obesity + moderate-to-severe OSA (with and without CPAP). Led to FDA approval of Zepbound for OSA (December 2024) — the first weight-loss drug approved for OSA. Major impact on Medicare coverage paths.

Trial design

Sponsor

Eli Lilly

Phase

Phase 3

Participants

469

Duration

52 weeks

ClinicalTrials.gov ID

NCT05412004

Drugs tested

• Zepbound (tirzepatide 10/15 mg)Active

Primary outcome

Change in apnea-hypopnea index (AHI) from baseline to week 52

−25 to −29 events/hour mean reduction on tirzepatide vs −5 events/hour placebo

Secondary outcomes

• •Improvements in patient-reported sleep quality
• •Reduced CPAP dependence in some patients
• •Body-weight reduction 18-20%

Why it matters

1. 1.First trial of a weight-loss drug in OSA as primary outcome.
2. 2.FDA-approved indication added December 2024.
3. 3.Opens Medicare coverage path for some Zepbound patients (OSA is a covered indication, weight management is not).