Tirzepatide vs Semaglutide 2026: Head-to-Head Weight Loss Results From SURMOUNT-5
By Dr. Sarah Mitchell, Respiratory Equipment Specialist · Published 2026-06-03 · 8 min read
New SURMOUNT-5 trial data shows Zepbound (tirzepatide) drives 47% more weight loss than Wegovy (semaglutide). See the full comparison.
The First Direct Head-to-Head GLP-1 Trial
The SURMOUNT-5 trial (published NEJM 2026) directly compared tirzepatide (Zepbound) vs semaglutide (Wegovy) in 751 adults with obesity over 72 weeks.
Weight Loss Results
- Tirzepatide: 20.2% average body-weight reduction
- Semaglutide: 13.7% average body-weight reduction
- Tirzepatide delivered 47% more total weight loss
Why Tirzepatide Wins
Tirzepatide is a dual GIP/GLP-1 agonist — it activates two gut hormones instead of one. The added GIP pathway boosts satiety and insulin sensitivity simultaneously.
Side Effect Profile (2026 data)
- Nausea: ~25% on both
- Diarrhea: slightly higher on tirzepatide
- Discontinuation rate: 6.1% (tirzepatide) vs 8.0% (semaglutide)
Sleep Apnea Bonus
SURMOUNT-OSA showed tirzepatide cut AHI by 63% in patients with moderate-severe OSA. Many can downgrade from full CPAP to a lighter travel CPAP within 12 months.
Cost & Access (2026)
- Zepbound: ~$1,060/mo cash, $25/mo with savings card
- Wegovy: ~$1,350/mo cash, $0–$225 with coupon
- Medicare Part D now covers both for OSA, sleep apnea, and CV risk indications
Bottom line: If your insurance covers either, tirzepatide is the more powerful choice for both weight and sleep apnea reduction.