Metabolic & Cardiometabolic
tirzepatide causes greater weight loss than semaglutide
In plain terms: Does tirzepatide (Zepbound/Mounjaro) take off more weight than semaglutide (Wegovy/Ozempic)?
Part of: 💊 GLP-1 Drugs
Yes — the head-to-head SURMOUNT-5 trial and network meta-analyses show tirzepatide produces several percentage points more weight loss than semaglutide.
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
How the studies fall
The evidence (12)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Wang 2026 · J Med Econ | observational | supports | low | Cost-effectiveness analysis built on SURMOUNT-5 confirms greater weight loss with tirzepatide as its efficacy premise. |
| McGowan 2025 · Nat Med | meta-analysis | supports | high | SR/MA of obesity pharmacotherapy: tirzepatide ranks above semaglutide for weight loss magnitude. |
| Damen 2026 · Ann Intern Med | meta-analysis | supports | high | ACP living NMA: tirzepatide among most efficacious for weight loss, ahead of semaglutide. |
| Zhou 2024 · Metabolism | meta-analysis | supports | moderate | MASLD NMA ranks GLP-1/GIP polyagonists above GLP-1RA on weight, consistent with tirzepatide>semaglutide. |
| de Mesquita 2023 · Int J Obes | meta-analysis | supports | moderate | MA of tirzepatide RCTs: large dose-dependent weight loss (up to ~21%), exceeding typical semaglutide magnitudes. |
| Aronne 2024 · JAMA | RCT | supports | moderate | SURMOUNT-4: tirzepatide lead-in achieved 20.9% loss over 36wk, exceeding semaglutide STEP magnitudes (indirect). |
| Verma 2026 · Eur Heart J Open | observational | supports | low | SURMOUNT-5 post-hoc: predicted greater CV risk reduction with tirzepatide tracks its larger weight-loss effect. |
| Wilding 2021 · N Engl J Med | RCT | supports | moderate | STEP-1 anchor: semaglutide 2.4mg ~14.9% loss — the benchmark SURMOUNT-5 tirzepatide (-20.2%) exceeds head-to-head. |
| Frias 2021 · N Engl J Med | RCT | mixed | high | SURPASS-2 (T2D): tirzepatide beat semaglutide on HbA1c and weight, BUT comparator semaglutide was 1mg, not the 2.4mg obesity dose. |
| Xie 2025 · Diabetes Metab Syndr Obes | meta-analysis | mixed | moderate | SR comparing GLP-1/GIP co-agonists vs GLP-1RA: greater weight loss with co-agonists, offset by more GI adverse events. |
| Hamarsheh 2026 · Endocrinol Diabetes Metab | meta-analysis | supports | moderate | NMA: tirzepatide (and CagriSema) yield greater weight reduction than semaglutide; indirect comparisons. |
| Aronne 2025 · N Engl J Med | RCT | supports | high | SURMOUNT-5 head-to-head (obesity, no diabetes): tirzepatide -20.2% vs semaglutide -13.7% at wk72 (P<0.001); superior on all weight thresholds. |
Disagree, or know a study we missed?
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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.