Semaglutide vs Tirzepatide
Head-to-head comparison of the two leading GLP-1 class medications for diabetes and weight management.
Last updated: January 19, 2026
Semaglutide
Tirzepatide
Overview
Both semaglutide and tirzepatide are FDA-approved incretin-based therapies for type 2 diabetes and weight management. Tirzepatide is the newer dual agonist, while semaglutide has more long-term data and cardiovascular outcomes evidence.
Mechanism Comparison
| Aspect | Semaglutide | Tirzepatide |
|---|---|---|
| Target Receptors | GLP-1 only | GIP + GLP-1 |
| Receptor Activity | Single agonist | Dual agonist |
| Unique Feature | Oral formulation available | Novel dual mechanism |
Efficacy Comparison (SURPASS-2)
The SURPASS-2 trial directly compared these medications [PMID: 34170647]:
| Outcome | Tirzepatide 15mg | Semaglutide 1mg |
|---|---|---|
| HbA1c Reduction | -2.30% | -1.86% |
| Weight Loss | -11.2 kg | -5.7 kg |
| ≥10% Weight Loss | 57% | 25% |
Important: This compared semaglutide 1mg (diabetes formulation), not 2.4mg (Wegovy).
Weight Loss Comparison
Maximum Weight Loss in Trials
| Medication | Trial | Population | Max Weight Loss |
|---|---|---|---|
| Semaglutide 2.4mg | STEP 1 | Obesity | -14.9% |
| Tirzepatide 15mg | SURMOUNT-1 | Obesity | -22.5% |
Cardiovascular Evidence
| Aspect | Semaglutide | Tirzepatide |
|---|---|---|
| CV Outcomes Trial | SELECT (completed) | SURPASS-CVOT (ongoing) |
| CV Benefit Proven | Yes (20% MACE reduction) | Pending |
| Indication | Established CVD | Pending |
Administration
| Aspect | Semaglutide | Tirzepatide |
|---|---|---|
| Routes | SC injection + Oral | SC injection only |
| Formulations | Ozempic, Wegovy, Rybelsus | Mounjaro, Zepbound |
Tolerability
GI side effects are similar between both medications, with nausea, vomiting, and diarrhea being most common. Tirzepatide may have slightly higher initial GI effects but similar rates with titration.
Cost and Access
Both medications are expensive; coverage varies by insurance and indication.
Summary
- Tirzepatide shows greater weight loss and HbA1c reduction in head-to-head trials
- Semaglutide has longer track record and proven cardiovascular benefit
- Both are effective for diabetes and weight management
- Choice depends on individual factors, insurance coverage, and treatment goals
This comparison is for educational purposes only. Consult a healthcare provider for treatment decisions.
View Full Dossiers
Stay Updated on Peptide Comparisons
Get notified when we publish new comparison dossiers and evidence reviews.
No spam. Unsubscribe anytime.
Disclaimer: This comparison is for educational purposes only and does not constitute medical advice. Individual responses to medications vary. Always consult a qualified healthcare provider before making treatment decisions.