Retatrutide vs Tirzepatide
Side-by-side comparison of key properties, dosing, and research.
GLP-1 / Weight Loss Agonists
RetatrutideGLP-1 / Weight Loss Agonists
Tirzepatide- Summary
- Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
- Tirzepatide is an FDA-approved dual GIP/GLP-1 receptor agonist that produces greater weight loss than semaglutide in head-to-head trials. SURMOUNT-1 trial showed average 21% body weight reduction at 72 weeks at the highest dose. Marketed as Mounjaro (diabetes) and Zepbound (obesity).
- Half-Life
- ~10–12 days
- ~5 days
- Admin Route
- SubQ
- SubQ
- Research
- —
- —
- Typical Dose
- 0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
- 2.5 mg → 5 mg → 7.5 mg → 10 mg → 12.5 mg → 15 mg
- Frequency
- Once weekly
- Once weekly, subcutaneous
- Key Benefits
- ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
- Superior to both semaglutide and tirzepatide in early trial comparisons
- Triple receptor mechanism addresses multiple obesity pathways
- Significant reduction in liver fat (MASH/NAFLD indication being studied)
- Improved cardiovascular and metabolic markers
- Once-weekly dosing
- Potential for greatest weight loss of any currently investigated compound
- Average 21% body weight reduction at highest dose (SURMOUNT-1)
- Superior to semaglutide in head-to-head SURPASS trials
- Dual GIP/GLP-1 mechanism for enhanced metabolic control
- Significant reduction in HbA1c for type 2 diabetes
- Improved cardiovascular risk markers
- Reduces visceral fat preferentially
- FDA-approved for T2DM (Mounjaro) and obesity (Zepbound)
- Weekly dosing
- Side Effects
- Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
- Diarrhea
- Constipation
- Heart rate increase (from glucagon receptor agonism)
- +2 more
- Nausea (most common during titration)
- Vomiting
- Diarrhea or constipation
- Abdominal pain
- +3 more
- Stacks With
- —
- —