What is the difference between Retatrutide and Tirzepatide?

Retatrutide (Retatrutide (LY3437943)) is graded A and is Not FDA-approved — Phase 3 trials (TRIUMPH program) for obesity. Tirzepatide (Tirzepatide (Mounjaro / Zepbound)) is graded A+ and is FDA-approved for weight management and type 2 diabetes. They are commonly compared because they share the categories: weight-loss, metabolic.

Which has stronger clinical evidence — Retatrutide or Tirzepatide?

On our internal evidence scale, Retatrutide is A and Tirzepatide is A+. A+ indicates large RCTs plus FDA approval; C indicates primarily preclinical or anecdotal evidence.

What is the typical dose of Retatrutide vs Tirzepatide?

Retatrutide: Trial range: 1–12 mg weekly (subcutaneous). Tirzepatide: 2.5–15 mg weekly (subcutaneous injection). Always work with a licensed clinician — peptide dosing should be individualized.

Retatrutide vs Tirzepatide

Both Retatrutide and Tirzepatide are used for weight-loss and metabolic. Here's how their evidence, dosing, and regulatory status actually compare.

Retatrutide

Evidence A

Retatrutide (LY3437943)

Triple agonist at GLP-1, GIP, and glucagon receptors. Phase 2 produced 24.2% mean weight reduction at 48 weeks — the highest ever in a clinical obesity trial.

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Tirzepatide

Evidence A+

Tirzepatide (Mounjaro / Zepbound)

A dual GIP/GLP-1 receptor agonist that achieved up to 22.5% mean weight loss in the SURMOUNT-1 trial — the highest of any FDA-approved weight loss medication.

View full Tirzepatide profile →

Side-by-Side

Attribute	Retatrutide	Tirzepatide
Evidence Grade	A	A+
FDA Status	Not FDA-approved — Phase 3 trials (TRIUMPH program) for obesity	FDA-approved for weight management and type 2 diabetes
Typical Dose	Trial range: 1–12 mg weekly (subcutaneous)	2.5–15 mg weekly (subcutaneous injection)
Clinics Indexed	12	1,850
Categories	weight-loss, metabolic	weight-loss, metabolic

Key reported benefits — Retatrutide

✓Highest reported weight loss
✓Triple incretin/glucagon mechanism
✓Metabolic improvement

Key reported benefits — Tirzepatide

✓Superior weight loss
✓Dual hormone targeting
✓Blood sugar control
✓Reduced cardiovascular risk

Educational use only

This comparison is for educational purposes and not medical advice. Peptide selection should be made with a licensed medical professional based on your individual goals, health history, and current evidence quality.

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