Compound comparison

Retatrutide vs Tirzepatide

Both are engineered incretin peptides, and both act on more than one receptor — which is what separates them from semaglutide. The difference between them comes down to one additional target.

Tirzepatide is a dual agonist, binding the GIP and GLP-1 receptors. Retatrutide adds a third: the glucagon receptor. That third target is the whole distinction, and it is also why the two sit at different stages of clinical development.

Side by side

	Retatrutide	Tirzepatide
GLP-1 receptor activity	Yes	Yes
GIP receptor activity	Yes	Yes
Glucagon receptor activity	Yes	No
Number of receptor targets	Three	Two
Development stage	Investigational — Phase 2 published, Phase 3 ongoing	Approved as a finished pharmaceutical in several jurisdictions
Peptide length	39 amino acids	39 amino acids
Published human trial data	Phase 2 (obesity, MASLD)	Phase 3 programmes (SURPASS, SURMOUNT)
Supplied as	Lyophilized powder	Lyophilized powder and pre-loaded pens

Choosing between them

Researchers work with retatrutide when

the glucagon-receptor arm is the point of the study. Glucagon agonism is associated in the literature with energy expenditure and hepatic lipid mobilisation — effects the dual agonists do not produce. It is also the compound of interest for anyone tracking where the incretin field is heading.

Researchers work with tirzepatide when

an established evidence base matters more than novelty. Tirzepatide has completed Phase 3 development with published outcomes across both glycaemic and weight endpoints, so it functions as a reference compound in a way retatrutide cannot yet.

Retatrutide 100mg Kit

10mg • 10 Vials

$390.00

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Tirzepatide 100mg Kit

10mg • 10 Vials

$295.00

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Common questions

Is retatrutide stronger than tirzepatide?

That framing does not map onto the pharmacology. They engage different numbers of receptors, and the trials were run to different protocols at different stages, so cross-trial comparison is not valid. What can be said factually is that retatrutide engages a third receptor tirzepatide does not.

Why does the glucagon receptor matter?

It is counter-intuitive in a metabolic compound, since glucagon raises blood glucose. The research rationale is that its effects on energy expenditure and hepatic fat handling operate alongside the glucose-lowering incretin arms rather than against them.

Is retatrutide approved anywhere?

No. It remains investigational with published Phase 2 data and Phase 3 trials in progress. Tirzepatide is approved as a finished pharmaceutical in several jurisdictions.

This comparison covers structure, receptor targets and development stage — matters of published record. It does not rank the compounds or claim either produces better outcomes. Much of the supporting literature is preclinical. All products are supplied for laboratory research use only.

See the studies behind both compounds →