Research Comparison

Retatrutide vs Tirzepatide

In Short

Retatrutide is gip / glp-1 / glucagon triple-receptor agonist; Tirzepatide is gip / glp-1 dual-receptor agonist. Both are supplied as lyophilized powders for laboratory and in-vitro research use only. The table below compares their molecular data, half-life and research focus side by side.

	Retatrutide	Tirzepatide
Classification	GIP / GLP-1 / glucagon triple-receptor agonist	GIP / GLP-1 dual-receptor agonist
Molecular formula	C223H343F3N46O70	C225H348N48O68
Molecular weight	4731.33 g/mol	4813.5 g/mol
CAS number	2381089-83-2	2023788-19-2
Research half-life	~6 days (supports once-weekly dosing in clinical studies)	~5 days (once-weekly in clinical research)
Primary research focus	GIP/GLP-1/Glucagon receptor agonist research	GIP/GLP-1 dual receptor agonist research
Form	Lyophilized powder	Lyophilized powder
Price from	$50.00	$50.00

Retatrutide

Retatrutide is a first-in-class triple-agonist peptide that simultaneously activates glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon receptors. Its mechanism of action involves binding all three receptor systems to modulate appetite signaling, glucose homeostasis, and energy expenditure through complementary metabolic pathways. In a phase 2 clinical trial published in the New England Journal of Medicine (Jastreboff et al., 2023), participants receiving 12 mg of retatrutide achieved a mean body weight reduction of approximately 24.2% at 48 weeks, surpassing results observed with dual-agonist compounds like tirzepatide. The glucagon receptor component is believed to contribute additional energy expenditure and hepatic lipid metabolism benefits not seen with GLP-1-only or GIP/GLP-1 dual agonists. Compared to semaglutide (GLP-1 only) and tirzepatide (GIP/GLP-1 dual), retatrutide represents an expansion of the incretin-based approach by incorporating glucagon receptor activation, which studies suggest enhances thermogenesis and fat oxidation. For research use, the lyophilized powder should be stored at -20C and reconstituted with bacteriostatic water immediately before use; reconstituted solutions remain stable under refrigeration at 2-8C for up to 28 days. This compound is primarily investigated by academic metabolic research centers, pharmaceutical R&D divisions, and endocrinology laboratories studying multi-receptor agonism as a strategy for metabolic syndrome research.

Full Retatrutide research guide

Tirzepatide

Tirzepatide is a synthetic 39-amino-acid peptide engineered to act as a dual agonist at the glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) receptors. By engaging both incretin pathways, it has been investigated in research models for effects on insulin secretion, glucagon suppression, gastric emptying, appetite signaling, and adipose tissue metabolism. It is frequently used as a comparator alongside GLP-1-only agonists such as semaglutide and triple agonists such as retatrutide in metabolic research. Supplied as a lyophilized powder for in-vitro and laboratory research use only; not for human consumption.

Full Tirzepatide research guide

Frequently Asked Questions

What is the main difference between Retatrutide and Tirzepatide?

Retatrutide is classified as gip / glp-1 / glucagon triple-receptor agonist, while Tirzepatide is gip / glp-1 dual-receptor agonist. They are distinct research compounds with different mechanisms — the comparison table above sets out the molecular and pharmacokinetic differences side by side.

Can Retatrutide and Tirzepatide be studied together?

Some research protocols evaluate related peptides in combination, and research blends exist. Combination study design depends entirely on the research question and model. Both compounds are supplied for laboratory and in-vitro research use only — not for human use.

Are Retatrutide and Tirzepatide legal to buy for research?

Both are sold in the United States as research chemicals for laboratory and in-vitro use only. Neither is FDA-approved for human use. Researchers are responsible for compliance with all applicable regulations.

Buy Retatrutide

From $50.00 — ≥98% HPLC, COA included.

Buy Tirzepatide

From $50.00 — ≥98% HPLC, COA included.

Research Use Only. This comparison summarizes published research. It is not medical advice. Neither compound is for human consumption or FDA-approved.