Retatrutide

What Is Retatrutide?

Retatrutide (CAS 2381089-83-2; also known as LY3437943) is a 39-amino acid synthetic peptide engineered as a triple agonist of three distinct metabolic receptors: glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon (GCG). Its structure carries a C-20 fatty diacid conjugated to the peptide backbone, extending the plasma half-life. CertaPeptides supplies retatrutide in lyophilized powder form from 5mg through 50mg per vial.

CAS: 2381089-83-2. Alternate identifier: LY3437943. Molecular weight: 4731.33 g/mol. Receptor-engagement profile: GIP-R, GLP-1R, and GCG-R simultaneously.

How Retatrutide Is Studied in the Literature

Retatrutide is characterised in the published peptide-research literature primarily through its triple-receptor pharmacology and its effects in preclinical metabolic models. The notes below describe the research context in which the molecule is investigated. They are reported for scientific background only and are not claims about what CertaPeptides’ research compound will do in any individual.

Body-composition and energy-expenditure research

In preclinical and in-vitro metabolic models, retatrutide is studied for its effects on body composition, adiposity, and energy-expenditure pathways. Researchers investigate how simultaneous engagement of GIP-R, GLP-1R, and GCG-R modulates these processes relative to single- and dual-receptor agonists.

Glucose-regulation pathway research

Retatrutide is also investigated in metabolic models for its role in glucose-regulation and incretin signalling pathways, including the dose-dependent receptor pharmacology that underlies its activity at the three target receptors.

Within the Incretin Class — How Retatrutide Differs

Retatrutide is studied alongside two other research peptides in the same metabolic class: semaglutide (single GLP-1R agonist) and tirzepatide (dual GIP/GLP-1R agonist). The three differ structurally and mechanistically in ways that shape how each compound is studied:

Feature	Semaglutide	Tirzepatide	Retatrutide
Receptor engagement	GLP-1R (single)	GIP-R + GLP-1R (dual)	GIP-R + GLP-1R + GCG-R (triple)
Amino acid count	31	39	39
Molecular weight	4113.58 Da	4813.5 Da	4731.33 Da
Unique mechanistic element	Fatty-acid modification extends half-life at GLP-1R	Imbalanced biased agonism favouring GIP-R	Glucagon-receptor engagement adds hepatic glucose output & energy expenditure signals

The glucagon-receptor arm is the distinguishing feature: neither semaglutide nor tirzepatide activates GCG-R. In research contexts this is of interest because glucagon agonism increases hepatic glucose output and thermogenesis, adding an energy-expenditure component not present in the single- or dual-agonist compounds. Researchers comparing the three frequently reference the GLP-1 class comparison overview and the molecular-level triple-receptor mechanism overview.

Research Areas Where Retatrutide Is Studied

• GIP, GLP-1, and glucagon receptor pharmacology — comparative in vitro binding and signalling assays
• Preclinical metabolic models of body composition and energy expenditure
• Comparative studies against single- and dual-agonist compounds (semaglutide, tirzepatide)
• Lipid metabolism and hepatic glucose-output pathways (glucagon-arm specific)
• Formulation and stability research for long-acting peptide analogues

Specifications

Numero CAS	2381089-83-2
Alternate identifier	LY3437943
Peso molecolare	4731.33 g/mol
Receptor profile	Triple agonist: GIP-R / GLP-1R / GCG-R
Purezza	≥ 98% (class-level specification)
Physical Form	Lyophilized (freeze-dried) powder in sealed glass vial
Available Sizes	5mg, 10mg, 15mg, 20mg, 30mg, 50mg

Conservazione

Lyophilized powder: −20°C for long-term storage. 2–8°C for short-term use before reconstitution.

Reconstituted: 2–8°C. Do not freeze after reconstitution.

Quality Assurance

• Class-level specification ≥98%
• Selected lots are independently tested by Janoshik Analytical, confirming molecular identity
• Independent test reports are searchable by batch or report code at certapeptides.com/verify
• Sold and shipped from the EU by CERTALAB S.R.L.

Important Notice — For Research Purposes Only

Retatrutide is supplied by CertaPeptides strictly as a laboratory research compound. The research context described above is drawn from the published scientific literature and is reported here for background only. It is not a medical claim and does not describe what CertaPeptides’ research material will do in any individual. It is supplied for laboratory research and is not for human or veterinary use. For laboratory research purposes only. Not for human consumption.