Synthetic incretin-class peptide; unimolecular triple agonist of the GIP receptor

Retatrutide

Also known as LY3437943 · LY-3437943 · Triple G · GGG tri-agonist

Retatrutide is a unimolecular synthetic peptide that acts as a balanced agonist at three class B1 G-protein-coupled receptors: the GIP receptor (GIPR), GLP-1 receptor (GLP-1R), and glucagon receptor (GCGR).

Retatrutide - HappyTides research vial
ClassSynthetic incretin-class peptide; unimolecular triple agonist of the GIP receptor
Molecular weight4731.33 g/mol (average mass, free base)
Molecular formulaC221H342N46O68
CAS number2381089-83-2

The overview

What is Retatrutide?

Retatrutide is a unimolecular synthetic peptide that acts as a balanced agonist at three class B1 G-protein-coupled receptors: the GIP receptor (GIPR), GLP-1 receptor (GLP-1R), and glucagon receptor (GCGR). In recombinant cell systems each receptor couples to Gs, so agonist binding drives adenylyl-cyclase activation and intracellular cAMP accumulation, the standard in-vitro readout used to quantify potency. In cell-based cAMP assays the molecule shows relatively greater GIPR activity with comparatively balanced GLP-1R and GCGR engagement. Cryo-electron microscopy of the peptide bound to each receptor-Gs complex shows a conserved N-terminal interaction that inserts into the orthosteric transmembrane pocket to trigger the active-state conformation, while sequence variations in the mid-region peptide are read out by receptor-specific extracellular-loop (ECL1/ECL2) and TM1-tip contacts, rationalizing simultaneous tri-receptor activation. Non-coded residues (Aib, alpha-methyl-leucine) confer protease resistance and helix stabilization, and fatty-diacid acylation promotes albumin binding for extended residence in vitro.

In the research

Where Retatrutide shows up

The areas researchers focus on with Retatrutide - and why it has the science community paying attention.

  • In-vitro GPCR pharmacology: comparative cAMP/Gs signaling potency and efficacy across GIPR, GLP-1R, and GCGR
  • Structural biology: cryo-EM of peptide-receptor-Gs ternary complexes and active-state conformational mechanism
  • Receptor selectivity and bias profiling of unimolecular multi-agonist peptides
  • Structure-activity relationship studies of non-coded residues (Aib, alpha-methyl-Leu) and lipidation on receptor engagement
  • Cellular models of incretin-receptor signaling and downstream second-messenger cascades

By the numbers

The facts that matter

Receptor targetsTriple agonist of GIPR, GLP-1R, and GCGR (all Gs-coupled class B1 GPCRs)
Developer / development codeEli Lilly and Company; code LY3437943
Molecular formulaC221H342N46O68
Average molecular weight4731.33 g/mol (free base)
CAS Registry Number2381089-83-2
Key structural modificationsAib2 and Aib20, alpha-methyl-Leu13, C-terminal amide, C20 fatty-diacid acylation via gamma-Glu/AEEA linker on Lys17
In-vitro relative potencyGreater GIPR activity with comparatively balanced GLP-1R and GCGR cAMP signaling
Activation readoutGs-coupled adenylyl cyclase / intracellular cAMP accumulation in recombinant cells

To the molecule

Molecular specifications

Molecular formulaC221H342N46O68
Molecular weight4731.33 g/mol (average mass, free base)
CAS number2381089-83-2
Amino-acid sequence39-residue synthetic peptide built on a GIP-based backbone with non-coded residues and C-terminal amidation. Reported representation: Tyr-Aib-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Ile-(alpha-Me-Leu)-Leu-Asp-Lys-Lys(gamma-Glu-AEEA-AEEA-C20 diacid)-Ala-Gln-Aib-Ala-Phe-Ile-Glu-Tyr-Leu-Leu-Glu-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2. Key modifications: Aib at position 2 and position 20, alpha-methyl-L-leucine at position 13, and fatty-diacid (C20) acylation via a gamma-Glu/AEEA linker on the Lys at position 17. (Position numbering per the cryo-EM structural paper; one-letter backbone approx. YXQGTFTSDYSIXLDKKAQXAFIEYLLEGGPSSGAPPPS-NH2 with X = non-coded residues.)

Sourced, not claimed

The science behind it

The peer-reviewed studies behind Retatrutide, linked so you can read them yourself.

  1. Coskun, T., et al. (2022). LY3437943, a novel triple GIP, GLP-1, and glucagon receptor agonist. Cell Metabolism.

Straight answers

Questions, answered

Is Retatrutide approved by the FDA?

No. Retatrutide is not an FDA-approved drug. We supply it as a research-use-only reference compound, identity-verified for purity with a COA on every vial.

What class of compound is Retatrutide?

Retatrutide is classified as: Synthetic incretin-class peptide; unimolecular triple agonist of the GIP receptor (GIPR), GLP-1 receptor (GLP-1R), and glucagon receptor (GCGR); long-acting lipidated (fatty-diacid–acylated) peptide.

What is the molecular weight of Retatrutide?

The molecular weight of Retatrutide is 4731.33 g/mol (average mass, free base), with a molecular formula of C221H342N46O68.

What is the CAS number for Retatrutide?

The CAS Registry Number for Retatrutide is 2381089-83-2.

What is the amino acid sequence of Retatrutide?

Retatrutide has the sequence: 39-residue synthetic peptide built on a GIP-based backbone with non-coded residues and C-terminal amidation. Reported representation: Tyr-Aib-Gln-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Ile-(alpha-Me-Leu)-Leu-Asp-Lys-Lys(gamma-Glu-AEEA-AEEA-C20 diacid)-Ala-Gln-Aib-Ala-Phe-Ile-Glu-Tyr-Leu-Leu-Glu-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser-NH2. Key modifications: Aib at position 2 and position 20, alpha-methyl-L-leucine at position 13, and fatty-diacid (C20) acylation via a gamma-Glu/AEEA linker on the Lys at position 17. (Position numbering per the cryo-EM structural paper; one-letter backbone approx. YXQGTFTSDYSIXLDKKAQXAFIEYLLEGGPSSGAPPPS-NH2 with X = non-coded residues.).

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