What is Retatrutide?
9 September 2026
Overview
Retatrutide (LY3437943) is an investigational synthetic peptide with activity at three metabolic receptors: glucose-dependent insulinotropic polypeptide (GIP), glucagon-like peptide-1 (GLP-1) and glucagon. Acting on all three from a single molecule is what sets it apart from the single- and dual-agonist peptides that preceded it.
Mechanism of action
Because the three pathways are engaged together, researchers can study how they interact rather than each in isolation. GIP and GLP-1 receptor activation is associated with glucose-dependent insulin secretion and satiety signalling; glucagon receptor agonism is associated with higher energy expenditure and changes in hepatic lipid metabolism.
Research applications
Preclinical and clinical work with Retatrutide has looked at:
- Metabolic regulation – glucose homeostasis and insulin sensitivity
- Body composition – changes in adipose tissue distribution
- Hepatic lipid content – potential effects on liver fat reduction
- Energy expenditure – thermogenic pathways via glucagon signalling
Molecular profile
| Property | Detail |
|---|---|
| Sequence length | 39 amino acids |
| Receptor targets | GIP, GLP-1, Glucagon |
| Administration | Subcutaneous (research) |
| Molecular class | Synthetic peptide |
References
- Coskun T, et al. "LY3437943, a novel triple GIP/GLP-1/glucagon receptor agonist." Cell Metabolism, 2022.
- Jastreboff AM, et al. "Triple-hormone-receptor agonist retatrutide for obesity." NEJM, 2023.
Draft wording prepared 2026-09-09, awaiting approval by Aevryn Labs Pty Ltd.