Retatrutide: A Triple-Agonist Peptide at the Centre of Modern Metabolic Research
Retatrutide (LY3437943) is one of the most extensively reviewed metabolic research peptides of the past two years. Here's what the published literature says.
What is retatrutide?
Retatrutide (research code LY3437943) is a synthetic peptide engineered by Eli Lilly's metabolic research group as a triple-agonist of the GLP-1, GIP and glucagon receptors. Its design represents a step forward from earlier dual-agonist research peptides such as tirzepatide.
The molecule has been the subject of multiple peer-reviewed publications since 2022, primarily exploring receptor binding, signalling pathway activation and pharmacokinetic profiling in research models.
Key research papers
Coskun T, Urva S, Roell WC, et al. described the discovery and pharmacology of retatrutide in Cell Metabolism (2022; 34(9):1234–1247), characterising its triple-agonist receptor activity profile.
Jastreboff AM, Kaplan LM, Frias JP, et al. (NEJM 2023; 389(6):514–526) reported a Phase 2 dose-ranging study describing how the molecule behaves under the conditions tested in their protocol.
Subsequent 2024–2025 publications continue to investigate receptor signalling, formulation stability and downstream pathways referenced in the original research literature.
Why researchers reference it
The scientific interest in retatrutide derives from its unique receptor profile compared with single- or dual-agonist research peptides. For laboratory researchers, it provides a useful comparator molecule when investigating triple-receptor signalling cascades, peptide stability profiles or assay development across the GLP-1 / GIP / glucagon axes.
Peptigen Labs supplies retatrutide strictly as a research material — lyophilised, batch-documented, and intended only for qualified laboratory researchers studying receptor pharmacology, peptide chemistry or related research questions.
Storage and handling
Lyophilised retatrutide should be stored at 2-8°C in its original sealed vial. For long-term storage, many laboratories transfer to -20°C in airtight conditions.
Reconstitution decisions, diluent choice and downstream handling are entirely the responsibility of the qualified researcher. Peptigen Labs does not provide reconstitution or use guidance.
Researcher FAQs
What is retatrutide?
Retatrutide (LY3437943) is a synthetic research peptide engineered by Eli Lilly as a triple-agonist active at the GLP-1, GIP and glucagon receptors. It is supplied to qualified researchers as a lyophilised laboratory material.
Where is retatrutide research published?
Foundational pharmacology was published in Coskun T, et al. (Cell Metabolism 2022;34(9):1234-1247) and a Phase 2 dose-ranging study in Jastreboff AM, et al. (NEJM 2023;389(6):514-526). Subsequent 2024-2025 publications continue to investigate receptor signalling and pharmacokinetics in research models.
How does retatrutide differ from tirzepatide?
Tirzepatide is a dual-agonist (GLP-1 + GIP receptors). Retatrutide adds glucagon-receptor activity, making it a triple-agonist. This is the principal pharmacological difference referenced in the published literature.
Does Peptigen Labs supply retatrutide in the UK?
Yes. Peptigen Labs holds UK stock of retatrutide in 10 mg, 20 mg and 30 mg vials. Orders placed before 14:00 GMT on a UK working day are dispatched the same day with tracked next-day Royal Mail delivery. Every batch ships with an independent Certificate of Analysis from the Brown Institute of Biomolecular Research.
How should retatrutide be stored?
Lyophilised retatrutide is stored at 2-8°C in the original sealed vial. For long-term archive many laboratories transfer to -20°C in airtight conditions. Reconstitution, diluent selection and downstream handling are decisions for the qualified researcher.
- Coskun T, Urva S, Roell WC, et al. Cell Metabolism. 2022;34(9):1234-1247.
- Jastreboff AM, Kaplan LM, Frias JP, et al. New England Journal of Medicine. 2023;389(6):514-526.
This article describes published research literature only. It is not medical, dosing, administration, therapeutic, veterinary or human-use guidance. Peptigen Labs material is supplied strictly for laboratory research use only.