Retatrutide
Research OnlyStrong EvidenceRetatrutide (GLP-1/GIP/Glucagon Triple Agonist)
The first triple incretin agonist (GLP-1/GIP/Glucagon) in late-stage trials — Phase II data shows ~24% weight reduction, potentially surpassing tirzepatide.
Half-Life
~6 days (weekly dosing)
Molecular Weight
~5000 g/mol (estimated)
Retatrutide (LY3437943) is a first-in-class triagonist simultaneously activating GLP-1, GIP, and glucagon receptors. Adding glucagon receptor agonism to the dual GLP-1/GIP mechanism of tirzepatide theoretically enhances energy expenditure (via glucagon's thermogenic and lipolytic effects) while maintaining GLP-1-mediated appetite suppression and GIP-mediated insulin sensitization. Phase II results (NEJM, 2023) showed 24.2% mean body weight reduction at 48 weeks — the largest pharmacological weight loss ever reported in a clinical trial. Phase III trials are ongoing. Not yet FDA-approved.
Also Known As
Amino Acid Sequence
Proprietary Eli Lilly sequence — modified GLP-1/GIP/GCG hybrid with fatty acid conjugation
Reconstitution
Research peptide: reconstitute with bacteriostatic water. Precise dosing is critical given potency.
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