Overview
Retatrutide (LY3437943) is a synthetic triple receptor agonist that simultaneously engages the GLP-1 receptor, the GIP receptor, and the glucagon receptor. This triple-axis pharmacology distinguishes it from dual agonists such as tirzepatide and single agonists such as semaglutide, making it the most structurally complex incretin-class compound currently available for laboratory research.
Three Receptor Axes
Retatrutide's research profile is defined by its simultaneous activity at three distinct receptor systems:
A class B GPCR central to incretin signalling. Expressed in pancreatic beta cells, neuronal populations, and peripheral tissues. GLP-1R activation stimulates cAMP and potentiates glucose-stimulated insulin secretion.
Co-expressed in beta cells and adipose tissue. GIPR activation produces synergistic incretin effects when combined with GLP-1R agonism, a central focus of dual and triple agonist research.
The glucagon receptor (GCGR) mediates hepatic glucose output and plays a distinct role in energy expenditure and fatty acid oxidation. Its integration into a triple agonist creates complex, interacting downstream effects across metabolic pathways.
Triple vs Dual Agonism in Research
The addition of a glucagon receptor axis creates a pharmacological profile distinct from tirzepatide. Research into this profile examines how simultaneous tri-receptor activation alters the balance of hepatic glucose regulation, adipose tissue signalling, and central appetite pathways compared to dual or single agonist models.
Researchers use retatrutide to study receptor hierarchy and crosstalk — which receptor axis dominates under which conditions, and how downstream cAMP and beta-arrestin signalling is shared between three simultaneously activated GPCRs. This makes retatrutide a particularly valuable tool for mapping the functional consequences of receptor interaction within complex signalling networks.
Research Applications
Retatrutide is studied across a range of laboratory models, including:
- Hepatocyte glucose and lipid output assays
- Adipocyte lipolysis and energy substrate utilisation models
- Pancreatic alpha and beta cell receptor interaction studies
- Receptor pharmacology comparing single, dual, and triple agonist profiles
- Energy homeostasis pathway mapping across metabolic cell systems
All research is conducted in vitro. Retatrutide supplied by Nova Biolabs is for laboratory research use only and is not intended for human or veterinary use.
Available from Nova Biolabs
Nova Biolabs supplies lyophilised retatrutide in 10mg and 30mg vial sizes, held in UK domestic stock. All products are for laboratory research use only.