GPL – 3, chemically known as Retatrutide, represents a breakthrough in peptide engineering as a single molecule capable of tri-agonism. It is structurally composed of a 39-amino-acid backbone with a C20 fatty diacid moiety attached, which binds efficiently to serum albumin. This modification drastically extends its half-life, allowing researchers to conduct prolonged observational studies without the need for frequent dosing in animal models.

Current laboratory applications are heavily focused on its synergistic mechanism of action. By concurrently binding to the gastric inhibitory polypeptide (GIP), glucagon-like peptide-1 (GLP-1), and glucagon (GCG) receptors, researchers utilize GPL – 3 to observe dramatic shifts in energy expenditure and lipid metabolism. In-vitro and in-vivo models are currently studying its unique ability to clear hepatic fat (liver lipid accumulation) and aggressively upregulate metabolic basal rates beyond the capabilities of single or dual agonists.