Tesamorelin is a synthetic analog of growth hormone–releasing hormone (GHRH), consisting of a 44–amino acid peptide sequence that stimulates the pituitary gland to increase endogenous growth hormone (GH) secretion. Through this physiological mechanism, esamorelin enhances insulin-like growth factor 1 (IGF-1) production and promotes lipolysis, particularly reducing visceral adipose tissue (VAT).

Mechanistically, Tesamorelin binds to GHRH receptors on somatotroph cells in the anterior pituitary, initiating a cAMP-mediated signaling cascade that increases GH synthesis and release. This results in downstream metabolic effects, including improved lipid metabolism, enhanced protein synthesis, and modulation of body composition.

Clinically, Tesamorelin has been shown to reduce abdominal fat without significantly affecting subcutaneous fat or glucose homeostasis. It is primarily studied for metabolic and anti-lipodystrophic applications, as well as for its potential in age-related GH decline, cognitive health, and body composition optimization.