Tesamorelin: a GHRH analogue

Tesamorelin is a synthetic analogue of growth-hormone-releasing hormone (GHRH), the signal the hypothalamus uses to prompt the pituitary gland. Small changes to its structure make it more stable than the natural hormone, which is why it has become a reference compound in growth-hormone-axis research.

A stabilised version of GHRH

Natural GHRH is broken down quickly in the body, which limits how long it can act. Tesamorelin carries a modification that protects it from rapid enzymatic degradation, extending its stability in laboratory models. Because it mirrors the body's own GHRH, it is studied as a way to engage the growth-hormone axis at its natural starting point — the pituitary — rather than introducing growth hormone directly.

What researchers study it for

In the research literature, tesamorelin is examined for its role in stimulating the pituitary's own release of growth hormone. This "upstream" approach interests researchers because it works through the body's existing feedback loops rather than overriding them. Much of the published work focuses on metabolic markers and body-composition parameters in study models.

GHRH versus secretagogue peptides

Tesamorelin belongs to the GHRH family, which acts on one specific receptor. It is often studied alongside growth-hormone-releasing peptides (GHRPs) such as ipamorelin, which act through a different receptor. Our overview of growth hormone secretagogues explains how the two families differ and why they are frequently compared.

Form and documentation

Tesamorelin is supplied as a lyophilised powder and reconstituted with bacteriostatic water before use; every Vela order includes a free 3 mL bacteriostatic water vial. Each batch ships with a certificate of analysis issued within six months of sale, documenting identity and purity.