Tesamorelin (Egrifta) holds a unique distinction among metabolic peptides: it is the only FDA-approved peptide specifically indicated for visceral fat reduction. Approved in 2010 for HIV-associated lipodystrophy, its mechanism and clinical evidence have made it increasingly relevant for broader visceral fat reduction applications in GH-deficient adults.
Mechanism: GHRH Analog
Tesamorelin is a synthetic analog of growth hormone-releasing hormone (GHRH) that stimulates the pituitary gland to produce and release GH in a pulsatile, physiological pattern. This is distinct from exogenous GH administration — tesamorelin works through the body's own regulatory mechanisms, preserving the feedback loops that prevent supraphysiological GH levels.
FDA Approval and Clinical Evidence
The GHRH0208 trials demonstrated 15-20% reduction in visceral adipose tissue (VAT) over 26 weeks at 2mg/day. VAT reduction was maintained at 52 weeks with continued treatment. Importantly, the visceral fat reduction occurred without significant changes in subcutaneous fat, confirming a specific effect on the metabolically dangerous visceral depot.
Why Visceral Fat Matters
Visceral fat — the fat surrounding abdominal organs — is metabolically distinct from subcutaneous fat. It secretes pro-inflammatory adipokines, contributes to insulin resistance, and is independently associated with cardiovascular disease, type 2 diabetes, and all-cause mortality. Reducing visceral fat has metabolic benefits beyond what the scale shows.