Tesamorelin — Synthetic GHRH analogue — FDA-approved growth hormone-releasing hormone receptor agonist (Schedule V controlled substance considerations vary by jurisdiction)

Tesamorelin is a synthetic analogue of the full-length 44-amino acid human growth hormone-releasing hormone (GHRH) stabilized with a trans-3-hexenoic acid group at the N-terminus, which confers resistance to dipeptidyl peptidase IV (DPP-IV) degradation and extends plasma half-life. Acts via GHRH receptor (GHRH-R) on pituitary somatotrophs to stimulate pulsatile GH secretion, which in turn elevates hepatic IGF-1 production. Compared to GHRP-class secretagogues (which act via GHS-R1a): (1) tesamorelin is purely GHRH-R mediated — no appetite stimulation, no cortisol/prolactin elevation; (2) GH pulses are more physiological (respects feedback via somatostatin) — lower tachyphylaxis risk; (3) Specifically validated in HIV lipodystrophy: reduces visceral adiposity via GH-mediated lipolysis (PA-IGFBP-3 axis). FDA indication is NARROW: HIV-associated lipodystrophy (excess visceral fat secondary to ART).