HGH Fragment 176-191

HGH Fragment 176-191 consists of amino acids 176 to 191 of the human growth hormone sequence — the C-terminal region responsible for GH's lipolytic (fat-burning) activity. This fragment stimulates lipolysis and inhibits lipogenesis by binding to β3-adrenergic receptors on adipocytes, independently of the full GH molecule's growth-promoting and insulin-like effects on other tissues. It does not bind to the classic GH receptor, does not raise IGF-1 levels, and does not affect blood glucose or insulin sensitivity. AOD-9604 was developed from this fragment at Monash University with a specific modification (tyrosine substitution at position 177) to improve stability and bioavailability — making AOD-9604 essentially an optimised version of HGH Fragment 176-191. Both compounds produce similar fat loss effects; AOD-9604 is considered the more pharmaceutically refined form.

The fragment was first identified in the 1970s as the active lipolytic domain of human growth hormone. The foundational research by Ng et al. at Monash University demonstrated that isolating this fragment produced fat loss equivalent to full GH without growth-promoting or diabetogenic side effects — observations that led directly to the development of AOD-9604 as a pharmaceutical candidate. Phase I, II, and III trials were conducted for AOD-9604 (the modified form) rather than the pure fragment. HGH Fragment 176-191 remains available through compounding pharmacies in Australia as an alternative to AOD-9604, typically at lower cost. For users comparing options, AOD-9604 represents the clinically trialled, slightly more stable evolution of this compound.

12 weeks