AOD-9604: The hGH Fragment Studied in Metabolic Research

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AOD-9604: The hGH Fragment Studied in Metabolic Research

The Fragment · Metabolic & GLP-1

AOD-9604 is a 16-amino acid modified C-terminal fragment of human growth hormone (positions 176–191) that retains hGH’s fat-metabolism signaling while eliminating its growth-promoting and insulin-resistance effects.

What Is AOD-9604?

AOD-9604 is a modified C-terminal fragment of hGH developed at Monash University. The “AOD” stands for Anti-Obesity Drug. Different regions of hGH mediate different functions — the 176–191 region drives fat metabolism, while growth promotion and insulin resistance are linked to other regions.

By isolating and modifying this 16-amino acid fragment, researchers created a compound that influences lipolysis and lipogenesis without activating the growth hormone receptor, elevating IGF-1, or causing insulin resistance.

Mechanism of Action

AOD-9604 stimulates lipolysis (breakdown of stored fat) and inhibits lipogenesis (conversion of carbohydrates to stored fat). These are the same metabolic actions of full hGH — but AOD-9604 achieves them through the beta-3 adrenergic receptor pathway on adipocytes, not through the growth hormone receptor.

Preclinical Evidence

In diet-induced obese rodent models, AOD-9604 produced significant reductions in body fat mass — particularly visceral fat — without changes in lean body mass, food intake, or IGF-1 levels. Unlike hGH, it did not cause insulin resistance; some studies noted modest improvements in glucose handling.

The “Fragment Approach”

AOD-9604 exemplifies a broader research strategy: isolating functional fragments from larger molecules. A parallel example is ARA-290 — an 11-amino acid fragment of EPO that retains tissue-protective signaling without stimulating red blood cell production.

Limitations

Despite Phase I safety data from pharmaceutical development, no large-scale human RCTs have been completed. Optimal dosing is undetermined, long-term safety data is unavailable, and the beta-3 mechanism is not fully characterized.

Sources: Ng FM et al. PMID: 10971096; Stierl R et al., Endocrine Society 2003.

Disclaimer: This article is for informational and research purposes only. AOD-9604 is sold as a research peptide and is not FDA-approved for human therapeutic use.