Last updated 18 September 2026 · SARMs Store editorial team. Products on this site are supplied strictly for laboratory research and are not for human consumption. This guide summarises published research; it is not medical advice and contains no instructions for use. 18+ only.
HGH Fragment 176-191 at a glance
| Class | Synthetic fragment of human growth hormone, amino acids 176 to 191 (as AOD9604, with a tyrosine added) |
|---|---|
| Developed by | Monash University and Metabolic Pharmaceuticals, Australia, 1990s to 2007 |
| Highest evidence | Phase II human trials in obesity (did not meet endpoints; programme stopped 2007) |
| Studied for | Fat metabolism without the growth or insulin effects of full growth hormone |
| Format | Lyophilised vial (5mg) |
| Storage | 2 to 8°C unopened, frozen long term |
| UK status 2026 | Research chemical; not a licensed medicine; WADA S2 |
What HGH Fragment 176-191 is
HGH Fragment 176-191 is the C-terminal tail of human growth hormone, the sixteen amino acids at the end of the 191-residue hormone. Researchers at Monash University proposed in the 1990s that this region carried the fat-metabolising activity of growth hormone without its effects on growth, IGF-1 or blood sugar. A stabilised version with an extra tyrosine, coded AOD9604, was taken into clinical development by Metabolic Pharmaceuticals. The material sold for research is the fragment or AOD9604; product listings should say which.
What the research found
Animal work. Studies in obese mice and rats in the late 1990s and early 2000s (Heffernan and colleagues; Ng and colleagues) reported reduced body fat and increased fat oxidation without the rise in IGF-1 or insulin resistance seen with full growth hormone. These are the studies behind every claim made for the fragment.
Human trials. Metabolic Pharmaceuticals ran phase I and phase II trials of oral AOD9604 in obese adults between 2001 and 2007, with several hundred participants. The compound was well tolerated, but the phase IIb trials did not show a meaningful difference in weight loss against placebo, and the company stopped development in 2007. This is the most important fact about the fragment: it has more human safety data than most research peptides and a negative efficacy result.
After 2007. AOD9604 later received GRAS (generally recognised as safe) status in the United States as a food ingredient at low doses, and has been studied in small trials for cartilage and joint applications. None of that reverses the obesity result.
Stability, storage and handling
Supplied lyophilised in a sealed vial. Keep unopened vials at 2 to 8 degrees Celsius or frozen for long storage, away from light. Reconstituted solutions degrade over days to weeks. The certificate should show HPLC purity and mass spectrometry identity.
Legal status in the UK, 2026
Not a controlled substance under the Misuse of Drugs Act 1971. Not a licensed medicine in the UK, so it cannot be sold or advertised for human use; supplied strictly for laboratory research. In sport it is prohibited at all times under WADA section S2, and AOD9604 was named in a high-profile Australian sports supplements case in 2013.
What to check before buying
Milligrams per vial, HPLC purity, mass spectrometry identity, a batch number matching the certificate, and cold-chain shipping. Every Origin Peptides batch is independently tested and its certificate of analysis is published on the product page and the Lab Testing page.
Frequently asked questions
Is HGH Fragment 176-191 the same as AOD9604?
Almost. AOD9604 is the fragment with an added tyrosine for stability. Listings should state which is supplied.
Did the human trials work?
The phase II obesity trials did not meet their endpoints and the programme was stopped in 2007.
Does it raise IGF-1?
In the animal and human studies, no. That was the design goal.
Is it legal in the UK?
Legal to buy and possess as a research compound; not lawful to sell or advertise for human consumption; banned in sport.
Key references
Heffernan M, Summers RJ, Thorburn A, et al. The effects of human GH and its lipolytic fragment (AOD9604) on lipid metabolism following chronic treatment in obese mice and beta3-AR knock-out mice. Endocrinology. 2001;142(12):5182-5189. Ng FM, Sun J, Sharma L, Libinaki R, Jiang WJ, Gianello R. Metabolic studies of a synthetic lipolytic domain (AOD9604) of human growth hormone. Hormone Research. 2000;53(6):274-278. Metabolic Pharmaceuticals, AOD9604 phase IIb results, company announcements 2007. World Anti-Doping Agency. Prohibited List 2026, section S2.
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Research products: Origin Peptides HGH Fragment 176-191 5mg · 5-Amino-1MQ · NAD+ · Full Origin Peptides range · Lab Testing