AOD-9604

AOD-9604 is a synthetic fragment of human growth hormone, corresponding to the C-terminal region (residues 176-191) that researchers linked to fat metabolism. Developed by Metabolic Pharmaceuticals in Australia as a potential anti-obesity drug, it was designed to capture the fat-burning action of growth hormone without its growth-promoting or blood-sugar effects.

What is AOD-9604?

AOD-9604 is a 16-amino-acid peptide (sequence YLRIVQCRSVEGSCGF) made up of the last part of the human growth hormone molecule with an added N-terminal tyrosine and a small internal disulfide ring. The name is shorthand for “Anti-Obesity Drug 9604.” It is sometimes written AOD9604 or described as the hGH fragment 176-191 analog. AOD-9604 is not an approved drug; its obesity program was discontinued, and it later appeared as a supplement ingredient and research chemical.

How AOD-9604 is studied to work

The idea behind AOD-9604 is that the fat-metabolizing activity of growth hormone lives in this short C-terminal tail and can be separated from the growth and insulin-like effects that require the whole hormone. Note that the proposed mechanism is drawn largely from animal models.

• Lipolysis and reduced lipogenesis: the fragment is studied for stimulating fat breakdown and inhibiting fat storage, mimicking that action of full growth hormone.
• Beta-3 adrenergic receptor expression: in obese mice it raised repressed beta-3 receptor levels — though the primary study found the lipolytic effect is not directly mediated through that receptor.
• No IGF-1 rise reported: early human studies reported it did not raise serum IGF-1, supporting the idea that it does not act through the growth-hormone-to-IGF-1 axis.
• No reported effect on glucose handling like full growth hormone.

Reported effects and benefits in the research literature

Published findings on AOD-9604 are mixed, and the honest summary is one of early promise that did not hold up:

• Animal fat loss: growth hormone and AOD-9604 reduced body weight and fat in obese mice over two weeks (Heffernan 2001).
• Early human signal: a 12-week trial reported subjects lost on average about 1.8 kg more than placebo.
• Safety/tolerability: across early human trials it was reported as generally safe and well tolerated, with no IGF-1 elevation (Stier 2013).
• Cartilage research: after the obesity work stopped, it was explored for cartilage and osteoarthritis, though a clear positive human outcome is not established.

What this does not mean: the early weight-loss signal was modest and was not confirmed. A larger, longer 24-week trial did not show significant weight loss versus placebo, and obesity-drug development was halted in 2007. Animal receptor findings do not establish a meaningful fat-loss effect in people.

What the human evidence shows

AOD-9604 went through several human trials, including oral phase 2 obesity studies. An earlier study suggested a small weight-loss advantage over placebo, but the pivotal longer trial missed its primary endpoint and the obesity program was discontinued in 2007. AOD-9604 is not FDA-approved for any indication and was never marketed as a pharmaceutical. It was later positioned as a nutraceutical ingredient, and a self-affirmed GRAS (generally recognized as safe) determination has been claimed for food use — a separate and lower regulatory bar than drug approval. In the context of bulk substances for compounding, regulators have flagged AOD-9604 among peptides with limited human safety data. It is also banned in sport.

Handling, storage and reconstitution (research context)

• Lyophilized powder: store cold and dry, protected from light; -20°C for long-term, kept sealed and desiccated.
• Reconstituted solution: refrigerate at 2-8°C, use within a few weeks, avoid repeated freeze-thaw, and protect from light. The disulfide bond makes oxidation a plausible degradation route.
• Concentration math: calculate milligrams per millilitre before reconstituting with the reconstitution calculator; see IU vs mL on why a unit is a volume.
• Compound-specific stability figures are not published; the above are general peptide handling norms.

Cautions and considerations

• AOD-9604 is not an approved drug; its obesity development was discontinued after a failed pivotal trial.
• Supplement/GRAS status is separate from FDA drug approval and does not establish therapeutic efficacy.
• It is banned in competitive sport and tested for.
• Research material purity varies; a Certificate of Analysis should accompany it. This page is informational only and is not medical advice.

Frequently asked questions

Does AOD-9604 actually cause weight loss?

The evidence is weak. An early 12-week trial showed a small advantage over placebo, but the larger pivotal trial did not show significant weight loss, and the obesity program was stopped.

Is AOD-9604 a growth hormone?

No. It is a small fragment of the growth hormone molecule. Unlike full growth hormone, early studies reported it did not raise IGF-1.

Is AOD-9604 FDA-approved?

No. It is not an approved drug. A separate GRAS claim has been made for use as a food ingredient, which is not the same as drug approval.

How does it compare to GH secretagogues?

Secretagogues like ipamorelin or CJC-1295 raise the body’s own growth hormone (and IGF-1). AOD-9604 is instead a fragment studied only for the fat-metabolism action, with no reported IGF-1 rise.

Related compounds and further reading

• How to reconstitute peptides
• Sterile technique
• Tesamorelin
• CJC-1295 (with DAC)
• Ipamorelin
• Browse the full peptide library
• VialHelp guides

For informational use only. Not medical advice; consult a qualified healthcare professional. 21+.