AOD-9604

Growth hormone has fat-reducing effects, but its long-term use is limited by effects such as raised IGF-1, insulin resistance and impaired glucose tolerance ^[4]. In the 1990s, researchers at Monash University in Melbourne studied fragments of the hormone’s tail (the C-terminal end) that seemed to carry the fat-reducing activity. AOD-9604 is a synthetic version of amino acids 177 to 191 of human growth hormone with an extra tyrosine at the start, giving 16 amino acids in total ^{[6] [7]}.

It was developed by the Australian company Metabolic Pharmaceuticals as an oral anti-obesity drug ^[3]. Today it is sold online as an injectable research peptide and marketed by some clinics for weight loss, which is not how it was tested in trials. It is often grouped with growth hormone secretagogues such as ipamorelin and CJC-1295, but it works differently: it does not stimulate growth hormone release. See what research peptides are.

AOD-9604 is proposed to mimic growth hormone’s effect on fat metabolism, increasing the breakdown of stored fat (lipolysis) without its effects on growth or blood sugar. In a 2001 mouse study, both growth hormone and AOD-9604 reduced body weight and fat over 14 days and increased expression of the beta-3 adrenergic receptor in fat. In mice lacking that receptor, long-term treatment did not reduce weight, though a single dose still increased fat oxidation, so the authors concluded the effect was not simply mediated through that receptor ^[2].

In the company’s human studies, AOD-9604 did not raise IGF-1 levels, which is consistent with the idea that it lacks growth hormone’s growth-promoting effects ^{[4] [6]}.

The animal evidence is from rodents and one rabbit study. In obese Zucker rats, oral AOD-9604 at 500 µg/kg per day for 19 days roughly halved body weight gain compared with controls, increased fat-tissue lipolysis and, unlike intact growth hormone, did not worsen insulin sensitivity ^[1]. The mouse study above found reduced weight and fat over two weeks of injections ^[2].

A 2015 study in rabbits with chemically induced knee osteoarthritis reported that injections of AOD-9604 into the joint, particularly with hyaluronic acid, improved cartilage scores and shortened lameness ^[8]. This has not been tested in people.

Metabolic Pharmaceuticals ran six randomised, double-blind, placebo-controlled trials, summarised in a 2013 paper written by people employed by or consulting for the company ^[4]. Early small studies gave AOD-9604 intravenously (single doses in groups of 15 and 23 men) or by mouth (short studies in 16 to 36 men). A 2004 review of these early studies, as summarised by the FDA in 2024, reported no statistically significant weight loss compared with placebo ^{[3] [6]}.

A 12-week trial in 300 people with obesity was reported only as a conference abstract; the authors described greater weight loss than placebo at all doses, but the FDA noted the differences were small and few details were given ^[6]. The largest trial, the phase 2b OPTIONS study, randomised 502 of 536 enrolled adults with obesity to oral AOD-9604 0.25 mg, 0.5 mg or 1 mg daily, or placebo, for 24 weeks alongside diet and exercise. It found no significant difference in weight loss at 12 weeks, the primary end point. In February 2007 the company announced that the results did not support commercial viability and ended development for obesity ^[6].

According to the FDA, no study of AOD-9604 given by subcutaneous injection, the way it is now usually sold for, has been published ^[6].

In humans, the company trials used intravenous single doses of 25 to 400 µg/kg, oral doses of 9 to 54 mg in short studies, and oral daily doses of 1 to 30 mg for 12 weeks and 0.25 to 1 mg for 24 weeks ^[6]. The largest of these trials found no significant difference from placebo in weight loss, and none tested injection under the skin. The rat study used 500 µg/kg by mouth daily ^[1].

These doses are reported for information only and are not a recommendation. Animal doses should not be converted into human doses.

The company’s summary of its six trials described AOD-9604 as well tolerated, with adverse events similar to placebo and no rise in IGF-1, no effect on glucose tolerance and no antibodies against the peptide in the patients tested ^[4]. Headache was the most common complaint with intravenous dosing, and headache, diarrhoea and flatulence with oral dosing ^[6].

The FDA’s reviewers were more cautious. They noted that the summaries lacked detail, that several cancers (including breast cancer and melanoma) were reported in the 12-week oral study and judged unrelated by the investigators, and that the information was insufficient to confirm this. They also raised concerns about immunogenicity and aggregation for injectable forms, and noted that no safety data exist for injection under the skin ^[6]. A 2026 review of peptides marketed in sports medicine, including AOD-9604, found rigorous human safety data scarce ^[10].

AOD-9604 is not an approved medicine in the US, UK, EU, Canada, Australia or New Zealand. In the US, it was nominated for the list of substances pharmacies may use in compounding. At its December 2024 meeting, the FDA’s Pharmacy Compounding Advisory Committee voted 12 to 0 against adding it to that list, in line with the FDA’s proposal ^{[5] [6]}. The FDA’s briefing also noted that Australia placed AOD-9604 in its poisons standard as a performance and image enhancing drug, making possession without authority illegal there ^[6]. See our legal status pages and the Australia page for detail.

In sport, AOD-9604 has been named as an example of a prohibited growth hormone fragment on the WADA Prohibited List since the 2018 list, under section S2, and is prohibited at all times ^[9]. Anti-doping laboratories have published methods to detect it in urine ^[7].

AOD-9604 is sold as a freeze-dried powder. The FDA noted that its disulfide bond can be broken down and that the peptide can aggregate ^[6], so careful storage matters: keep it cold, dry and dark, and refrigerate after reconstitution. See how to store peptides.

PepFinder does not sell AOD-9604. You can compare prices, read how to read a COA, and see which vendors have third-party tested batches.