AOD 9604 Benefits and Side Effects: Research Data
What AOD-9604 did in animal fat-metabolism studies, what its human obesity trials found, the side effects FDA recorded, and how it relates to hGH fragment 176-191.
Update History ▾
Research-use-only framing applied throughout in line with Remy editorial standards.
AOD 9604 benefits come mainly from early research in animal models: in obese rats and mice this modified fragment of human growth hormone (hGH) reduced weight gain and increased fat breakdown and fat oxidation.[1][2] In people, the fat loss and weight management claims did not hold up. FDA’s 2024 review records that the largest trial, a 24-week study in 536 enrolled adults with obesity, found no significant weight loss compared with placebo, and the developer ended development for obesity in 2007.[3]
Across six human trials the reported side effects were mostly headache and mild gut symptoms, and IGF-1 levels did not change.[3] AOD-9604 is not FDA approved, and WADA lists it as a prohibited growth hormone fragment.[4][5] Remy Research supplies AOD-9604 and hGH fragment 176-191 for in-vitro laboratory research only.
What Is AOD-9604? A Modified Fragment of Human Growth Hormone
AOD-9604 is a synthetic peptide derived from the C-terminal region of human growth hormone (hGH). FDA describes it as a hexadecapeptide: residues 177–191 of hGH with an additional tyrosine at the N-terminal end, 16 amino acids in all.[3] The original papers called it a synthetic lipolytic domain of hGH, because this tail of the hormone was linked to fat breakdown.[1] It was originally developed by Metabolic Pharmaceuticals as an obesity drug.[3]
AOD-9604 is not full growth hormone. In laboratory tests it did not compete for the hGH receptor and did not induce cell proliferation, which set it apart from the full-length hormone.[2] For the full development history, see the AOD-9604 research review.
How AOD-9604 Targets Fat Metabolism
In obese mice, both full growth hormone (human growth hormone, hGH) and AOD-9604 reduced body weight and body fat after 14 days and raised the expression of beta-3 adrenergic receptor RNA in adipose tissue. Mice lacking that receptor did not lose weight on long-term treatment, yet AOD-9604 still increased energy expenditure and fat oxidation in short experiments, so the authors concluded its lipolytic action is not mediated directly through the beta-3 receptor.[6]
FDA’s reviewers reached a similar point in 2024: nonclinical studies suggest that stimulating lipolysis, the breakdown of stored fat, depends at least in part on intact beta-3 adrenergic signalling, but the molecular target and the mechanism of action remain unknown.[3]
AOD 9604 Benefits: Potential Benefits Studied
| Claimed benefit | What was reported | Evidence type |
|---|---|---|
| Less weight gain | Body weight gain cut by more than half in obese Zucker rats | Animal |
| Fat oxidation | More fat oxidation and lipolysis markers in obese mice | Animal |
| Blood sugar | No high blood sugar or reduced insulin secretion in mice | Animal |
| Cartilage | Lower cartilage damage scores in a rabbit knee model | Animal |
| Weight loss | 24-week trial: no significant difference from placebo | Human trial negative |
| IGF-1 levels | No significant change versus placebo | Human trials |
Fat Loss, Body Weight and Lipid Metabolism in Animal Models
In obese Zucker rats, daily AOD-9604 by mouth for 19 days cut body weight gain by more than 50% compared with controls, and adipose tissue from treated rats showed higher lipolytic activity.[1] In obese mice, AOD-9604 and hGH both reduced weight gain over 14 days, together with higher fat oxidation and higher plasma glycerol, an index of fat breakdown.[2] These metabolic studies are the source of the fat loss, fat burning and body composition claims made for AOD-9604. They were short preclinical research in rodents, and none measured lean mass or fat mass in people.
Blood Sugar, Insulin Sensitivity and IGF-1
Full growth hormone can raise blood sugar. In the obese mouse study, hGH did; AOD-9604 did not cause hyperglycaemia or reduce insulin secretion.[2] In the rat study, unlike intact hGH, chronic AOD-9604 had no adverse effect on insulin sensitivity measured by euglycaemic clamp.[1] In human trials, FDA’s review found no statistically significant differences in IGF-1 levels between AOD-9604 groups and placebo.[3]
Cartilage in a Rabbit Osteoarthritis Model
In 32 rabbits with chemically induced knee osteoarthritis, AOD-9604 given into the joint, alone or with hyaluronic acid, gave lower cartilage degeneration scores than saline, and the combination worked best.[7] No human cartilage study has been published.
Human Clinical Trials: What the Obesity Programme Found
FDA’s briefing lists six human clinical trials, METAOD001 to METAOD006. Four were small: two single-dose intravenous studies in 15 and 23 men and two oral studies in 17 and 36 men with obesity. Two were larger controlled human trials of an oral formulation: a 12-week study in 300 men and women with obesity and the 24-week OPTIONS study, which enrolled 536 and randomised 502 adults aged 18 to 65.[3]
In OPTIONS, weight loss compared with placebo at 12 and 24 weeks was too low to reach statistical significance. On February 21, 2007 the company announced that the results did not support the commercial viability of AOD-9604 for obesity and that development for that condition was terminated.[3] That is the current evidence on weight management in people: a negative trial, not a positive one.
AOD-9604 Side Effects and Safety Data
The human safety record comes from the six trials, summarised by FDA in 2024.[3]
- Single-dose intravenous studies. Headache was the most frequent event, followed by fatigue, low blood sugar, dizziness, sore throat and cough; most headaches were mild or moderate.[3]
- Oral studies. Reported events included headache, diarrhoea, flatulence, increased appetite and nausea, and in the larger trials nasopharyngitis and back pain.[3]
- Serious adverse events. FDA’s briefing lists diarrhoea and pneumonia in one small study, and basal cell carcinoma, lipoma, squamous cell carcinoma, breast cancer and malignant melanoma in AOD-9604 groups of the 12-week trial.[3]
- IGF-1 and antibodies. IGF-1 did not differ significantly from placebo, and no antibodies against the peptide were detected in the subjects tested.[3]
- Animal toxicology. In rats and monkeys, FDA noted changes in blood urea, creatinine, triglycerides and osteocalcin, lower liver weight and glycogen in male monkeys, and genotoxicity tests with equivocal signals.[3]
The longest human trial lasted 24 weeks, so there are no long-term human safety data.[3] These findings come from controlled trials of a pharmaceutical product, not from research-grade material.
Is AOD-9604 FDA Approved? Regulatory Status and Peptide Therapy Compounding
- FDA approval. No. AOD-9604 has never received regulatory approval; its obesity development ended in 2007.[3]
- Compounding. On December 4, 2024 FDA’s Pharmacy Compounding Advisory Committee voted 0 yes, 12 no on adding AOD-9604 to the 503A bulks list.[4] FDA’s Category 2 page lists AOD-9604 among bulk drug substances nominated but withdrawn.[8]
- Sport. WADA’s 2027 Prohibited List names growth hormone fragments, for example AOD-9604 and hGH 176-191, under S2.[5]
- UAE. Remy Research sells AOD-9604 for in-vitro laboratory research only, not for human or veterinary use.
AOD-9604 vs Full HGH and hGH Fragment 176-191
Compared with full-length hGH, AOD-9604 behaved differently in the same obese mouse study. Both reduced body weight gain and raised fat oxidation, but only full hGH caused hyperglycaemia and reduced insulin secretion. AOD-9604 showed no receptor binding at the hGH receptor and did not stimulate cell proliferation, which the authors read as action through a pathway distinct from traditional hGH signalling.[2]
AOD-9604 and hGH fragment 176-191 are often used as if they were the same compound. They are related but not identical. hGH fragment 176-191 is the last 16 residues of the hormone itself, listed in PubChem as somatotropin (176-191).[9] AOD-9604 is a modified form: the 177–191 tail of hGH with a tyrosine added at the front.[3]
The obese rodent studies and the whole human trial programme used AOD-9604, so their results should not be read as data on the unmodified fragment.[1][6][3] WADA names AOD-9604 and hGH 176-191 separately as examples of growth hormone fragments.[5] See AOD-9604 vs hGH fragment 176-191 and the HGH Fragment 176-191 research article. For a growth hormone peptide from a different class, see tesamorelin, a GHRH analog.
What AOD-9604 Research Does Not Yet Show
- Weight loss in people. The largest trial did not show significant weight loss versus placebo.[3]
- A defined mechanism. FDA states the molecular target remains unknown.[3]
- Joint benefits in people. Cartilage data come from one rabbit study.[7]
- Long-term safety. No human trial lasted longer than 24 weeks.[3]
AOD-9604 for Laboratory Research
Remy Research supplies AOD-9604 for in-vitro research as the AOD-9604 10mg vial and the Genovare AOD-9604 25mg AQ pen, hGH fragment 176-191 as the Genovare HGH Fragment 176-191 25mg AQ pen, and both together as the Genovare HGH Fragment 176-191 + AOD-9604 50mg AQ pen. Each product page carries its batch testing details. For formats and UAE availability, see the AOD-9604 UAE research guide.
Our Research Standards
This article prioritizes primary literature and FDA advisory committee records, and keeps animal and human evidence apart. The negative human trial is reported alongside the positive animal findings. No therapeutic, dosing or administration guidance is given. Read our editorial policy →
AOD-9604 Benefits and Side Effects FAQ
What are the benefits of AOD-9604?
What are the side effects of AOD-9604?
In human trials the most frequent events were headache, fatigue, dizziness, diarrhoea, flatulence, increased appetite and nausea. IGF-1 did not change and no antibodies were detected.[3]
Is AOD-9604 FDA approved?
Is AOD-9604 safe?
Trials up to 24 weeks reported mostly mild events, but FDA also listed serious adverse events and equivocal genotoxicity signals. There are no long-term human data, and no data on research-grade material.[3]
Is AOD-9604 the same as hGH fragment 176-191?
Does AOD-9604 raise IGF-1 like HGH?
Does AOD-9604 affect blood sugar?
Is AOD-9604 banned in sports?
Yes. The WADA 2027 Prohibited List names AOD-9604 and hGH 176-191 as growth hormone fragments under S2.[5]
Sources
- Ng FM, Sun J, Sharma L, Libinaka R, Jiang WJ, Gianello R. Metabolic studies of a synthetic lipolytic domain (AOD9604) of human growth hormone. Horm Res. 2000;53(6):274-278. doi: 10.1159/000053183 · PMID: 11146367 ↩
- Heffernan MA, Thorburn AW, Fam B, et al. Increase of fat oxidation and weight loss in obese mice caused by chronic treatment with human growth hormone or a modified C-terminal fragment. Int J Obes Relat Metab Disord. 2001;25(10):1442-1449. doi: 10.1038/sj.ijo.0801740 · PMID: 11673763 ↩
- U.S. Food and Drug Administration. Pharmacy Compounding Advisory Committee meeting, December 4, 2024: briefing document for AOD-9604 (identity, nonclinical toxicology, human trials METAOD001–006, adverse events), checked October 28, 2026. fda.gov/media/183584 ↩
- U.S. Food and Drug Administration. Pharmacy Compounding Advisory Committee meeting, December 4, 2024: summary minutes (AOD-9604 free base and acetate: 0 yes, 12 no, 0 abstain). fda.gov/media/185642 ↩
- World Anti-Doping Agency. The 2027 Prohibited List (in force January 1, 2027); S2 names growth hormone fragments, e.g. AOD-9604 and hGH 176-191. wada-ama.org ↩
- 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 beta(3)-AR knock-out mice. Endocrinology. 2001;142(12):5182-5189. doi: 10.1210/endo.142.12.8522 · PMID: 11713213 ↩
- Kwon DR, Park GY. Effect of intra-articular injection of AOD9604 with or without hyaluronic acid in rabbit osteoarthritis model. Ann Clin Lab Sci. 2015;45(4):426-432. PMID: 26275694 ↩
- U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding that May Present Significant Safety Risks (Category 2 page, modified April 22, 2026; AOD-9604 listed under bulk drug substances nominated but withdrawn), checked October 28, 2026. fda.gov ↩
- National Center for Biotechnology Information. PubChem Compound Summary for CID 16131230, Somatotropin (176-191) (C78H123N23O22S2, 1799.1 g/mol), checked October 28, 2026. pubchem.ncbi.nlm.nih.gov/compound/16131230 ↩
For catalog details, see the AOD-9604 10mg vial, the Genovare AOD-9604 25mg AQ pen, the Genovare HGH Fragment 176-191 25mg AQ pen and the Genovare HGH Fragment 176-191 + AOD-9604 50mg AQ pen. For editorial standards, continue to the editorial policy.