AOD-9604

What is AOD-9604?

AOD-9604 (Anti-Obesity Drug 9604) is a modified fragment of human growth hormone, specifically the last 15 amino acids of the hGH C-terminus (hGH177-191) with a tyrosine addition at the N-terminus. This fragment retains the fat-reducing properties of full-length growth hormone without the anabolic effects (insulin resistance, IGF-1 stimulation) that make prolonged hGH use problematic.

The peptide was developed in the 1990s by Metabolic Pharmaceuticals in Melbourne, Australia, with the goal of creating an anti-obesity drug that captures GH’s lipolytic (fat-burning) properties selectively.

How AOD-9604 Works

AOD-9604’s mechanism is distinct from full-length growth hormone:

• Lipolysis stimulation: Activates β3-adrenergic receptors to stimulate fat breakdown, particularly in adipose tissue
• Lipogenesis inhibition: Reduces the rate at which the body converts food into fat stores
• No IGF-1 stimulation: Unlike full hGH, AOD-9604 does not significantly raise insulin-like growth factor 1 levels
• No glucose intolerance: Does not cause the blood sugar dysregulation associated with hGH use
• Cartilage repair: Preclinical data suggests chondroprotective effects through TGF-beta and proteoglycan synthesis

Research Summary

Obesity and Fat Loss

Multiple Phase 1, 2, and 3 trials in overweight and obese populations were conducted in Australia. Phase 2 results showed statistically significant reduction in body weight versus placebo, particularly in subjects with higher baseline BMI. Phase 3 results were less clear-cut, and Metabolic Pharmaceuticals did not pursue FDA drug approval after Phase 3.

Cartilage and Joint Health

AOD-9604 has been investigated under the name TA-46 for osteoarthritis, with preclinical data suggesting it stimulates cartilage repair through growth factor pathways. Trials for this indication are at earlier stages.

GRAS Status

The 2014 FDA GRAS determination covers AOD-9604 as a food ingredient, which is a relatively unusual regulatory pathway for a peptide. This determination found it safe for consumption at specified doses but does not constitute approval as a drug.

Safety Considerations

• Among the better-studied research peptides, with Phase 2/3 human data
• No serious adverse events in clinical trials
• GRAS status provides additional regulatory validation of safety at specified doses
• Not approved for prescription or OTC therapeutic use as an injectable

Medical Disclaimer: AOD-9604 is not FDA-approved for drug use. This information is for educational purposes only. Do not use peptides without consulting a licensed healthcare provider.

Legal & Regulatory Status

AOD-9604 occupies an unusual regulatory position: FDA GRAS as a food ingredient, but not approved as a pharmaceutical. In the compounding context, it is not on the FDA’s approved bulk substances list. It is available from research peptide vendors and some international compounding pharmacies.

Related Reading

• AOD-9604 (Fragment 176-191): Research, Evidence, and What to Know — Detailed guide to the clinical trial data, dosing research, and limitations of AOD-9604
• GLP-1 Agonists and Muscle Loss: Preserving Lean Mass — How weight-loss peptides compare on body composition outcomes
• Anti-Aging Peptides: What the Research Actually Shows — Broader context for peptides studied in metabolic and longevity applications
• FDA Peptide Status 2026: What’s Legal, What’s Not — Current regulatory landscape for peptides including compounding restrictions
• Peptide Safety: What to Know Before Starting — Foundation guide for evaluating any peptide safely