AOD-9604
Also known as: Growth-hormone fragment analogue
Developed as an anti-obesity drug and tested in humans — where it failed to beat placebo for weight loss, despite being resold today as a fat-loss peptide.
What it is
AOD-9604 is a synthetic fragment based on part of the growth-hormone molecule, originally developed by a pharmaceutical company as a potential anti-obesity treatment. It is unusual in this space because it was actually tested in humans.
Composition
It corresponds to a small fragment of the growth-hormone molecule, related in concept to other "fat-loss" growth-hormone fragments. What is sold online is a research chemical.
Proposed mechanism
It was proposed to stimulate fat breakdown without the broader growth-hormone effects on blood sugar — the rationale for developing it as a weight-loss drug.
Claimed benefits
Targeted fat loss without the downsides of growth hormone.
What the evidence shows
Not supported· human data. This is the unusual case where the compound was properly tested: in human clinical trials for obesity, it did not produce significantly more weight loss than placebo, and development for that use did not succeed. The fat-loss claims now made for it are contradicted by the very trials meant to prove them.
Legal & regulatory status
It is a non-approved substance. That places it in a prohibited category under WADA rules, and anti-doping authorities have treated it as banned; athletes should regard it as prohibited.
Known risks & unknowns
In the obesity trials it was reasonably tolerated, but "didn't clearly harm" is not the same as "works", and long-term safety for the way it is used today is not established. Research-chemical products also carry purity and contamination risks.
Sources
Frequently asked questions
- What is AOD-9604?
- It is a synthetic fragment based on part of the growth-hormone molecule, originally developed by a pharmaceutical company as a potential anti-obesity treatment. It is closely related in concept to other 'fat-loss' growth-hormone fragments.
- Does AOD-9604 cause fat loss?
- This is the unusual case where it was actually tested: in human clinical trials for obesity, it did not produce significantly more weight loss than placebo, and development for that use did not succeed. So the fat-loss claims now made for it are contradicted by the very trials meant to prove them.
- Is AOD-9604 safe?
- In the obesity trials it was reasonably tolerated, but 'didn't clearly harm' is not the same as 'works', and long-term safety for the way it is used today is not established. Research-chemical products also carry purity and contamination risks.
- Is AOD-9604 banned in sport?
- It is a non-approved substance, which places it in a prohibited category under WADA rules, and anti-doping authorities have treated it as banned. Athletes should regard it as prohibited.
Related compounds
- HGH Fragment 176-191 — Marketing claim
An evidence-tiered explainer on HGH Fragment 176-191 / AOD-9604: a growth-hormone fragment marketed for fat loss whose largest human trial failed, leading its developer to abandon it.
- GLP-1 receptor agonists — Well-supported
How GLP-1 receptor agonists (semaglutide, tirzepatide) differ from the unregulated 'research peptides': real large-scale trials, regulatory approval, and prescription-only status.
Written and reviewed by Mathew Beale — MSc Biotechnology, University of Reading.
Last reviewed: