AOD-9604
A modified fragment of human growth hormone studied in earlier clinical trials; not FDA-approved.
What it is
AOD-9604 is a modified fragment of human growth hormone designed to isolate lipolytic (fat-related) activity without GH's growth effects. It went through real human trials for obesity in the 2000s — and failed to show meaningful weight loss, after which development stopped.
That failed-trial history matters: this is one of the few internet-famous peptides whose weight-loss question was actually tested in controlled human studies, with a negative answer. It later resurfaced through compounding and gray-market channels, marketed as if the trials had gone the other way.
What researchers have actually studied it for
Obesity, in completed human trials that did not demonstrate meaningful weight loss; development was discontinued.
How it works
The hGH 177-191 tail region with a stabilizing tyrosine — designed to trigger fat-cell lipolysis via beta-3-adrenergic-linked pathways without touching the GH receptor's growth signaling or IGF-1. The design goal succeeded; the clinical effect didn't follow.
The molecule itself
hGH's C-terminal 177-191 fragment with an added N-terminal tyrosine for stability — a 16-residue excerpt of the 191-residue hormone, designed to keep lipolytic signaling while abandoning the GH receptor and IGF-1 axis entirely. The design succeeded pharmacologically; the clinic result didn't follow.
Where it came from
Developed by Australian company Metabolic Pharmaceuticals from Monash University fragment research, AOD-9604 ran a full obesity program in the early 2000s. Phase 2b showed no meaningful weight-loss separation from placebo, development ended around 2007, and the molecule reappeared later in anti-obesity marketing that skips that chapter.
The timeline
1990s
Monash University fragment research maps hGH's lipolytic region.
early 2000s
Metabolic Pharmaceuticals runs the human obesity program.
~2007
Phase 2b shows no meaningful weight loss vs placebo; development ends.
2010s
US GRAS food-ingredient status obtained — a regulatory oddity.
2010s+
Compounding and gray markets revive it, minus the trial results.
What the research record actually contains
- Multiple human trials, including a 300-patient phase 2b in obesity: no significant weight loss versus placebo.
- Good tolerability and no IGF-1 elevation across the program — the genuinely positive findings.
- Assorted animal work on cartilage and metabolism since; no human revival of efficacy.
What could change this assessment
Occasional academic threads (cartilage models) persist without momentum. Its honest role now is educational: the clearest demonstration that plausible mechanisms fail human trials all the time — which is why trials exist.
What's known about risks
Unusually for this library, real trial safety data exists: well tolerated, no growth-axis activation. Its clinical history makes it more safety-characterized and less efficacious than almost anything else sold beside it.
Where it stands legally
Never approved; appears in compounding and gray-market channels, with eligibility the usual moving-target question. It has held US GRAS status as a food ingredient — a regulatory oddity that says nothing about efficacy.
Worth asking a licensed provider
- 1.Are you aware its human obesity trials failed — and what would justify using it anyway?
- 2.If fat loss is the goal, why not the GLP-1 class, where the evidence actually exists?
- 3.What would we measure to know it was doing anything at all?
Common claims, corrected
“It's the fat-loss part of growth hormone.”
Reality: That was the hypothesis; its own trials falsified the useful version of it. It's the rare compound sold against its own completed evidence.
“GRAS status means FDA endorsed it.”
Reality: GRAS is a food-ingredient safety pathway — nothing to do with efficacy or drug approval, and mostly a testament to its benign uselessness at tested doses.
AOD-9604 FAQ
Does AOD-9604 work for fat loss?
Its own clinical trials — real, controlled, human — did not show meaningful weight loss versus placebo, and the program was abandoned. It is the rare case where the marketing question has a tested answer, and the answer was no.
Is AOD-9604 safe?
The trials reported reasonable tolerability, which is the one genuinely positive thing its clinical history offers. Safety of long-term unsupervised use from unregulated sources is a different, unanswered question.
Why is AOD-9604 still sold?
Because the fragment's origin story — 'the fat-loss part of growth hormone' — is a better pitch than its trial results. Few buyers read phase 2 outcomes.
How badly did the trials fail?
The phase 2b — around 300 patients — found no significant weight-loss separation from placebo, and the sponsor discontinued. Not ambiguous, not underpowered folklore: a run test with a null answer.
Why does anything still sell it?
Because the origin story outsells the outcome data, and few buyers read phase 2 results. Its market is a monument to unread endpoints.