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Not medical advice. The Atlas is not a substitute for a clinician who can examine you.

AOD-9604

HGH Fragment 176-191

Evidence grade 1 of 5, Untested. Read how the Atlas grades evidence.

The claimed use, weight loss in obesity, is best read as refuted at scale. An early 12-week dose-ranging study (Thompson/Ng et al., Obesity Research 2007, ~300 subjects) reported a modest signal at the 1 mg dose, roughly 2.6 kg loss versus 0.8 kg on placebo, but the larger, adequately powered 24-week Phase 2b confirmatory trial (METAOD006 / OPTIONS, 536 subjects) failed to reach its primary weight-loss endpoint versus placebo, and Metabolic Pharmaceuticals halted the obesity drug program in 2007. Later human data support only a favorable short-term safety and tolerability profile, not efficacy, so the weight-loss indication is graded 1.

FDA
Not FDA approved; no New Drug Application filed and no approval letter for any use. Industry expert-panel GRAS self-affirmation exists for limited food-ingredient use only, which is not FDA endorsement and does not cover drug or compounded use. Removed from Category 2 of the FDA interim 503A compounding bulks list on September 27, 2024 and referred to the Pharmacy Compounding Advisory Committee.
WADA
Prohibited

Reference only. Not medical advice.

What can go wrong

Failed its pivotal Phase 2b obesity trial and was discontinued in 2007; no proven weight-loss efficacy; not FDA approved and not on the FDA 503A compounding bulks list; WADA prohibited in sport.

Talk to a clinician before taking this. The Atlas can tell you what has been studied about AOD-9604. It cannot tell you how it would interact with your body, your history, or anything else you are taking, and nothing on this page is a reason to start.

A fragment of human growth hormone spanning the 176-191 region, associated in preclinical work with fat metabolism without the growth-promoting or muscle effects of full-length HGH. Developed from research at Monash University in Australia by Metabolic Pharmaceuticals. An early 12-week trial showed a modest weight-loss signal, but the larger 24-week Phase 2b obesity trial did not reach its primary endpoint versus placebo, and drug development was halted in 2007. It is not FDA approved and remains popular in research-chemical body-composition marketing that overstates the evidence.

The fat-burning fragment of HGH, no muscle effect. Australian origin. Failed its obesity trial.

What people take it for

These are the reasons people give for taking it. They are not effects it has been shown to have.

  • Body fat reduction
  • Metabolic health
  • Weight management

How it is supposed to work

AOD-9604 is the tail end of the growth-hormone molecule, the small piece responsible for burning fat, isolated and used on its own. The idea was to capture growth hormone’s fat-burning effect while leaving behind the parts that build muscle, raise blood sugar and drive growth. It stimulates the breakdown of stored fat and discourages new fat formation, acting directly on fat tissue without raising IGF-1 or disturbing glucose control, and without signaling the pituitary the way the full hormone does.

AOD-9604 is a synthetic 16-amino-acid peptide corresponding to the C-terminal fragment of human growth hormone (amino acids 176-191) with an extra tyrosine added at the front, hence its other name, Tyr-hGH 177-191. It was developed in the 1990s by Metabolic Pharmaceuticals in Australia, with roots in Monash University research, and its name literally stands for Advanced Obesity Drug-9604, a reminder of exactly what it was built and tested to be.

Type
HGH fragment (176-191)
Size
16 amino acids
Action
Lipolysis, no IGF-1 effect
Obesity program
Terminated 2007
Approved
No
WADA
Prohibited

A Fat-Loss Peptide That Failed Its Fat-Loss Trials

AOD-9604 is a clean illustration of marketing outliving evidence. The pitch is appealing, growth hormone’s fat-burning without its downsides, and the mechanism is real. But the decisive fact the marketing buries is that AOD-9604 failed as an obesity drug, on its own terms. Across six clinical trials and more than 900 participants, its best result was modest, around a couple of kilograms more than placebo, its largest Phase IIb trial missed statistical significance, and its developer terminated the obesity program in 2007 because it was not a viable weight-loss medicine. It is nowhere near the efficacy class of the GLP-1 drugs people now compare it to. Its one genuine strength is an unusually large safety database showing it is well tolerated, which is worth crediting, but being safe is not the same as working, and it is still sold as a fat-loss peptide two decades after failing as one.

Safety in detail

Human trials associated AOD-9604 with a generally clean short-term safety and tolerability profile, including no reported increase in IGF-1 or worsening of glucose tolerance, but that safety signal does not establish efficacy. The FDA has flagged concerns about immunogenicity, peptide-related impurities, and limited safety information for compounded use. Marketed oral and injectable research-chemical products are typically labeled not for human consumption.

  • Its safety is unusually well documented for a peptide, with more than 900 participants across six controlled trials showing it is well tolerated.
  • By design it does not raise IGF-1, does not impair glucose control, and does not produce growth-hormone-like growth effects.
  • The central problem is efficacy, not safety: it simply did not work well enough as a weight-loss drug.
  • It is prohibited in sport as a growth-hormone fragment.
  • Long-term data is limited, and gray-market or compounded product carries the usual quality caveats.

Children and teenagers

AOD-9604 is a fat-loss peptide with no pediatric indication and no place in anyone under 18. Weight management in children and adolescents belongs with qualified pediatric specialists, not gray-market peptides, and that is doubly true for a compound whose weight-loss efficacy failed in adults. There is no appropriate pediatric use.

What people get wrong

Nothing recorded here yet. There is almost certainly something people get wrong about this one, and the blank space means we have not written it down, not that the record is clean.

Who profits, and who pushes back

Nobody is named here yet, because we have not done that work on this entry. Read that as unfinished. Somebody almost certainly sells this, and somebody almost certainly disputes it. Assume both until we have checked.

AOD-9604’s money now flows through channels that outlived its failed drug development: gray-market peptide vendors, compounding pharmacies, supplement sellers (it carried a food-ingredient safety claim at one point), and weight-loss and wellness clinics. The original developer, Metabolic Pharmaceuticals, terminated the obesity program and looked to license it for other uses. The result is a compound marketed for fat loss by a marketplace that has moved past the inconvenient fact that its obesity trials did not succeed.

How we got here

AOD-9604 is a modified analogue of the HGH 176-191 fragment, developed by Metabolic Pharmaceuticals Ltd. from research at Monash University in Australia, with an added N-terminal tyrosine residue for stability. It advanced through six Phase I/II human clinical trials for obesity but was discontinued after failing to show statistically significant weight loss versus placebo at its primary endpoint. It was later self-affirmed as GRAS (Generally Recognized as Safe) as a food ingredient rather than approved as a pharmaceutical drug.

AOD-9604 came from work isolating the fat-burning fragment of growth hormone, developed in the 1990s by Metabolic Pharmaceuticals in Australia with Monash University roots. Promising animal results and early human data led to a substantial clinical program, six trials in more than 900 people. But the largest Phase IIb trial missed statistical significance, and the company terminated obesity development in 2007. The molecule was then repositioned toward supplement and joint-health uses, and over the following years it persisted in the gray market and compounding world as a fat-loss peptide, even as the GLP-1 era made its modest, failed numbers look weaker still.

  1. 1990sMetabolic Pharmaceuticals develops AOD-9604 as an isolated fat-burning growth-hormone fragment.
  2. 2000sSix clinical trials in 900+ people; a 12-week study shows only modest weight loss.
  3. 2007The largest Phase IIb trial fails; obesity development is terminated.
  4. 2010sRepositioned toward supplement and joint-health uses; persists in gray-market fat-loss circles.
  5. 2020sGLP-1 drugs reset weight-loss expectations; AOD-9604 remains unapproved and restricted.

The numbers behind the grade

Type
HGH fragment (176-191)
Action
Fat metabolism
Obesity trials
Failed
Terminated
2007
Approved
No
WADA
Prohibited

The people taking it

A long-circulating, heavily marketed fat-loss peptide and one of the most debated compounds in the field, sold for two decades despite its obesity program having failed.

AOD-9604’s users are overwhelmingly weight- and fat-loss seekers drawn by the promise of fat burning without growth-hormone side effects, plus bodybuilders using it while cutting, wellness-clinic patients, and a smaller group interested in joint and cartilage health. Many are people looking for an alternative or adjunct to GLP-1 drugs, often unaware that AOD-9604’s own weight-loss trials failed.

Marketed and used gray-market, compounded and as a supplement for fat loss and joint health; not approved, banned in sport, and far weaker than GLP-1 drugs for weight loss.

Set against the alternatives

The comparison that matters is to the modern GLP-1 and GIP drugs, because that is how AOD-9604 is often marketed, and it is not close. Semaglutide and tirzepatide produce double-digit percentage weight loss backed by large successful trials; AOD-9604’s best result was a couple of kilograms, and its trials failed, so it should not be positioned as a peer. Against full growth hormone, AOD-9604 did achieve its design goal of isolating the fat-burning effect without the IGF-1, glucose and growth effects, a real mechanistic success, but one that did not translate into meaningful clinical weight loss. Its mechanism is legitimate; its efficacy is the problem.

What we do not know

  • Whether AOD-9604 produces any meaningful weight effect in practice, given that its trials failed.
  • Whether its cartilage and joint-health uses have genuine merit.
  • Why it persists in the market two decades after its obesity program ended.
  • How it performs against GLP-1 drugs head to head, where the evidence strongly favors the latter.

What could change

Compounding accessEvolving rules may reopen a compounding pathway, as with other peptides.The GLP-1 contrastModern weight-loss drugs make its failed, modest numbers look weaker still.Joint and cartilage useA niche research direction separate from weight loss.Persistent marketingContinued gray-market promotion despite the failed obesity record.

The market for this

What follows describes how this is bought and sold. It is not a buying guide and it is not an endorsement of any seller.

Available through compounding pharmacies with a prescription, as gray-market research material, or as a supplement, none of which is an approved weight-loss drug. For meaningful weight loss, the evidence-based options are the GLP-1 and GIP medications; anyone using AOD-9604 should understand its own trials did not succeed and insist on tested product if they proceed.

Inexpensive through gray-market, compounded and supplement channels. The low price reflects an unapproved compound with failed efficacy rather than a validated therapy, and gray-market product carries no assurance of identity, dose or purity.

Material comes from compounding pharmacies, Chinese research synthesis and supplement suppliers, with widely varying oversight. For the gray-market route, a certificate of analysis is the only quality check.

Compounding pharmaciesLicensed pharmacies have prepared AOD-9604 for clinician-prescribed use, a more controlled route.China and research vendorsSupply gray-market AOD-9604 as research-use-only material worldwide.Supplement channelIt has been sold as a supplement ingredient under a food-safety claim, separate from injectable use.Original developerMetabolic Pharmaceuticals, which developed and then shelved it as an obesity drug, sought other licensing.

At a glance

Region
HGH 176-191
Effect
Lipolysis without GH growth effects
Origin
Monash University
Phase 3
Failed for obesity

What this entry does not yet cover

What follows is unfinished work on our side, not a finding about AOD-9604.

Nothing outstanding on this one.

Sources

The studies that matter

  • Metabolic Pharmaceuticals animal studies1990s-2000s

    In obese rodents, AOD-9604 reduced weight gain substantially and increased fat breakdown in visceral fat without affecting lean tissue or blood sugar, the promising preclinical basis.

  • 12-week randomized trial2000s

    Patients on AOD-9604 lost an average of about 2.6 kg versus 0.8 kg on placebo, a modest net effect.

  • Six trials, 900+ participants2000s

    A large clinical program tested oral and injectable AOD-9604 for weight loss, producing an unusually large safety dataset.

  • Largest Phase IIb trial (failure)2007

    The pivotal trial failed to reach statistical significance, and development as an obesity drug was terminated that year.

  • Joint and cartilage research2010s

    Later interest explored AOD-9604 for cartilage and osteoarthritis, a separate and less-developed use.