AOD-9604: the basics
What is it?
A synthetic peptide based on part of human growth hormone, developed to investigate effects on fat metabolism.
FDA briefing ↗What do people claim it helps with?
Fat loss without the other effects of growth hormone, and sometimes joint repair. These are not established clinical benefits.
What has research actually shown?
It has been investigated in human obesity studies, but the evidence has not established a dependable weight-loss treatment. Animal fat-metabolism findings are not enough.
FDA briefing ↗Has this been demonstrated in people?
Both preclinical research and human development studies exist. FDA’s review found insufficient support for effectiveness in obesity.
FDA briefing ↗What side effects, risks and unknowns should I understand?
Safety information is incomplete, especially for injected use. Immune reactions and product impurities are concerns.
FDA briefing ↗Is it an approved medicine?
No FDA-approved medicine contains this peptide. Availability online or through a clinic does not mean it has been approved.
FDA briefing ↗Approval here means U.S. FDA approval and applies to a particular product, formulation and use. This is a starting overview, not a complete side-effect list. Sources checked 10 October 2026; independent scientific review pending.
How is it used or studied?
Studied using specific research preparations. There is no FDA-approved treatment formulation; an online vial, capsule or spray is not necessarily the product used in a study.
Different routes and formulations can have different effects. A study of one product does not validate every product with the same peptide name.
A common misunderstanding
A growth-hormone fragment is not interchangeable with growth hormone. “Research use” is not an approval.
What should I ask a clinician?
- What diagnosis or goal are we trying to address, and what established options are available?
- Was the expected benefit shown in people like me, using this exact product?
- How could my medicines, health conditions or pregnancy plans affect the risks?
- What monitoring is needed, and what would tell us the treatment is helping or should be stopped?
What do the research words mean?
- Peptide
- A short chain of amino acids, the building blocks of proteins.
- Preclinical
- Research in cells, tissues or animals before dependable treatment evidence in people.
- Controlled trial
- A study comparing a treatment with another treatment or a placebo to help separate its effects from other explanations.
- Biomarker
- A measurement, such as a hormone level. A change does not necessarily mean someone feels better or lives longer.
AOD-9604 Evidence & Clinical Profile
Human Study Limits
AOD-9604 has been investigated in clinical contexts. Patient outcomes must be evaluated against study size, design, and control cohorts.
Laboratory & In Vivo Assays
Cellular and animal disease models examine receptor binding affinities and signaling cascades, which require human confirmation.
What is AOD-9604?
hGH Fragment 177-191 Derivative is A synthetic 16-amino-acid peptide modeled on the C-terminal lipolytic domain of human growth hormone (residues 177–191 with an added N-terminal tyrosine). It reduced fat in rodent obesity models, but its obesity development programme ended in 2007 after a 536-person trial found no significant weight loss over placebo. It is not an approved medicine and is named on the WADA Prohibited List. Aliases include: Advanced Obesity Drug 9604, Lipolytic fragment, Tyr-hGH177-191.
- Sequence (one-letter)
- YLRIVQCRSVEGSCGF
- Molecular formula
- C78H123N23O23S2
- Molecular weight
- 1815.1 g/mol
- CAS Number
- 221231-10-3
- UNII Code
- 7UP768IP4M
- PubChem CID
- 71300630
Identifiers checked against PubChem and FDA's Global Substance Registration System on 13 October 2026. FDA substance record ↗ · PubChem record ↗ See all names and codes in the peptide name index.
Clinical Trials & Human Cohorts
AOD-9604 was tested in people during an Australian obesity programme in the 2000s, but the trials were never published in full. The summaries below come from FDA’s 2024 review of the company’s own reports, which is why the grade is early human evidence rather than preclinical: human research exists, and it argued against benefit.
OPTIONS study: randomized, placebo-controlled, double-blind trial of oral AOD-9604 in adults with obesity (as described in FDA’s 2024 briefing document) [5]
What was reported
Weight loss compared with placebo at 12 weeks (the primary endpoint) and at 24 weeks was too small to reach statistical significance. The sponsor announced in February 2007 that the results did not support further development for obesity and terminated the programme.
What limits the conclusion
The trial was never published in the medical literature; FDA reconstructed its design and result from the sponsor’s stock-exchange filings. Only the oral route was tested.
Short clinical studies of oral and intravenous AOD-9604 in people with obesity, summarized in a 2013 safety review and in FDA’s 2024 briefing document [5]
What was reported
FDA found that in most studies AOD-9604 failed to show a benefit for weight reduction compared with placebo. The abstract of the 300-person study claimed small weight and waist reductions that FDA judged of unclear meaning.
What limits the conclusion
Available only as short summaries, abstracts and company press releases without full methods or results. FDA identified no human data for the injected or topical routes that are sold online.
How the compound may work
Mechanisms describe how AOD-9604 may affect biological processes. Laboratory findings and patient outcomes answer different questions.
Beta-3 Adrenergic Receptor Expression
Chronic treatment reduced body weight and body fat in obese mice and raised beta-3-adrenergic receptor RNA expression; in knockout mice the weight effect was lost, but the authors concluded lipolysis was not mediated directly through the beta-3 receptor. [1]
Insulin Sensitivity in Rats
Oral AOD9604 for 19 days reduced body weight gain and increased adipose lipolytic activity, without the adverse effect on insulin sensitivity (euglycemic clamp) seen with chronic intact hGH. [3]
Areas Being Studied
These research topics reflect active areas of scientific exploration, distinct from unverified commercial marketing claims.
Obesity (Preclinical)
Reduced body weight gain and body fat in obese rodents; in people, the largest trial found no significant weight loss over placebo. [3]
Cartilage Repair & Osteoarthritis
Intra-articular AOD9604 lowered cartilage degeneration scores versus saline; combining it with hyaluronic acid was more effective than either alone. [2]
Compare the study designs.
| Study | Design / sample | Outcome type | Key limitation |
|---|---|---|---|
| OPTIONS obesity trial · 2007 [5] | Randomized, double-blind, placebo-controlled trial n = 536 |
Clinical endpoint evaluation | The trial was never published in the medical literature; FDA reconstructed its design and result from the sponsor’s stock-exchange filings. Only the oral route was tested. |
| Earlier small oral and intravenous studies · 2013 [5] | Small randomized, placebo-controlled studies lasting one to twelve weeks n = 300 |
Clinical endpoint evaluation | Available only as short summaries, abstracts and company press releases without full methods or results. FDA identified no human data for the injected or topical routes that are sold online. |
Regulatory Status & Clinical Safety
Regulatory Classification
Unapproved drug. In December 2024 FDA’s Pharmacy Compounding Advisory Committee reviewed AOD-9604 for the 503A bulk drug substances list; FDA found no human exposure data for the injected or topical routes. Named on the 2026 WADA Prohibited List under S2.2.3 (growth hormone fragments), prohibited at all times.
Safety Realities & Impurities
Safety depends on the molecule, formulation, route and evidence. A laboratory purity measurement alone cannot establish safety for human use.
Clinical Trials Registry Records
Official registry records from ClinicalTrials.gov. Study registration does not imply government endorsement or guaranteed efficacy.
WADA & Anti-Doping Regulations
WADA Section S2: Prohibited Substance
The World Anti-Doping Agency (WADA) classifies AOD-9604 under Section S2 of the Prohibited List. Prohibited at all times (in- and out-of-competition). Last verified: October 2026.
Research Timeline
-
2000
Rodent Metabolic Study
Oral AOD9604 reduced body weight gain in obese Zucker rats without impairing insulin sensitivity. [3]
-
2001
Beta-3-AR Studies
Chronic treatment studied in obese and beta-3-AR knockout mice. [1]
-
2007
Obesity Programme Terminated
After the 536-person OPTIONS trial missed its primary weight-loss endpoint, the developer ended obesity development. [5]
-
2015
Osteoarthritis Model
Intra-articular AOD9604 tested in a rabbit knee osteoarthritis model. [2]
-
2024
FDA Compounding Review
FDA’s advisory committee briefing found a lack of evidence of effectiveness for obesity and no human exposure data for injected or topical use. [5]
-
2026
WADA S2 Listing
Named as a growth hormone fragment under S2.2.3; prohibited at all times. [4]
What Researchers Still Don't Know
Long-term safety profiles
Multi-year observational data in broader heterogeneous cohorts remains uncharacterized.
Optimal dose-response thresholds
Comparative trials optimizing minimal effective exposure versus adverse event rates.
Formulation bioavailability
Differences between oral, subcutaneous, and modified peptide delivery vehicles.
References
Primary sources verified against PubMed / NLM and regulatory databases.
- Preclinical Study
- Preclinical Study
- Preclinical Study
- Anti-Doping
- Regulatory Review