AOD-9604
Also known as HGH fragment 176-191 modified, Advanced Obesity Drug, AOD9604, Tyr-hGH 177-191
AOD-9604 is a modified 16 amino acid fragment of the C-terminal end of human growth hormone, built to keep the fat burning signal of HGH without the growth or insulin effects. It lost its only real test: large phase 2 trials in obese adults found no meaningful weight loss, and the program was abandoned.
Reviewed by the amino101 editorial team. .
Quick start
What people commonly do. Not a prescription.- Typical dose
- 250 to 500 mcg
- How often
- once daily
- Where
- Subcutaneous, belly or thigh
- Timing
- morning on an empty stomach, or before fasted cardio
- Effects timeline
- no acute effect to notice; any change in body composition is judged at 8 to 12 weeks, and the trials found none
- Storage
- fridge 2 to 8 C once mixed, use within 4 weeks; powder in the fridge or freezer away from light
- Cycle length
- 8 to 12 weeks
- Break between
- 4 weeks, or stop if nothing has changed
A 2 mg vial in 1 mL gives 2 mg per mL, so 250 mcg is about 12 units and 500 mcg is 25 units on an insulin syringe.
Overview
AOD-9604 is a synthetic copy of amino acids 176 to 191 of human growth hormone with an extra tyrosine added at the front for stability. The idea came from Monash University work in the 1990s showing that this tail region of HGH drives fat breakdown in animals without the effects on growth, blood sugar or IGF-1 that make full growth hormone a problem. Metabolic Pharmaceuticals of Melbourne licensed it as an obesity drug, hence the name Advanced Obesity Drug, and took it into human trials in the early 2000s.
The human results are negative and that should be said up front. An early 12 week study hinted at a small weight difference, but the larger 24 week phase 2b program in more than 500 obese adults found no meaningful weight loss compared with placebo, and Metabolic stopped development in 2007. What the trials did show is that AOD-9604 is well tolerated and does not raise IGF-1 or disturb glucose, which the company later used to obtain self-affirmed GRAS status so it could be sold as a food ingredient in the US. GRAS is a food safety designation, not evidence that it works.
It survives in the research market because the rodent lipolysis data are real and because it is cheap to make. Community protocols run 250 to 500 mcg daily by subcutaneous injection, often alongside a growth hormone secretagogue or a GLP-1 drug. In 2023 the FDA put AOD-9604 in Category 2 of the bulk substances list, closing it to compounding pharmacies. This page is educational; it reports what the research and community use look like, not what anyone should do.
How it works
In rodents, the C-terminal region of growth hormone stimulates lipolysis and inhibits lipogenesis in adipose tissue. AOD-9604 appears to do this by raising beta-3 adrenergic receptor expression in fat cells and nudging the balance of fat metabolism toward breakdown, without binding the growth hormone receptor itself. Because it does not act through the GH receptor it does not raise IGF-1, does not promote cell growth and does not cause insulin resistance, which was confirmed in human studies. The problem is that whatever lipolytic signal exists in rodents did not translate into measurable fat loss in people at the doses tested. A separate line of work explored it as a cartilage protective agent in osteoarthritis models, which is unrelated to the fat mechanism.
Where the research stands
Fat lossWeak or mixed
- Obesity and body fat reduction. Rodent studies show lipolysis and weight reduction, but the 24 week phase 2b program in obese adults found no meaningful weight loss versus placebo. Human evidence is negative.
- Fat oxidation. Increased fat oxidation was measured in mice; a small human study reported a transient rise in fat oxidation after single doses that did not translate into weight change.
Joint and cartilageEmerging
- Osteoarthritis. Rabbit knee studies with intra-articular injection plus hyaluronic acid showed less cartilage damage; this has not been tested in people.
Metabolic safetyModerate evidence
- No effect on IGF-1 or glucose. Human trial data consistently show it does not raise IGF-1 or impair glucose handling, which is a safety finding rather than a benefit.
- rodentIn obese mice, chronic AOD-9604 treatment reduced body weight and fat mass while increasing fat oxidation, with no change in food intake or blood glucose.
- human RCTPhase 2b trials in more than 500 obese adults over 24 weeks found no statistically meaningful weight loss versus placebo, and the obesity program was halted in 2007.
- human RCTPooled safety data from the clinical program, covering roughly 900 people, found no effect on IGF-1, glucose tolerance or insulin and a side effect profile similar to placebo.
- rodentIntra-articular AOD-9604 combined with hyaluronic acid reduced cartilage damage in a rabbit model of knee osteoarthritis.
- in vitroIn fat cell cultures, the C-terminal fragment increased expression of the beta-3 adrenergic receptor, a proposed route for its lipolytic effect.
Rodent and in vitro mean no human data for that finding. Human pilot means small, often uncontrolled. Human RCT means randomized and controlled. Clinical means an approved drug with regulatory data.
Levels over time
Modeled from the half-life. Illustrative, not measured.A half-life of 30 min against dosing every 24 h means each dose has cleared before the next. Nothing stacks; you start from zero every time, and the tissue effect is what carries over.
The company reported that it was orally active, which is unusual for a peptide, and the clinical trials used tablets. Published pharmacokinetics for the injectable form are thin, so the half-life here is an estimate.
AOD-9604 dosage and protocols
Community use runs 8 to 12 weeks of daily injections with no loading phase, then a break of about a month. Since the human trials found no weight effect at 24 weeks, there is no evidence that longer runs do more. Most people who try it do so once and judge it against a scale and a tape measure.
| Goal | Dose | Frequency | Route |
|---|---|---|---|
| Standard fat loss protocol, community | 300 mcg | once daily, morning | Subcutaneous, abdomen |
| Higher end | 500 mcg | once daily, before fasted cardio | Subcutaneous, abdomen |
| Lower end or stacked | 250 mcg | once daily | Subcutaneous |
| Oral, as used in the trials | 1 mg | once daily | Oral tablet or sublingual |
Morning fasted dosing is the convention because insulin suppresses lipolysis and the community wants the peptide working while insulin is low. Some inject 20 to 30 minutes before cardio. None of this is supported by trial data; the trials dosed orally without timing instructions and found no weight effect either way.
Community protocols report 250 to 500 mcg once daily by subcutaneous injection. The clinical trials used oral tablets at a range of doses, and some vendors sell oral or sublingual forms.
Dose calculator
U-100 insulin syringeUnits are a volume on the syringe, not an amount of peptide. Concentration changes every time you change the water volume. The standalone calculator explains the math.
| Vial | Suggested water | Concentration | Low dose draw |
|---|---|---|---|
| 2 mg | 1 mL | 2 mg/mL | 12.5 units |
| 5 mg | 2 mL | 2.5 mg/mL | 10 units |
How to reconstitute AOD-9604
- 1
Wash your hands and wipe the work surface. Swab both vial stoppers with alcohol and let them dry.
- 2
Pick the water volume with the calculator above and write it on the vial. The concentration means nothing without it.
- 3
Draw the bacteriostatic water into a mixing syringe.
- 4
Insert at an angle and let the water run down the inside wall. Never squirt it straight onto the powder.
- 5
Swirl gently or leave it to dissolve. Do not shake.
- 6
Label with the date and water volume. Store in the fridge at 2 to 8 C and use within about 4 weeks.
- 7
Unmixed vials keep for months in the fridge and longer in the freezer, sealed and out of light.
- Full walkthrough with syringe reading and site rotation: reconstitution guide.
- ✓White, fluffy cake
Lyophilized powder should look like a small white puck or fluffy cake at the bottom of the vial. That is a proper freeze-dry.
- ✓Clear after mixing
Once dissolved the solution should be water-clear with nothing floating in it.
- !Slight clumping
Small clumps that dissolve with gentle swirling are fine. Shipping compacts powder.
- ✕Collapsed or melted
Powder stuck to the sides, glassy, or shrunken means it got hot in transit. Contact the vendor.
- ✕Cloudy or particles
Persistent cloudiness or visible particles after mixing means degraded or contaminated product. Do not use it.
- Week 1 to 2
Nothing to feel. Mild injection site redness at most; no hunger change, no energy change, no sleep change.
- Week 4 to 8
Any body composition change here is far more likely to come from diet and training than from the peptide, which is what the placebo controlled trials showed.
- Week 8 to 12
The end of a typical run. The honest expectation from the human data is no measurable difference, and continuing beyond this point has no support.
Interactions and stacking
MOTS-ccompatible
Both are metabolic peptides without human weight loss evidence; no interaction known.
5-amino-1MQcompatible
A common fat loss stack targeting different pathways; untested as a pair.
Tesamorelincompatible
Tesamorelin carries the real visceral fat evidence; AOD-9604 adds nothing demonstrated.
Semaglutidecompatible
Some people add AOD-9604 to a GLP-1 protocol hoping to spare muscle or speed fat loss; there is no evidence it does either, and no interaction known.
HGHcompatible
It is a fragment of growth hormone that does not bind the GH receptor, so it does not compete with or add to HGH in any measurable way.
Insulin and diabetes medicationscompatible
Human trials found no effect on glucose or insulin, so there is no expected interaction, though glucose should still be monitored on any fat loss protocol.
Both are sold as metabolic peptides and appear together in fat loss protocols. Neither has human weight loss evidence, so the pairing rests on mechanism and community habit.
A common fat loss stack where 5-amino-1MQ targets the NNMT enzyme and AOD-9604 is added for lipolysis. The combination is untested.
Tesamorelin has real human data on visceral fat, so some protocols add AOD-9604 on top of it. There is no evidence that AOD-9604 adds anything to tesamorelin alone.
Safety
- ▲Injection site redness or itching
- ▲Headache, reported occasionally
- ▲Mild nausea after a dose
- ▲Transient lightheadedness
- ▲Water retention has been reported anecdotally but did not appear in trials
- ▲The best human evidence available says it does not cause meaningful weight loss. Anyone buying it for fat loss should know the trials failed.
- ▲GRAS status is a food ingredient safety decision based on the trial safety data. It says nothing about efficacy and does not make injectable vials a legal drug.
- ▲Prohibited in sport by WADA under S0; several Australian footballers were sanctioned over it in 2013.
- ▲In 2023 the FDA placed it in Category 2, so compounding pharmacies in the US cannot prepare it.
- ▲Side effects in trials were mild and similar to placebo, which is reassuring, but those trials used oral tablets, not research grade injectable powder.
- ▲Injectable vials from the research market have no quality oversight; the trial safety record does not transfer to an untested product.
- ■Signs of an allergic reaction such as hives, swelling or trouble breathing
- ■Persistent injection site reactions that spread or do not settle
- ■Unexplained changes in blood glucose on bloodwork, which would be unexpected and worth investigating
- ■You are subject to anti-doping testing in sport
- ■Twelve weeks have passed with no change, since more of it will not help
Community poll
Self-reported by visitors. Not clinical evidence.AOD-9604: frequently asked
What AOD-9604 dosage do people use?
Community protocols most often report 250 to 500 mcg once daily by subcutaneous injection, usually in the morning before food. The clinical trials used oral tablets at several doses rather than injections. No dosage has ever been shown to cause weight loss in people, so there is no evidence based dosage to point to.
Did AOD-9604 work in human trials?
No. An early 12 week study suggested a small effect, but the larger 24 week phase 2b program in obese adults found no meaningful difference from placebo on body weight. Metabolic Pharmaceuticals dropped the obesity indication in 2007. Vendors that quote the early study without the later one are leaving out the result that matters.
Is AOD-9604 the same as HGH fragment 176-191?
Almost. HGH fragment 176-191 is the raw 16 amino acid tail of growth hormone. AOD-9604 is that fragment with an added tyrosine at the N-terminus to make it more stable. In practice vendors use the names interchangeably, and the rodent data cover both.
Does it raise IGF-1 or affect blood sugar like growth hormone?
The human studies say no. It does not bind the growth hormone receptor, and trial participants showed no change in IGF-1, fasting glucose or glucose tolerance. That is the one solid thing the clinical program established and it is the basis for the GRAS safety opinion.
References
- The effects of human GH and its lipolytic fragment (AOD9604) on lipid metabolism following chronic treatment in obese mice and beta3-AR knock-out mice. Endocrinology, 2001
- Safety and tolerability of the hexadecapeptide AOD9604 in humans. Journal of Endocrinology and Metabolism, 2013
- Efficacy of AOD9604 intra-articular injection combined with hyaluronic acid in a rabbit model of osteoarthritis. BMC Musculoskeletal Disorders, 2015
- Metabolic Pharmaceuticals phase 2b obesity trial results and discontinuation announcement. Metabolic Pharmaceuticals, ASX announcement, 2007