AOD-9604 is a 16-amino-acid synthetic peptide. It corresponds to the last 15 amino acids of human growth hormone (positions 177–191) with an extra tyrosine added at one end to stabilise the molecule. It is sometimes called HGH Fragment 176–191 or hexadecapeptide 177–191.

Researchers studied AOD-9604 to see whether the fat-metabolism part of growth hormone could work without the muscle-building, blood-sugar, and IGF-1 effects of the full hormone. Most public attention has been on fat loss, but separate animal work has also looked at joint and cartilage research.

Published human research with AOD-9604 used both intravenous and oral routes. Subcutaneous injection is the most common research-context format today, but no published human pharmacokinetic study has formally characterised subcutaneous AOD-9604 (this gap was specifically called out in FDA's December 2024 review).

Common Research-Planning Structure (Subcutaneous)

Research-context daily protocol with a 5 mg vial reconstituted to 3.0 mL (~1.667 mg/mL)

Phase	Daily Dose	Volume	Units (U-100)
Initial 4 weeks	300 mcg	0.18 mL	18 units
Maintenance (Weeks 5–12)	500 mcg	0.30 mL	30 units
Optional extension	300–500 mcg	0.18–0.30 mL	18–30 units

Cycle Guidelines

Approach	Duration	Review Point	Notes
Short trial arm	12 weeks	Week 12	METAOD005 used 12 weeks of oral doses 1–30 mg/day in 300 obese adults.
Phase 2b trial arm	24 weeks	Weeks 12 and 24	METAOD006 (OPTIONS) used 24 weeks at oral doses 0.25, 0.5, or 1 mg/day in 502 obese adults; primary endpoint not met.
Community research planning	8–16 weeks	Every 4 weeks	Common research-planning structure with optional review points; not from a controlled trial.

Plan based on subcutaneous research dosing of 300–500 mcg/day from a 5 mg vial reconstituted with 3.0 mL bacteriostatic water. All supplies available at lalabpeptides.co.za

Injection Supplies

Item	Notes
Alcohol Swabs	Sterile alcohol pads — clean vial stopper and injection site before each use
Insulin Syringes (U-100)	0.3 mL / 30-unit to 1 mL / 100-unit — 0.3 mL most practical for 18–30 unit draws
Bacteriostatic Water	3.0 mL per 5 mg vial for reconstitution. 10 mL bottles are the common research-supply size
Peptide Fridge	Store reconstituted vials at 2–8°C. Lockable fridge recommended

Standard Reconstitution Steps

AOD-9604 was designed to copy the fat-metabolism end of human growth hormone without the rest of growth hormone's effects. In simple terms, growth hormone has a region near one end of its molecule that signals fat cells to release stored fat. AOD-9604 is a synthetic copy of that region, plus one extra amino acid for stability.

In animal research, AOD-9604 has done two main things. First, it stimulates lipolysis — the breakdown of stored fat into free fatty acids the body can use as fuel. Second, it appears to suppress lipogenesis, which is the storage of new fat. In Heffernan et al. 2001, AOD-9604 lost most of this fat-metabolism effect in mice that were genetically missing the beta-3 adrenergic receptor, suggesting that pathway carries part of the signal.

Importantly, AOD-9604 does not appear to bind to the growth hormone receptor itself in cell-binding studies. That is the proposed reason it does not raise IGF-1 levels or impair insulin sensitivity in animal work, in contrast to full-length growth hormone. The molecular target that AOD-9604 actually binds is still unidentified, which the FDA explicitly noted in its December 2024 evaluation.

Cartilage and Joint Research Context

A separate animal line of work has investigated AOD-9604 in joint research. Kwon and Park 2015 reported that intra-articular AOD-9604 injections, especially when combined with hyaluronic acid, improved cartilage scores and reduced lameness in a rabbit collagenase-induced osteoarthritis model. This is a single rabbit study, not human evidence.

What Is Supported in Animal Models

• Increased lipolysis, increased fat oxidation, decreased lipogenesis
• No apparent effect on plasma glucose or insulin sensitivity
• Signal that intact beta-3 adrenergic receptor activity matters for the fat-loss effect

What Is Unknown

The actual molecular receptor that AOD-9604 binds. FDA's 2024 review states the mechanism of action is still unknown, which limits how confidently any specific physiological effect can be predicted in humans.

AOD-9604 is a research compound. Anyone considering it should consult a qualified clinician before use. There is no FDA-approved indication for any patient population.

Groups With Limited or No Safety Data

Published human trials with AOD-9604 enrolled adults with obesity (BMI 30–45 kg/m²), generally aged 18–65. Outside of that group, the following populations have no published exposure data:

• People who are pregnant, trying to become pregnant, or breastfeeding
• Anyone under 18
• People with active or recent cancer history (the trial record contains a small number of cancers in the 12-week oral arm)
• People with significant liver disease (the 9-month monkey study showed dose-dependent periportal hepatocyte vacuolation that FDA flagged as a possible safety signal)
• People with poorly controlled bone-turnover conditions, until the dose-dependent osteocalcin changes seen in the 26-week rat study are better understood

Athletes and Competition

AOD-9604 is on the World Anti-Doping Agency Prohibited List under category S2.2 (peptide hormones, growth factors, related substances, and mimetics). Athletes subject to WADA, USADA, NCAA, or any sport-governing-body testing should not use AOD-9604 in any form. Metabolites can be detected in urine.

Medication Interactions

Specific drug-interaction studies with AOD-9604 have not been published. Any medication that affects glucose, lipid metabolism, growth hormone signalling, or beta-adrenergic activity could in theory interact, but evidence is absent. Discuss any active prescription with a qualified clinician before considering use.

AOD-9604 has one of the largest safety datasets of any research peptide in this category. Six controlled trials in approximately 900 participants are summarised in Stier et al. 2013, and FDA's December 2024 review lists the same trial set. The safety record is generally placebo-like, but several specific findings deserve attention.

Observed Effects in Human Trials

Reported adverse events across the IV and oral trials included headache, fatigue, dizziness, nasopharyngitis, diarrhoea, flatulence, increased appetite, nausea, and back pain. Most were mild or moderate. One report of severe chest tightness in the 50 mg/kg IV arm was deemed possibly related. A small number of cancers (basal cell carcinoma, breast cancer, malignant melanoma, lipoma, squamous cell carcinoma) were reported during the 12-week oral METAOD005 trial; investigators considered them unrelated to study drug. Anti-AOD-9604 antibodies were not detected in tested participants.

Theoretical and Route-Specific Risks

FDA's 2024 review specifically flagged that no published human exposure data exists for the subcutaneous, transdermal, or intranasal routes that compounding pharmacies have offered. Injectable routes carry a particular concern for immunogenicity from peptide aggregation and impurities, and FDA noted the available certificates of analysis for AOD-9604 bulk drug substances did not consistently control for impurities, aggregates, or microbial limits.

Animal Toxicology Signals

Two animal findings reviewed by FDA are worth tracking even if they did not surface clinically: In a 26-week rat oral toxicity study, AOD-9604 produced dose-dependent changes in serum osteocalcin (a bone-turnover marker) at week 13, with the direction reversing by week 26. In a 9-month monkey oral toxicity study, all female monkeys in the high-dose group showed minimal-to-slight periportal hepatocyte vacuolation. FDA flagged both as potentially clinically relevant signals that warrant caution.

Quality-Control Risk

Because there is no FDA-approved AOD-9604 product, all material in circulation comes from research-supply or compounding sources. FDA noted that reviewed CoAs from suppliers did not consistently include controls for impurities, aggregates, or bacterial endotoxins. That makes supplier transparency, third-party HPLC purity confirmation, and lot-specific certificates non-negotiable for any research-context sourcing.

What the Trials Measured and When

The METAOD005 oral trial measured weight at 12 weeks. Reported weekly weight-loss differences over placebo were small (in the range of -0.06 to -0.15 kg/week, depending on dose). The METAOD006 (OPTIONS) oral Phase 2b trial measured weight at 12 and 24 weeks; the difference between AOD-9604 arms and placebo was not statistically significant at either point, and development was terminated.

Markers Reasonable to Monitor

• Weight, waist circumference, and body composition
• Fasting glucose and a basic lipid panel (AOD-9604 did not raise glucose or worsen lipids in trials, but baseline confirmation is useful)
• IGF-1 (trial data suggests no meaningful change; documentation can support that if any existing liver concern is present)
• Liver enzymes if any pre-existing liver concern exists, given the monkey toxicology signal
• Injection-site inspection for redness, induration, or lipohypertrophy

What Cannot Be Promised

Specific weight-loss targets, body-composition changes, or joint outcomes cannot be promised based on current evidence. Phase 2b primary endpoints failed in the largest published trial. Anyone planning research-context use should treat outcome reports cautiously and weigh the FDA-approved alternatives discussed in the comparisons section.

AOD-9604 is usually discussed in a fat-loss and metabolic research context. Lab monitoring is mainly pathway-based because routine clinical monitoring standards are not established for this peptide.

Marker	Why It Matters	Timing
Comprehensive metabolic panel (CMP)	Reviews liver enzymes, kidney markers, electrolytes, and glucose in one broad safety panel	Baseline
A1c	Shows the longer-term blood-sugar pattern that may matter during fat-loss or metabolic protocols	Baseline
Fasting glucose	Gives a simple snapshot of current glucose control before interpreting appetite or weight changes	Follow-up
Lipid panel	Tracks cholesterol and triglyceride changes that may shift during weight-loss phases	Follow-up
TSH and free T4	Helps rule out thyroid-related reasons for unexpected weight, energy, or metabolic changes	Optional

Simple Timing Framework

AOD-9604 is unusual among research peptides because it actually completed real Phase 1 and Phase 2 clinical trials. Six trials totalling roughly 900 participants are summarised in Stier et al. 2013 and re-evaluated in FDA's 2024 PCAC briefing.

Strongest Human Evidence

The METAOD006 (OPTIONS) Phase 2b trial randomised 502 adults with obesity (BMI 30–43 kg/m²) to oral AOD-9604 (0.25, 0.5, or 1 mg/day) or placebo for 24 weeks alongside a supervised diet and exercise program. The trial was powered to detect a 1.8 kg difference vs placebo. The primary endpoint was not met. Metabolic Pharmaceuticals terminated development for obesity in February 2007.

Earlier Oral Trial

METAOD005 randomised 300 adults with obesity to oral AOD-9604 (1, 5, 10, 20, or 30 mg/day) or placebo for 12 weeks. Authors reported small statistically significant differences in weekly weight loss at the 1 mg dose with a non-linear dose response, but the abstract data has not been published in full peer-reviewed form.

IV and Short-Duration Oral Trials

METAOD001–004 enrolled smaller groups of healthy or obese men with single doses or 1-week dosing across IV (25–400 mcg/kg) and oral (9–54 mg) routes. These established short-term safety and pharmacology context but were not designed to demonstrate weight loss efficacy.

Preclinical Fat-Loss Evidence

Ng et al. 2000 in Hormone Research showed that 21-day oral AOD-9604 (500 mcg/kg/day) reduced body weight gain by roughly 50% in obese Zucker rats with no insulin sensitivity penalty. Heffernan et al. 2001 in Endocrinology showed reduced body weight gain with 14-day AOD-9604 in obese (ob/ob) mice and identified the beta-3 adrenergic receptor dependency.

What Is Missing

There is no published human pharmacokinetic study of subcutaneous AOD-9604, no published human topical or intranasal exposure data, no Phase 3 efficacy trial, no long-term safety data beyond 24 weeks, and no published human cartilage or joint outcome data.

State	Storage Condition	Notes
Lyophilised (dry powder)	2–8°C refrigerated, away from light	Some sources suggest short-term room temperature is acceptable; refrigeration is standard
Reconstituted (liquid)	2–8°C refrigerated	Use within 28–30 days. Label with reconstitution date and discard date
Freeze-thaw cycles	Avoid repeated cycling	Repeated freezing and thawing degrades peptide integrity
Transport	Cold pack if over 30 minutes in warm conditions	LA LAB ships with ice packing for integrity in transit