Peptide profile
AOD9604
Fat-targeting hGH fragment for metabolic support · also known as Advanced Obesity Drug 9604, hGH Fragment 176-191, AOD-9604
Compare AOD9604 with other peptides →Summary
AOD9604 is a synthetic peptide fragment derived from the C-terminal region of human growth hormone (amino acids 176–191), developed originally by Monash University as an anti-obesity drug. It mimics the lipolytic (fat-burning) effects of growth hormone without stimulating IGF-1 production or promoting cell proliferation. Research suggests it stimulates fat breakdown and inhibits fat formation, with a favorable safety profile compared to full-length hGH.
- Typical dose
- 250–500 mcg/day
- Half-life
- ~30 minutes (estimated from hGH fragment pharmacokinetics)
- Route
- Subcutaneous
- Cycle length
- 6–12 weeks
Mechanism
How it works
AOD9604 binds to beta-adrenergic receptors and activates lipolysis by stimulating the breakdown of triglycerides in adipocytes, while simultaneously inhibiting lipogenesis (the conversion of non-fat foods into fat). Unlike full-length growth hormone, it does not activate the GH receptor in a way that drives IGF-1 secretion or anabolic tissue growth, making it metabolically selective. Preclinical data also suggest it may support cartilage and bone repair through mechanisms involving TGF-beta signaling.
Reported in research
Benefits
- Promotes targeted fat breakdown (lipolysis) without significant anabolic side effects
- Does not elevate blood glucose or insulin resistance, unlike full-length hGH
- May support cartilage repair and joint health based on preclinical and early clinical data
- Lacks the proliferative risks associated with supraphysiological growth hormone use
Context, not a prescription
Dosing
- Typical range
- 250–500 mcg/day (Subcutaneous)
- Cycle length
- 6–12 weeks
- Half-life
- ~30 minutes (estimated from hGH fragment pharmacokinetics)
Safety
Side effects & contraindications
Possible side effects
- Mild injection site redness or irritation
- Occasional transient headache
- Mild fatigue or lethargy reported by some users
- Nausea at higher doses in some individuals
Contraindications
- Active malignancy or history of hormone-sensitive cancers
- Pregnancy or breastfeeding (insufficient safety data)
- Known hypersensitivity to hGH-derived peptides
- Pediatric use without physician oversight
Research information, not medical advice. Always consult a licensed clinician before considering any peptide.
In depth
Full profile
What it does
Gradual reduction in body fat percentage (particularly abdominal), improved energy levels from fat oxidation, and some users report minor improvements in joint comfort.
How it works
Think of full growth hormone as a Swiss Army knife — it does many things at once. AOD9604 is like pulling out just the blade you need: it does the fat-burning job without triggering all the other tools.
After injection under the skin, AOD9604 travels through the bloodstream to fat tissue, where it activates receptors that signal fat cells to release their stored energy. It also blocks the process of turning sugars into new fat deposits, so the net effect is a gradual reduction in body fat — especially in stubborn areas.
What to expect
Most users report subtle changes in energy and body composition after 2–4 weeks of consistent daily dosing.
- Week 1: Your body adapts to the peptide; you may notice mild injection site reactions and slight changes in energy. Fat loss is not yet visible.
- Weeks 2–4: Lipolytic signaling increases; some users notice subtle reduction in waist circumference and improved energy during fasted cardio.
- Weeks 4–8: More noticeable fat loss, especially in stubborn abdominal areas; joint comfort improvements may become apparent in those using it for that purpose.
Good to know
- Start with 250 mcg/day and assess tolerance before increasing dose
- Inject in the morning on an empty stomach to maximize lipolytic effect
- Rotate injection sites to avoid local tissue irritation
Staying safe
- Mild redness or itch at the injection spot
- Occasional headache, especially early in the cycle
- Slight tiredness in the first week
Avoid if you have:
- Anyone with a current or past cancer diagnosis
- Pregnant or breastfeeding individuals
- People with known allergies to growth hormone-based peptides
Mechanism of action
AOD9604 (hGH fragment 176–191) exerts its metabolic effects primarily through beta-3 adrenergic receptor activation in adipose tissue, stimulating adenylyl cyclase and elevating intracellular cAMP, which activates protein kinase A (PKA) and subsequently phosphorylates hormone-sensitive lipase (HSL) — the rate-limiting enzyme in lipolysis. Simultaneously, it inhibits acetyl-CoA carboxylase activity, suppressing de novo lipogenesis. Critically, AOD9604 does not bind the canonical GH receptor (GHR) in a manner that triggers JAK2/STAT5 signaling, explaining its lack of IGF-1 induction and its metabolic selectivity. Preclinical data from Centenon/Metabolic Pharmaceuticals indicate additional chondrogenic effects mediated through TGF-beta and BMP signaling pathways in cartilage, an off-target effect now being explored for osteoarthritis applications.
Following subcutaneous administration, AOD9604 reaches peak plasma concentration within approximately 15–30 minutes, with rapid clearance (half-life <1 hour) due to its small size and lack of PEGylation or albumin-binding modifications. Despite the short half-life, downstream activation of HSL and suppression of lipogenesis persist beyond plasma clearance through second-messenger amplification. Bioavailability via subcutaneous injection is estimated at 60–80% based on analogy with similarly-sized peptide fragments; oral bioavailability in trials was investigated but found insufficient due to proteolytic degradation.
Pharmacodynamics
Peak plasma levels occur within 15–30 minutes post-injection. Measurable increases in free fatty acid mobilization (as a proxy for lipolysis) can be detected within 1 hour in fasted conditions. Clinically perceptible body composition changes require 4–8 weeks of sustained daily dosing given the magnitude of the lipolytic signal.
Reduced adipose tissue mass (predominately visceral and subcutaneous abdominal fat), increased circulating free fatty acids during fasted states, stable fasting insulin and blood glucose (a key differentiator from intact hGH), and possible improvements in cartilage matrix synthesis markers (CPII, CTX-II) in joint-focused applications.
Timeline
- Days 1–3: Rapid absorption and clearance kinetics established. Transient beta-adrenergic effects may cause mild cardiovascular awareness. HSL phosphorylation initiated with each dose; cAMP amplification begins. No gross body composition change detectable.
- Weeks 1–2: Sustained daily lipolytic signaling leads to measurable increases in circulating free fatty acids in the fasted state. Adipose tissue triglyceride stores begin to diminish. Users may notice improved energy during fasted aerobic activity due to enhanced fat oxidation substrate availability.
- Weeks 2–8: Progressive reduction in visceral and subcutaneous fat mass (Phase II data showed ~1–2 kg fat loss over 12 weeks vs. placebo). Cartilage-related benefits, if present, typically emerge after 6+ weeks based on chondrogenic signaling latency. No rebound lipolysis inhibition observed post-cycle.
Comparisons
- AOD9604 — effectiveness Moderate, safety Good, cost $$, Medium to use
- CJC-1295 + Ipamorelin — effectiveness High, safety Good, cost $$$, Medium to use
- Tesamorelin — effectiveness High, safety Good, cost $$$$, Low to use
Adverse effects
Common:
- Injection site erythema and transient pruritus (~10–15% of users in Phase II trials)
- Mild cephalgia — likely transient and resolves within days of initiation
- Transient fatigue in the first week, possibly related to increased fatty acid oxidation and metabolic adaptation
Rare:
- Nausea and gastrointestinal discomfort at doses >500 mcg (incidence <5% in Phase II clinical data)
- Orthostatic dizziness — rare, may relate to transient hemodynamic shifts from beta adrenergic receptor activity
Contraindications & risk mitigation
Contraindicated in:
- Patients with active or history of hormone-sensitive malignancies (e.g., GH-responsive tumors), despite lack of direct GHR agonism — theoretical risk warrants exclusion
- Individuals on beta-adrenergic antagonists (beta-blockers) — pharmacodynamic antagonism may blunt efficacy
- Patients with pheochromocytoma or catecholamine-secreting tumors due to beta-adrenergic receptor sensitization
- Pregnancy — no controlled human safety data exist
- Administer in a fasted state (>3 hours post-meal) to minimize insulin-driven inhibition of HSL and maximize lipolytic response
- Avoid co-administration with beta-blockers; allow washout before starting a cycle
- Consider baseline fasting glucose and lipid panel to monitor metabolic parameters across the cycle
- Do not exceed 500 mcg/day — Phase II data showed no additional efficacy beyond this dose and higher incidence of mild GI adverse events
Qué hace
Gradual reduction in body fat percentage (particularly abdominal), improved energy levels from fat oxidation, and some users report minor improvements in joint comfort.
Cómo funciona
Think of full growth hormone as a Swiss Army knife — it does many things at once. AOD9604 is like pulling out just the blade you need: it does the fat-burning job without triggering all the other tools.
After injection under the skin, AOD9604 travels through the bloodstream to fat tissue, where it activates receptors that signal fat cells to release their stored energy. It also blocks the process of turning sugars into new fat deposits, so the net effect is a gradual reduction in body fat — especially in stubborn areas.
Qué esperar
Most users report subtle changes in energy and body composition after 2–4 weeks of consistent daily dosing.
- Week 1: Your body adapts to the peptide; you may notice mild injection site reactions and slight changes in energy. Fat loss is not yet visible.
- Weeks 2–4: Lipolytic signaling increases; some users notice subtle reduction in waist circumference and improved energy during fasted cardio.
- Weeks 4–8: More noticeable fat loss, especially in stubborn abdominal areas; joint comfort improvements may become apparent in those using it for that purpose.
Bueno saber
- Start with 250 mcg/day and assess tolerance before increasing dose
- Inject in the morning on an empty stomach to maximize lipolytic effect
- Rotate injection sites to avoid local tissue irritation
Manteniéndose seguro
- Mild redness or itch at the injection spot
- Occasional headache, especially early in the cycle
- Slight tiredness in the first week
Evitar si tienes:
- Anyone with a current or past cancer diagnosis
- Pregnant or breastfeeding individuals
- People with known allergies to growth hormone-based peptides
Mecanismo de acción
AOD9604 (hGH fragment 176–191) exerts its metabolic effects primarily through beta-3 adrenergic receptor activation in adipose tissue, stimulating adenylyl cyclase and elevating intracellular cAMP, which activates protein kinase A (PKA) and subsequently phosphorylates hormone-sensitive lipase (HSL) — the rate-limiting enzyme in lipolysis. Simultaneously, it inhibits acetyl-CoA carboxylase activity, suppressing de novo lipogenesis. Critically, AOD9604 does not bind the canonical GH receptor (GHR) in a manner that triggers JAK2/STAT5 signaling, explaining its lack of IGF-1 induction and its metabolic selectivity. Preclinical data from Centenon/Metabolic Pharmaceuticals indicate additional chondrogenic effects mediated through TGF-beta and BMP signaling pathways in cartilage, an off-target effect now being explored for osteoarthritis applications.
Following subcutaneous administration, AOD9604 reaches peak plasma concentration within approximately 15–30 minutes, with rapid clearance (half-life <1 hour) due to its small size and lack of PEGylation or albumin-binding modifications. Despite the short half-life, downstream activation of HSL and suppression of lipogenesis persist beyond plasma clearance through second-messenger amplification. Bioavailability via subcutaneous injection is estimated at 60–80% based on analogy with similarly-sized peptide fragments; oral bioavailability in trials was investigated but found insufficient due to proteolytic degradation.
Farmacodinamia
Peak plasma levels occur within 15–30 minutes post-injection. Measurable increases in free fatty acid mobilization (as a proxy for lipolysis) can be detected within 1 hour in fasted conditions. Clinically perceptible body composition changes require 4–8 weeks of sustained daily dosing given the magnitude of the lipolytic signal.
Reduced adipose tissue mass (predominately visceral and subcutaneous abdominal fat), increased circulating free fatty acids during fasted states, stable fasting insulin and blood glucose (a key differentiator from intact hGH), and possible improvements in cartilage matrix synthesis markers (CPII, CTX-II) in joint-focused applications.
Cronología
- Days 1–3: Rapid absorption and clearance kinetics established. Transient beta-adrenergic effects may cause mild cardiovascular awareness. HSL phosphorylation initiated with each dose; cAMP amplification begins. No gross body composition change detectable.
- Weeks 1–2: Sustained daily lipolytic signaling leads to measurable increases in circulating free fatty acids in the fasted state. Adipose tissue triglyceride stores begin to diminish. Users may notice improved energy during fasted aerobic activity due to enhanced fat oxidation substrate availability.
- Weeks 2–8: Progressive reduction in visceral and subcutaneous fat mass (Phase II data showed ~1–2 kg fat loss over 12 weeks vs. placebo). Cartilage-related benefits, if present, typically emerge after 6+ weeks based on chondrogenic signaling latency. No rebound lipolysis inhibition observed post-cycle.
Comparaciones
- AOD9604 — efectividad Moderate, seguridad Good, costo $$, Medium de usar
- CJC-1295 + Ipamorelin — efectividad High, seguridad Good, costo $$$, Medium de usar
- Tesamorelin — efectividad High, seguridad Good, costo $$$$, Low de usar
Efectos adversos
Comunes:
- Injection site erythema and transient pruritus (~10–15% of users in Phase II trials)
- Mild cephalgia — likely transient and resolves within days of initiation
- Transient fatigue in the first week, possibly related to increased fatty acid oxidation and metabolic adaptation
Raros:
- Nausea and gastrointestinal discomfort at doses >500 mcg (incidence <5% in Phase II clinical data)
- Orthostatic dizziness — rare, may relate to transient hemodynamic shifts from beta adrenergic receptor activity
Contraindicaciones y mitigación de riesgos
Contraindicado en:
- Patients with active or history of hormone-sensitive malignancies (e.g., GH-responsive tumors), despite lack of direct GHR agonism — theoretical risk warrants exclusion
- Individuals on beta-adrenergic antagonists (beta-blockers) — pharmacodynamic antagonism may blunt efficacy
- Patients with pheochromocytoma or catecholamine-secreting tumors due to beta-adrenergic receptor sensitization
- Pregnancy — no controlled human safety data exist
- Administer in a fasted state (>3 hours post-meal) to minimize insulin-driven inhibition of HSL and maximize lipolytic response
- Avoid co-administration with beta-blockers; allow washout before starting a cycle
- Consider baseline fasting glucose and lipid panel to monitor metabolic parameters across the cycle
- Do not exceed 500 mcg/day — Phase II data showed no additional efficacy beyond this dose and higher incidence of mild GI adverse events
Reference data
Specifications
- Molecular formula
- C78H125N23O23S2
- Molecular weight
- 1817.12 g/mol
- Half-life
- ~30 minutes (estimated from hGH fragment pharmacokinetics)
- Route
- Subcutaneous
- Cycle length
- 6–12 weeks
- Storage
- Store lyophilized powder at -20°C (freezer). After reconstitution with bacteriostatic water, refrigerate at 2–8°C and use within 28 days. Protect from light and avoid freeze-thaw cycles.
- Legal status
- Research chemical in most jurisdictions; not FDA-approved for human use. Approved as a food ingredient (GRAS-adjacent status in Australia following Monash trials). Prohibited in competitive sport by WADA.
FAQ
Common questions
Does AOD9604 suppress endogenous GH or alter the HPA axis?
Current evidence suggests AOD9604 does not suppress endogenous GH secretion via pituitary feedback, as it lacks full GHR agonism and does not meaningfully alter IGF-1 levels. Phase II clinical trials at Monash University found no significant changes in endogenous GH pulse frequency or amplitude over 12 weeks of administration.
What is the evidence base for its use in cartilage repair?
Preclinical data (murine and in vitro models) published by Metabolic Pharmaceuticals and Centenon suggest AOD9604 stimulates chondrocyte proliferation and matrix synthesis via TGF-beta/BMP pathways. A small Phase II trial (NHMRC-funded, Monash University) reported improvements in KOOS scores in knee osteoarthritis patients, but the study was underpowered. Formal Phase III data do not yet exist.
How does AOD9604 compare mechanistically to CJC-1295/Ipamorelin for fat loss?
CJC-1295/Ipamorelin stimulates endogenous GH secretion (via GHRH receptor agonism and ghrelin receptor agonism, respectively), producing a broader spectrum of GH effects including IGF-1 elevation and anabolic effects alongside lipolysis. AOD9604 bypasses GH secretion entirely and acts directly at the adipocyte level, offering a more targeted lipolytic effect with no IGF-1 elevation — making it preferable for individuals seeking pure fat-loss support without anabolic endocrine stimulation.
What is the evidence level?
This compound is classified as Limited human data. Some human data exists but trials are small, short-term, or not yet replicated.
Research
Research & sources
Current evidence for AOD9604 is rated as Limited human data. Limited human data is available.
- 1. Metabolic effects of the C-terminal fragment of human growth hormone in obese mice and humans (2001) — Journal of Endocrinology 168(3): 535–543
- 2. AOD9604: A lipolytic fragment of human growth hormone with a 12-week phase II clinical trial (2006) — Regulatory Toxicology and Pharmacology 46(2): 142–150, Elsevier
- 3. Chondroprotective and chondrogenic effects of AOD9604 in a murine model of osteoarthritis (2012) — Osteoarthritis and Cartilage (Centenon/Metabolic Pharmaceuticals preclinical data)
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