AOD-9604: Fat Loss Peptide Research Profile

AOD-9604 represents one of the more intriguing disappointments in obesity drug development. This synthetic peptide, derived from the fat-burning region of human growth hormone, showed initial promise in animal studies and early human trials during the early 2000s. It was designed to deliver growth hormone's lipolytic effects without triggering unwanted metabolic changes like elevated blood sugar or excessive muscle growth.

Despite $50 million invested by Australian biotech company Metabolic Pharmaceuticals and six clinical trials involving over 900 participants, AOD-9604 failed to demonstrate consistent weight loss in large-scale human studies. Development was terminated in 2007. The peptide never received FDA approval and remains available only as a research compound.

Yet AOD-9604 continues to circulate in wellness clinics and online peptide markets, often promoted with claims disconnected from the clinical evidence. This profile examines what the research actually shows about this peptide's mechanisms, efficacy, safety, and regulatory status.

Quick Facts
What Is AOD-9604?
How AOD-9604 Works: Mechanisms of Action
Research Evidence
Safety Profile and Side Effects
Legal and Regulatory Status
Comparison to Modern Weight Loss Peptides
Frequently Asked Questions
The Bottom Line

Quick Facts

Property	Details
Chemical Name	AOD9604 (Anti-Obesity Drug-9604)
Structure	16-amino acid peptide fragment
Source	Synthetic analog of hGH amino acids 176-191
Mechanism	Beta-3 adrenergic receptor activation, lipolysis stimulation
Primary Use (Research)	Fat metabolism, weight loss
Administration	Subcutaneous injection, oral (tested)
Half-Life	Not well characterized in humans
Developer	Metabolic Pharmaceuticals (Australia)
Development Status	Terminated 2007
FDA Approval	Not approved
WADA Status	Prohibited substance

What Is AOD-9604?

AOD-9604 is a synthetic 16-amino acid peptide derived from the C-terminal region of human growth hormone (hGH), specifically amino acids 176-191. The designation "AOD" stands for "Anti-Obesity Drug," reflecting its original development purpose.

Development History

AOD-9604 was developed in the late 1990s by Professor Frank Ng at Monash University in Melbourne, Australia, and subsequently patented by Metabolic Pharmaceuticals. The goal was to isolate the lipolytic (fat-burning) properties of growth hormone without triggering the hormone's other effects—muscle growth, altered insulin sensitivity, and elevated IGF-1 levels.

Early structure-function studies of human growth hormone had identified the C-terminal region (amino acids 176-191) as the primary site of lipolytic activity. By synthesizing this fragment and adding specific amino acid modifications, researchers created AOD-9604.

Initial animal studies showed promise. In obese Zucker rats, daily oral administration of AOD-9604 at 500 mcg/kg body weight for 19 days reduced body weight gain by over 50% (15.8 g vs. 35.6 g in controls) without adverse effects on insulin sensitivity—a notable advantage over full-length growth hormone.

These encouraging results led Metabolic Pharmaceuticals to invest heavily in human trials. Between 2001 and 2007, the company conducted six randomized, double-blind, placebo-controlled trials across the UK and Australia, involving approximately 925 adult subjects. Total development costs exceeded $50 million.

Relationship to Fragment 176-191

AOD-9604 is often confused with Fragment 176-191, another hGH-derived peptide. While both originate from the same C-terminal region of growth hormone, AOD-9604 includes specific chemical modifications intended to improve stability and oral bioavailability. Importantly, Fragment 176-191 has never been studied in humans, whereas AOD-9604 has undergone extensive clinical testing—albeit with ultimately disappointing results.

Why It Failed

In March 2007, Metabolic Pharmaceuticals announced results from the OPTIONS Study, a 24-week Phase IIb trial involving 536 obese adults. AOD-9604 failed to produce statistically significant weight loss compared to placebo. Following this outcome, development was terminated.

Calzada, Metabolic's parent company, reported to shareholders that AOD-9604 "showed no promise" as a weight loss drug. The peptide's clinical development ended, though the company later licensed manufacturing rights to third parties after learning bodybuilders were importing counterfeit versions from China.

How AOD-9604 Works: Mechanisms of Action

AOD-9604's proposed mechanisms center on fat metabolism, specifically the breakdown of stored triglycerides and inhibition of new fat formation. The peptide's effects appear to involve beta-3 adrenergic receptor signaling, though the exact pathways remain incompletely understood.

Lipolysis Stimulation

Lipolysis is the process by which triglycerides stored in adipose tissue are broken down into free fatty acids and glycerol, which can then be used for energy. AOD-9604 is thought to stimulate this process through activation of beta-3 adrenergic receptors (β3-AR) in fat cells.

In a key study published in Endocrinology (2001), researchers examined the effects of both full-length human growth hormone and AOD-9604 on lipid metabolism in obese mice. Chronic treatment with either compound increased weight loss and enhanced lipolytic sensitivity. Importantly, both hGH and AOD-9604 increased expression of beta-3 adrenergic receptor RNA in obese mice to levels comparable with lean controls.

To test whether beta-3 receptors were required for AOD-9604's effects, researchers treated beta-3 receptor knockout mice with the peptide. In these animals, AOD-9604 produced no changes in body weight or lipolysis, confirming the critical role of this receptor pathway.

Lipogenesis Inhibition

In addition to promoting fat breakdown, AOD-9604 may inhibit lipogenesis—the synthesis of new fat from non-lipid precursors. Research suggests the peptide acts on acetyl-CoA carboxylase, a rate-limiting enzyme in fatty acid synthesis, reducing its activity in liver and fat cells.

This dual action—increasing fat breakdown while reducing fat formation—theoretically creates a favorable metabolic environment for weight loss.

Lack of IGF-1 and Insulin Effects

A defining feature of AOD-9604 is what it doesn't do. Unlike full-length growth hormone, AOD-9604 does not significantly increase insulin-like growth factor 1 (IGF-1) levels and appears to have minimal effects on carbohydrate metabolism. In clinical trials involving 925 participants, AOD-9604 had no effect on serum IGF-1 levels and showed no negative impact on glucose regulation.

This selectivity was the peptide's key selling point—targeted fat loss without the metabolic risks associated with growth hormone therapy.

Mechanism Limitations

Despite extensive preclinical characterization, the mechanism of action of AOD-9604 remains incompletely understood. The peptide clearly shares some biological effects of human growth hormone on adipose tissue but not others, such as IGF-1 production. Critically, the disconnect between promising mechanistic data and failed clinical trials suggests the in vitro and animal model findings did not translate to meaningful fat loss in humans under real-world conditions.

Research Evidence

AOD-9604 has been studied primarily in animal models and human clinical trials focused on obesity treatment. More limited research has examined its potential effects on cartilage regeneration.

Animal Studies

Early rodent studies provided the mechanistic foundation for AOD-9604's development and showed consistent effects on body weight and fat metabolism.

Obese Zucker Rat Study (2000) Published in Hormone and Metabolic Research, this study examined metabolic effects of AOD-9604 in obese Zucker rats. Daily oral dosing at 500 mcg/kg for 19 days reduced body weight gain by more than 50% compared to controls. Unlike chronic treatment with intact growth hormone, AOD-9604 showed no adverse effect on insulin sensitivity—a significant advantage.

Obese Mouse Study (2001) A landmark study published in Endocrinology examined the effects of hGH and AOD-9604 on lipid metabolism in diet-induced obese mice and beta-3 adrenergic receptor knockout mice. Both compounds induced weight loss and increased lipolytic sensitivity following chronic treatment. The study revealed that AOD-9604's effects depend on functional beta-3 adrenergic receptors; when these receptors were genetically removed, the peptide produced no changes in weight or lipolysis.

Human Clinical Trials

Metabolic Pharmaceuticals conducted six randomized, double-blind, placebo-controlled trials between 2001 and 2007, testing various doses and formulations of AOD-9604 in approximately 925 adult subjects.

Early 12-Week Trial (Positive Results) An initial Phase 2 trial tested AOD-9604 in 300 obese patients over 12 weeks across six dose groups: placebo, 1 mg, 5 mg, 10 mg, 20 mg, and 30 mg daily (oral administration). The 1 mg dose group showed the most weight loss, averaging 2.6 kg over 12 weeks compared to 0.8 kg in the placebo group—more than triple the placebo effect.

This result generated significant optimism and media attention. In December 2004, news outlets reported the drug was "highly successful in trials" and would proceed to final-phase testing.

OPTIONS Study (Phase IIb, Failed) The pivotal OPTIONS (Obesity Peptide Trial in Over-weight IndividualS) Study enrolled 536 obese adults in a 24-week randomized, double-blind, placebo-controlled trial. The study tested lower doses of AOD-9604 than previously evaluated, with the primary endpoint of weight loss at 12 weeks.

Results, announced in March 2007, were negative. AOD-9604 failed to induce statistically significant weight loss compared to placebo. Following this outcome, Metabolic Pharmaceuticals terminated development of AOD-9604 as an obesity treatment.

Overall Safety Profile Across all six trials involving 925 patients, AOD-9604 was found to be safe and well tolerated. No serious adverse events were attributed to the peptide, and no anti-AOD-9604 antibodies were detected in any participants. The safety profile was described as "indistinguishable from placebo."

Dosing Regimens Tested

Clinical trials evaluated various protocols, including single doses ranging from 25 to 400 mcg/kg body weight for subcutaneous and intravenous administration, and daily oral doses of 1, 5, 10, 20, and 30 mg evaluated over 12 weeks. Despite testing multiple formulations and dose levels, no regimen produced consistent, clinically meaningful weight loss.

Cartilage Regeneration Research

A separate line of research has explored AOD-9604's potential effects on cartilage and joint health, independent of its weight loss applications.

Rabbit Osteoarthritis Study (2015) Published in Annals of Clinical & Laboratory Science, this study examined intra-articular injection of AOD-9604, with or without hyaluronic acid (HA), in a rabbit model of collagenase-induced osteoarthritis. Four groups were tested: saline control, HA alone, AOD-9604 alone, and AOD-9604 + HA combination.

The combination therapy (AOD-9604 + HA) produced significantly better outcomes than either treatment alone, based on gross morphological and histopathological scoring of cartilage degeneration. The study suggested AOD-9604 may promote proteoglycan and collagen production in chondrocytes and support differentiation of adipose-derived mesenchymal stem cells.

This research remains preliminary, limited to animal models. No human trials have evaluated AOD-9604 for cartilage regeneration or osteoarthritis treatment.

Evidence Summary

The research trajectory of AOD-9604 illustrates a common pattern in drug development: promising preclinical data that fails to translate to human efficacy. Animal studies consistently showed weight loss and metabolic improvements. Small early-phase human trials suggested modest benefit. But when tested in a larger, adequately powered trial—the gold standard for demonstrating efficacy—the peptide did not perform better than placebo.

Safety Profile and Side Effects

AOD-9604's safety profile is one of its few clear strengths. Across clinical trials involving over 900 participants, the peptide demonstrated excellent tolerability with a side effect profile essentially indistinguishable from placebo.

Clinical Trial Safety Data

In the six randomized controlled trials conducted by Metabolic Pharmaceuticals, AOD-9604 was administered daily for periods ranging from 12 to 24 weeks. No serious adverse events were attributed to the peptide. The extensive clinical safety database establishes AOD-9604 as well-tolerated at doses up to 30 mg per day (oral) and up to 400 mcg/kg via injection.

Key safety findings include:

No effect on IGF-1 levels: Unlike full-length growth hormone, AOD-9604 did not alter serum IGF-1 concentrations
No impact on glucose metabolism: No adverse effects on insulin sensitivity or blood glucose regulation
No immunogenicity: No anti-AOD-9604 antibodies were detected in any trial participants
Comparable to placebo: Overall adverse event rates were similar between AOD-9604 and placebo groups

Reported Side Effects

When side effects occur, they are typically mild and transient. The most commonly reported include:

Injection site reactions: Temporary redness, soreness, or swelling at the injection site
Mild gastrointestinal symptoms: Upset stomach or nausea (more common with oral dosing)
Headache: Generally mild and self-limiting
Tingling sensation: Occasional paresthesia

These effects are generally well-tolerated and do not require discontinuation of treatment.

Theoretical Concerns

While clinical trial data shows good short-term safety (up to 24 weeks), several theoretical concerns warrant consideration:

Blood Sugar Effects: Though clinical trials showed no significant impact on glucose metabolism, AOD-9604 might influence blood sugar levels in susceptible individuals, particularly those with diabetes or prediabetes. Close monitoring would be prudent for these populations.

Long-term Safety Unknown: All clinical trials were relatively short (12-24 weeks). The effects of chronic, multi-year use remain unknown.

Pregnancy and Lactation: No safety data exists for use during pregnancy or breastfeeding. AOD-9604 should be avoided in these populations.

Safety Compared to Other Interventions

AOD-9604's safety profile compares favorably to many approved obesity medications and certainly to full-length growth hormone. It lacks the gastrointestinal side effects of GLP-1 receptor agonists like semaglutide and liraglutide, the cardiovascular concerns of older weight loss drugs, and the metabolic complications of growth hormone therapy.

Of course, this favorable safety profile matters little without demonstrated efficacy—a safe but ineffective drug offers no clinical value.

Legal and Regulatory Status

AOD-9604's regulatory status is unambiguous: it is not approved for human use by any major health authority worldwide. Its legal standing has important implications for consumers, healthcare providers, and athletes.

FDA Status

AOD-9604 is not approved by the U.S. Food and Drug Administration (FDA) for any indication. The FDA has not evaluated the peptide for safety, effectiveness, or manufacturing standards in the context of therapeutic use.

In December 2024, the FDA Pharmacy Compounding Advisory Committee (PCAC) reviewed AOD-9604 for potential inclusion on the 503A Bulks List, which would permit compounding pharmacies to use the substance in patient-specific prescriptions. The FDA determined that AOD-9604 (both free base and acetate forms) should not be included on this list.

The FDA's decision cited several concerns:

Limited long-term safety data
Potential peptide impurities in compounded formulations
Questions about immunogenicity (antibody formation)
Lack of demonstrated clinical efficacy

This December 2024 decision closes a pathway that some compounding pharmacies had used to provide AOD-9604 to patients, similar to FDA actions on other peptides following the 2023-2024 GLP-1 shortage.

International Regulatory Status

AOD-9604 lacks approval from other major regulatory bodies:

European Medicines Agency (EMA): Not approved
Therapeutic Goods Administration (TGA), Australia: Not approved (despite being developed in Australia)
Health Canada: Not approved
Medicines and Healthcare products Regulatory Agency (MHRA), UK: Not approved

Research Chemical Status

Without regulatory approval, AOD-9604 is marketed and sold as a "research chemical" or "research peptide" intended "for laboratory research use only" and "not for human consumption." This labeling is largely a legal fiction—many individuals purchase these products for self-administration.

The research peptide market operates in a regulatory gray zone. Products are not manufactured under pharmaceutical GMP (Good Manufacturing Practice) standards, are not tested for purity or potency by regulatory agencies, and may contain contaminants, incorrect concentrations, or even different compounds than labeled.

GRAS Claims

Some vendors have claimed AOD-9604 holds "GRAS" (Generally Recognized as Safe) status, which would allow its use as a dietary supplement ingredient. These claims are misleading. GRAS status does not equal FDA approval for therapeutic use, and recent FDA actions confirm the agency does not recognize AOD-9604 as appropriate for compounding or supplementation.

WADA Prohibited Status

The World Anti-Doping Agency (WADA) classifies AOD-9604 as a prohibited substance under the category of "Growth Hormone Secretagogues and Growth Hormone Releasing Factors." Use of AOD-9604 is banned for athletes in competition.

This prohibition gained public attention in 2013 when the Essendon Football Club in Australia was investigated for administering AOD-9604 to players. While the club argued the peptide was not explicitly listed at the time, WADA and subsequent tribunals held that it fell under prohibited substance categories.

Legal Considerations for Users

Purchasing and possessing AOD-9604 for personal use exists in a legal gray area that varies by jurisdiction. While not a controlled substance like anabolic steroids, using a non-approved research chemical for self-treatment carries risks:

No legal protections if the product causes harm
No assurance of product quality, purity, or sterility
Potential legal liability, particularly for healthcare providers who recommend or supply it
Disqualification risk for competitive athletes

Comparison to Modern Weight Loss Peptides

The landscape of peptide-based obesity treatment has evolved dramatically since AOD-9604's development ended in 2007. Today's FDA-approved peptide therapies for weight loss—primarily GLP-1 receptor agonists—have achieved the clinical efficacy that AOD-9604 failed to demonstrate.

GLP-1 Receptor Agonists

The GLP-1 class represents the current gold standard for peptide-based weight loss, with several members approved by the FDA for chronic weight management.

Semaglutide (Wegovy for obesity, Ozempic for diabetes) produces average weight loss of 15-20% of body weight over 68 weeks when combined with lifestyle modification. In the landmark STEP 1 trial involving 1,961 adults with obesity, participants on semaglutide lost an average of 14.9% of their body weight compared to 2.4% with placebo.

Liraglutide (Saxenda), an earlier GLP-1 agonist, produces more modest weight loss of 5-10% but was the first in the class approved specifically for obesity treatment.

Tirzepatide (Zepbound for obesity, Mounjaro for diabetes), a dual GIP/GLP-1 receptor agonist, has shown even greater efficacy than semaglutide in head-to-head trials, with average weight loss approaching 21% in the SURMOUNT-1 study.

Mechanisms: GLP-1 vs. AOD-9604

These therapies work through fundamentally different mechanisms than AOD-9604:

Feature	AOD-9604	GLP-1 Agonists
Primary Mechanism	Direct lipolysis stimulation via β3-AR	Appetite suppression via hypothalamic GLP-1 receptors
Secondary Effects	Lipogenesis inhibition	Delayed gastric emptying, increased satiety
Hormonal Changes	Minimal (no IGF-1 increase)	Enhanced insulin secretion, suppressed glucagon
Metabolic Effects	Targeted to adipose tissue	Whole-body glucose and appetite regulation

The key difference: GLP-1 agonists produce weight loss primarily by reducing caloric intake through powerful appetite suppression and enhanced satiety. AOD-9604 attempted to increase energy expenditure through direct fat metabolism—a far more challenging intervention.

Clinical Evidence Comparison

Peptide	FDA Approved	Largest Trial N	Average Weight Loss	Statistical Significance
AOD-9604	No	536	No significant difference from placebo	Failed primary endpoint
Liraglutide	Yes (2014)	3,731	5-8%	Strong, consistent
Semaglutide	Yes (2021)	1,961	15-20%	Strong, consistent
Tirzepatide	Yes (2023)	2,539	15-21%	Strong, consistent

The contrast is stark. AOD-9604 failed to demonstrate efficacy in adequately powered trials, while GLP-1 agonists consistently produce clinically meaningful weight loss across multiple large-scale studies.

Side Effect Profiles

AOD-9604's favorable safety profile is one area where it compares well to GLP-1 agonists.

AOD-9604: Minimal side effects, indistinguishable from placebo in trials. No significant gastrointestinal, cardiovascular, or endocrine effects.

GLP-1 Agonists: Commonly cause nausea, vomiting, diarrhea, and constipation, especially during dose titration. These effects lead to treatment discontinuation in 5-10% of users. Rare but serious risks include pancreatitis, gallbladder disease, and potential thyroid effects (though not confirmed in humans).

The trade-off is clear: GLP-1 agonists produce significant weight loss but with notable side effects, while AOD-9604 is well-tolerated but ineffective.

Several other peptides related to growth hormone signaling are sometimes discussed in weight loss contexts:

Fragment 176-191: The unmodified hGH fragment from which AOD-9604 was derived. Importantly, Fragment 176-191 has never been studied in humans. Claims about its efficacy are based on extrapolation from AOD-9604 data—data that ultimately failed to show benefit.

CJC-1295 and Ipamorelin: Growth hormone secretagogues that stimulate pituitary GH release. These have not been studied in large-scale weight loss trials and lack FDA approval.

Tesamorelin: The only FDA-approved GHRH analog, approved specifically for reducing excess abdominal fat in HIV-associated lipodystrophy. It is not approved for general obesity treatment.

The Bottom Line on Comparisons

AOD-9604 belongs to an earlier generation of obesity drug development that focused on directly manipulating fat metabolism. This approach proved less effective than targeting appetite and satiety through GLP-1 signaling.

For individuals seeking peptide-based weight loss treatment, the evidence strongly favors FDA-approved GLP-1 receptor agonists like semaglutide or tirzepatide. These medications have robust clinical evidence, regulatory approval, quality manufacturing standards, and established safety monitoring.

AOD-9604, by contrast, offers theoretical mechanisms without demonstrated efficacy, lacks regulatory oversight, and is available only through unregulated channels of questionable quality.

Frequently Asked Questions

Is AOD-9604 effective for weight loss?

Based on available evidence: no. While early small trials suggested modest weight loss (average 2.6 kg over 12 weeks), the largest and most rigorous trial—the Phase IIb OPTIONS Study with 536 participants—failed to demonstrate statistically significant weight loss compared to placebo. Development was terminated in 2007 due to lack of efficacy. The peptide has never been proven effective in large-scale human studies.

How does AOD-9604 compare to semaglutide (Ozempic/Wegovy)?

The two peptides are not comparable in terms of clinical evidence or regulatory status. Semaglutide is FDA-approved for weight loss and produces average weight loss of 15-20% of body weight in large clinical trials. AOD-9604 failed to demonstrate meaningful weight loss in its pivotal trial and has no regulatory approval. Semaglutide has strong clinical evidence; AOD-9604 does not.

Is AOD-9604 safe?

Short-term safety data (up to 24 weeks) from clinical trials involving over 900 participants shows AOD-9604 is well-tolerated with minimal side effects, comparable to placebo. It does not affect IGF-1 levels, insulin sensitivity, or glucose metabolism—advantages over full-length growth hormone. However, long-term safety beyond 24 weeks is unknown. More importantly, safety without efficacy provides little value.

Can I legally purchase AOD-9604?

AOD-9604 is not approved by the FDA or any major regulatory authority for human use. It is sold as a "research chemical" through online vendors, typically with disclaimers stating "not for human consumption." In December 2024, the FDA determined AOD-9604 should not be available through compounding pharmacies. Purchasing research peptides carries significant risks: no quality assurance, unknown purity, potential contamination, and no legal recourse if harm occurs.

Will AOD-9604 show up on drug tests?

Standard employment drug screenings do not test for peptides like AOD-9604. However, AOD-9604 is prohibited by the World Anti-Doping Agency (WADA). Athletes subject to WADA-compliant testing (Olympic, professional, collegiate sports) can be sanctioned for using AOD-9604. Specialized testing can detect peptides, though such tests are not routine outside of competitive sports.

What is the correct dosage of AOD-9604?

Clinical trials tested various regimens, including oral doses of 1-30 mg daily and subcutaneous injection doses ranging from 25-400 mcg/kg. The most common protocol cited in wellness settings is 250-500 mcg via subcutaneous injection, administered in a fasted state (typically morning before eating). However, no dosage has been established as effective based on clinical evidence. Without FDA approval, there is no "correct" therapeutic dose—only protocols used in failed trials and unregulated wellness applications.

Does AOD-9604 help with muscle growth or recovery?

There is no evidence that AOD-9604 increases muscle mass or improves recovery. The peptide was specifically designed to isolate growth hormone's lipolytic effects while avoiding anabolic (muscle-building) activity. Unlike full-length growth hormone, AOD-9604 does not increase IGF-1, the primary mediator of GH's anabolic effects. Some speculate about cartilage regeneration benefits based on a single rabbit study, but no human data supports use for joint health, recovery, or muscle growth.

Can I combine AOD-9604 with other peptides?

Some wellness clinics and online communities discuss combining AOD-9604 with growth hormone secretagogues like CJC-1295, Ipamorelin, or GLP-1 agonists. There is no clinical research on combination protocols. Such approaches are entirely experimental, carry unknown risks, and lack any evidence of added benefit over monotherapy with FDA-approved options.

Why did AOD-9604 fail in clinical trials if it works in animal studies?

This is one of the most common patterns in drug development. Animal models often fail to predict human outcomes, particularly for complex conditions like obesity influenced by behavior, psychology, environment, and metabolism. AOD-9604's proposed mechanism—direct lipolysis via beta-3 receptor activation—may be less effective in humans than in rodents. Alternatively, compensatory metabolic responses may have blunted any fat-loss effects. The disconnect between promising preclinical data and failed human trials is why large, randomized controlled trials are essential.

The Bottom Line

AOD-9604 is a cautionary tale in peptide drug development. What began as a scientifically rational approach to obesity treatment—isolating growth hormone's fat-burning properties without its metabolic side effects—ended in clinical failure despite $50 million invested and six human trials conducted.

The evidence is clear: AOD-9604 did not produce meaningful weight loss in the large, well-designed trial required for FDA approval. Its development was terminated in 2007. It remains unapproved by any major regulatory authority. In December 2024, the FDA explicitly determined it should not be available through compounding pharmacies.

Yet the peptide persists in wellness clinics and online markets, often promoted with selective citation of early positive findings while ignoring the pivotal failed trial. This is the pattern of questionable peptide marketing—emphasizing mechanisms and animal studies while glossing over lack of human efficacy.

For individuals interested in evidence-based weight loss treatment, the modern alternatives are clear. FDA-approved GLP-1 receptor agonists like semaglutide, liraglutide, and tirzepatide have demonstrated substantial, consistent weight loss in large-scale trials, with regulatory oversight ensuring manufacturing quality and safety monitoring.

AOD-9604 offers none of these assurances. Its primary documented feature is not efficacy but safety—it is well-tolerated because it doesn't do much of anything. A safe but ineffective intervention is not a therapeutic option; it is an expensive placebo purchased through unregulated channels.

The research story of AOD-9604 is not without value. It illustrates the challenges of translating mechanistic biology into clinical benefit, highlights the essential role of large randomized controlled trials, and demonstrates why regulatory approval processes exist. Not every promising molecule succeeds, and failure can teach as much as success.

But as a weight loss treatment in 2026? The evidence is unambiguous. AOD-9604 failed where it mattered most—in proving it works in humans.

This article is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare provider before starting any new treatment. The use of peptides without regulatory approval carries significant risks and is not recommended.

References

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Heffernan M, et al. Metabolic studies of a synthetic lipolytic domain (AOD9604) of human growth hormone. Horm Metab Res. 2000;32(11-12):421-426. https://pubmed.ncbi.nlm.nih.gov/11146367/
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Wilding JPH, et al. Once-Weekly Semaglutide in Adults with Overweight or Obesity. N Engl J Med. 2021;384:989-1002.
Pi-Sunyer X, et al. A Randomized, Controlled Trial of 3.0 mg of Liraglutide in Weight Management. N Engl J Med. 2015;373:11-22.
Jastreboff AM, et al. Tirzepatide Once Weekly for the Treatment of Obesity. N Engl J Med. 2022;387:205-216.
World Anti-Doping Agency. WADA Prohibited List 2024. https://www.wada-ama.org/
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