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aod-9604-notes.peptides6155.com › Data › Background And Development History — Worked Examples

Background And Development History — Worked Examples

By Editorial Desk · published 2026-04-17 · last reviewed 2026-05-14 · Data

Everything below concerns hGH fragment. We keep the language plain, cite what the science says, and separate well-supported claims from open questions.

Last reviewed on 2026-05-14. Where a claim depends on a specific study, the study is described rather than over-claimed.

Background and Development History

AOD9604 is a synthetic peptide modeled on the C-terminal region of human growth hormone. It corresponds to a short sequence near the end of the 191-amino-acid hormone, often described as residues 176–191 or a related fragment. Researchers designed it to separate metabolic effects from the growth-promoting actions of full-length growth hormone. Early work in the 1990s explored it as a candidate for weight and lipid disorders. It is not a naturally circulating hormone fragment produced in large amounts.

Laboratory studies have reported that AOD9604 can increase lipolysis and reduce lipid accumulation in fat cells. The precise molecular target remains uncertain, and the compound does not appear to activate the growth hormone receptor in the same way as full-length hGH. Proposed mechanisms include effects on beta-adrenergic signaling and enzymes involved in fatty acid synthesis, but these pathways are not firmly established. Because most evidence comes from cell and animal models, whether the same effects occur in humans is an open question.

Clinical development of AOD9604 included trials in people with obesity, but the results did not lead to approval as a prescription medicine in major markets. Interest later shifted to research settings and to unapproved products marketed for body composition. Regulatory agencies have questioned whether the peptide qualifies as a dietary ingredient, and some have issued warnings about its presence in supplements. Long-term human safety data are limited, and questions about efficacy, dosing, and target populations remain unresolved.

Research and Regulatory Context

Regulatory bodies have taken different approaches to AOD-9604. It is not approved as a prescription medicine by major agencies such as the U.S. Food and Drug Administration or the European Medicines Agency. In sport, the World Anti-Doping Agency prohibits peptide hormones, growth factors, and related substances, and AOD-9604 has been treated as a prohibited substance. These regulatory decisions reflect concerns about safety, efficacy, and potential misuse rather than proof of benefit.

Research on AOD-9604 also examines how the peptide is measured in biological samples. Analytical methods may include liquid chromatography coupled with mass spectrometry, immunoassays, or both. Detection can be challenging because the peptide is small and may be present at low concentrations. Published methods vary in sensitivity and specificity, so comparative interpretation requires attention to validation details. The presence of related hGH fragments can complicate identification in some matrices.

Aod-9604 at a glance

PropertyValueNotes
Molecular classSynthetic peptideDerived from C-terminal region of human growth hormone
Approximate molecular massAbout 1.8 kDaVaries with sequence length and counterions
Confirmed receptor targetNone establishedNo confirmed growth hormone receptor agonism
Reported in vitro activityLipolysis stimulation and lipogenesis inhibitionObserved mainly in adipocyte models; human relevance uncertain
Regulatory statusNot approved as a drug in major marketsMay be treated differently across jurisdictions; not a recognized dietary ingredient in some countries

Identity and Molecular Context

AOD-9604 is a synthetic peptide modeled on the C-terminal region of human growth hormone. It corresponds to residues 176-191 of the 191-amino-acid hGH sequence. The fragment is not the full hormone and lacks the receptor-binding region associated with growth and metabolic effects of hGH. Researchers developed it to isolate a specific portion of hGH for study. Its exact sequence and length are often stated in peptide catalogs and patents.

The peptide is frequently described as a growth hormone fragment, although it is chemically distinct from full-length hGH. AOD-9604 contains 16 amino acids and includes two cysteine residues that can form an intramolecular disulfide bond. In solution, this structural feature can influence folding, aggregation, and stability. Published descriptions sometimes call it hGH 176-191 or AOD9604, with spacing and capitalization varying. Such naming differences can complicate literature searches, database entries, and product verification.

Researchers have studied the fragment in cell and animal models to understand its metabolic actions. Some experiments report effects on fat breakdown and fat storage pathways, but the underlying mechanism remains incompletely defined. AOD-9604 does not appear to stimulate the same broad growth hormone receptor signaling as full-length hGH. Whether its observed activities arise from direct receptor interactions or downstream metabolic changes is an open question. Results from different assays are not always consistent.

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Identity and Research Origin

Development of AOD-9604 began in the 1990s as scientists sought to isolate metabolic effects of growth hormone without its growth-promoting actions. Early laboratory work focused on fat cells and animal models. Several human trials followed, examining changes in body composition and fat mass. Results have been mixed, and the peptide has not progressed to widespread clinical approval. Interest continues in research settings, particularly regarding its mechanism and potential metabolic targets.

Regulatory status varies by country. In the United States, AOD-9604 is not approved as a prescription drug. It is sometimes sold as a research chemical or dietary supplement, though such marketing may fall outside legal frameworks. The World Anti-Doping Agency prohibits its use in sport. Researchers must obtain it through legitimate suppliers and follow institutional rules. Its legal classification continues to evolve as authorities increasingly assess peptide products more broadly.

AOD-9604 is a synthetic peptide whose sequence matches the C-terminal fragment of human growth hormone, specifically residues 176 through 191. This region differs from the full hormone in its receptor interactions. The peptide is not a growth hormone secretagogue and does not bind the growth hormone receptor in the same manner. Researchers have examined it for effects on lipid metabolism, but its exact pharmacological profile remains an active area of study.

Identity and Research Context

Early interest in AOD-9604 centered on whether a fragment of human growth hormone could influence fat metabolism without the broader effects of the full hormone. Cell and animal studies reported changes in fat storage and breakdown. Human trials followed, but the results were not strong enough to secure regulatory approval. The compound remains available for laboratory research, and its clinical potential is still described as uncertain. Studies continue to examine its activity and safety profile.

AOD-9604 is a synthetic peptide that corresponds to a short section of human growth hormone. It is commonly identified as hGH fragment 176-191 because its sequence matches residues at the C-terminal end of the hormone. The molecule contains sixteen amino acids and is made by solid-phase peptide synthesis. Researchers study it for metabolic effects rather than for the growth-promoting actions associated with full human growth hormone. Its small size distinguishes it from the complete 191-amino-acid hormone.

Several names appear in scientific and commercial settings. AOD9604 and AOD-9604 are development codes used interchangeably, while hGH fragment 176-191 describes the same region. The peptide includes a disulfide bond between two cysteine residues, which helps shape its three-dimensional structure. Different suppliers may provide acetate or other salt forms, and purity can vary. These differences matter because analytical tests and biological assays can respond to the specific form being studied.

Background from the literature

=== Administrative work === In 1959, after offering advice to Yale president A. Whitney Griswold on strengthening the sciences at Yale, Fruton became director of the division of science, a position he held until 1962. His work led to the creation of the short-lived department of molecular biology and biophysics (MBB), although his initial proposal to create a similar department that combined the existing biophysics and biochemistry departments was rejected. Fruton became burnt out on Yale politics after an extended conflict with provost Kingman Brewster, in which Brewster attempted to bypass Fruton's science advisory committee and create a molecular biology department independent of biochemistry department; the MBB department was created only after Brewster had failed to attract a prominent scientist from outside Yale to head a molecular biology department, and the department of biochemistry remained separate as part of the medical school until the creation of the department of molecular biophysics & biochemistry (MB&B) in 1969 (which was itself created after a lengthy and unsuccessful attempt to find a suitably eminent replacement for Fruton to head the department of biochemistry). Fruton was elected to the American Philosophical Society in 1968.

== Pharmacology == Nordazepam is a partial agonist at the GABAA receptor, which makes it less potent than other benzodiazepines, particularly in its amnesic and muscle-relaxing effects. Its elimination half-life is between 36 and 200 hours, with wide variation among individuals; factors such as age and sex are known to impact it. The variation of reported half-lives are attributed to differences in nordazepam metabolism and that of its metabolites as nordazepam is hydroxylated to active metabolites such as oxazepam, before finally being glucuronidated and excreted in the urine. This can be attributed to extremely variable hepatic and renal metabolic functions among individuals depending upon a number of factors (including age, ethnicity, disease, and current or previous use/abuse of other drugs/medicines).

=== Pharmacokinetics === Equilin has about 8% of the relative binding affinity of testosterone for SHBG, relative to 12% in the case of estrone. In terms of plasma protein binding, it is bound 26% to SHBG and 13% to albumin. The metabolic clearance rates of equilin and equilin sulfate are 2,640 L/day/m2 and 175 L/day/m2, respectively. In accordance, the biological half-life of equilin sulfate is substantially longer than that of equilin. Equilin is converted into 17β-dihydroequilin in the liver and in other tissues. Equilin and 17β-dihydroequilin can also be transformed into equilenin and 17β-dihydroequilenin. Equilin is excreted in the form of glucuronide conjugates.

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Sources: en.wikipedia.org

Further detail

=== EC 1.7.1 With NAD+ or NADP+ as acceptor === EC 1.7.1.1: nitrate reductase (NADH) EC 1.7.1.2: nitrate reductase (NAD(P)H) EC 1.7.1.3: nitrate reductase (NADPH) EC 1.7.1.4: nitrite reductase (NAD(P)H) EC 1.7.1.5: hyponitrite reductase EC 1.7.1.6: azobenzene reductase EC 1.7.1.7: GMP reductase EC 1.7.1.8: deleted EC 1.7.1.9: nitroquinoline-N-oxide reductase EC 1.7.1.10: hydroxylamine reductase (NADH) EC 1.7.1.11: 4-(dimethylamino)phenylazoxybenzene reductase EC 1.7.1.12: N-hydroxy-2-acetamidofluorene reductase EC 1.7.1.13: preQ1 synthase EC 1.7.1.14: nitric oxide reductase (NAD(P), nitrous oxide-forming) EC 1.7.1.15: nitrite reductase (NADH) EC 1.7.1.16: nitrobenzene nitroreductase EC 1.7.1.17: FMN-dependent NADH-azoreductase

=== Optical nonlinearity === Nonlinear optical materials are of great importance for ultrafast photonics and optoelectronics. Recently, the giant optical nonlinearities of graphene oxide (GO) has proven useful for a number of applications. For example, the optical limiting of GO is indispensable in the protection of sensitive instruments from laser-induced damage. And the saturable absorption can be used for pulse compression, mode-locking and Q-switching. Also, the nonlinear refraction (Kerr effect) is crucial for applications including all-optical switching, signal regeneration, and fast optical communications. An intriguing property of GO is that its electrical and optical properties can be tuned dynamically by manipulating the content of oxygen-containing groups through either chemical or physical reduction methods. The tuning of the optical nonlinearities has been demonstrated during the laser-induced reduction process through the continuous increase of the laser irradiance, and four stages of different nonlinear activities have been discovered, which may serve as promising solid state materials for novel nonlinear functional devices. Metal nanoparticles can greatly enhance the optical nonlinearity and fluorescence of graphene oxide.

MetaPred: A webserver for the prediction of cytochrome P450 isoforms responsible for metabolizing a drug molecule. The MetaPred server predicts metabolizing CYP isoforms of a drug molecule/substrate based on SVM models developed using CDK descriptors. This server is intended to help researchers working in the field of drug discovery. The effort also demonstrates that it is possible to develop free web servers in the field of cheminformatics. This may encourage other researchers to develop web servers for public use, leading to decreased cost of discovering new drug molecules. ToxiPred: A server for prediction of aqueous toxicity of small chemical molecules in T. pyriformis. KetoDrug: A user friendly web server for binding affinity prediction of ketoxazole derivatives and small chemical molecules against Fatty Acid Amide Hydrolase (FAAH). KiDoQ: A web server to serve researchers working in the field of designing inhibitors against dihydrodipicolinate synthase (DHDPS), a potential drug target enzyme of a unique bacterial DAP/Lysine pathway. GDoQ: GDoQ (Prediction of GLMU inhibitors using QSAR and AutoDock) is an open source platform for predicting inhibitors against Mycobacterium tuberculosis (M.Tb) drug target N-acetylglucosamine-1-phosphate uridyltransferase (GLMU) protein. This is a potential drug target involved in bacterial cell wall synthesis. This server uses molecular docking and QSAR strategies to predict inhibitory activity value (IC50) of chemical compounds for GLMU protein. ROCR: The ROCR is an R package for evaluating and visualizing classifier performance.

Sources: en.wikipedia.org

Supporting material

== Etymology == The term "Drosophila", meaning "dew-loving", is a modern scientific Latin adaptation from Greek words δρόσος, drósos, "dew", and φίλος, philos, "loving". The term "melanogaster", meaning "black belly", comes from Ancient Greek μέλας, mélas, "black", and γᾰστήρ, gastḗr, "belly".

Black Market Reloaded's popularity increased dramatically after the closure of Silk Road and Sheep Marketplace; however, in late November 2013, the owner of Black Market Reloaded announced that the website would be taken offline due to the unmanageable influx of new customers this caused. Sheep Marketplace, which launched in March 2013, was one of the lesser known sites to gain popularity with Silk Road's closure. Not long after those events, in December 2013, it ceased operation after two Florida men stole $6 million worth of users' Bitcoins.

== N == N-formylmethionine - N-formylmethionine leucyl-phenylalanine - N-methyl-D-aspartate receptor - N-methylaspartate - N-terminus - NADH - NADPH - NaKATPase - native state - nef gene product - neoplasm protein - Nernst equation - nerve - nerve growth factor - nerve growth factor receptor - nerve tissue protein - nerve tissue protein S 100 - nervous system - neurobiology - neurofilament protein - neurokinin A - neurokinin K - neurokinin-1 receptor - neurokinin-2 receptor - neuron - neuronal cell adhesion molecule - neuropeptide - neuropeptide receptor - neuropeptide Y - neuropeptide Y receptor - neuroscience - neurotensin - neurotensin receptor - neurotransmitter - neurotransmitter receptor - neutral theory of molecular evolution - neutron - neutron activation analysis - NF-kappa B - nicotinic receptor - nitrogen - nitroglycerine - Nobel Prize in Chemistry - non-competitive inhibition - nuclear lamina - nuclear localization signal - nuclear magnetic resonance - NMR - nuclear protein - nucleic acid - nucleic acid regulatory sequence - nucleic acid repetitive sequence - nucleic acid sequence homology - nucleon - nucleophile - nucleoside - nucleosome - nucleotide - nutrition

Aside from adult transgender people, CPA has also been used as a puberty blocker and hence as an antiandrogen and antiestrogen to suppress puberty in transgender adolescents, although GnRH modulators are primarily used and more effective for this purpose.

Sources: en.wikipedia.org

Frequently asked questions

What is AOD9604 derived from?

AOD9604 is a synthetic peptide based on a C-terminal segment of human growth hormone. It is manufactured by chemical peptide synthesis rather than extracted from human tissue. The sequence is often described as hGH fragment 176–191 or a close variant.

Is AOD9604 approved as a medicine?

It is not approved as a prescription drug in the United States or the European Union for any indication. Regulatory status can differ by country, and it is often sold as a research chemical or in unapproved products. Such products are not equivalent to an approved medicine.

Does AOD9604 raise IGF-1 levels?

In the studies reported so far, AOD9604 does not appear to act through the growth hormone receptor and has not shown the typical IGF-1 increase caused by full-length hGH. Human data are limited, so this remains an area of uncertainty. It should not be assumed to have the same effects as hGH.

Is AOD-9604 approved for medical use?

No. It is not approved as a therapeutic drug by major regulators. It is sold for research purposes in many settings, which is not the same as clinical approval.

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