peptide research comes up often in conversation and rarely with the context attached. Here we lay out the basics in order, then work through the practical considerations.
Last reviewed on 2026-05-20. Where a claim depends on a specific study, the study is described rather than over-claimed.
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.
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 has been investigated mainly in the context of body fat and metabolic endpoints. Some early animal and small human studies reported changes in fat mass or lipid markers, but findings were not uniform. Larger, well-controlled trials that would establish efficacy are lacking in the public literature. As a result, claims about weight loss or metabolic benefit remain investigational rather than established. The distinction between a research finding and a proven clinical outcome is central to discussing this peptide.
| Property | Value | Notes |
|---|---|---|
| Common name | AOD-9604 | Development code used in scientific literature. |
| Chemical class | Synthetic peptide | Fragment of human growth hormone. |
| Amino acid length | 16 residues | Matches hGH region 176-191. |
| Appearance | White to off-white powder | Typical lyophilized peptide solid. |
| Solubility | Soluble in water | Dissolves in aqueous media; exact behavior depends on salt form. |
Regulatory status: AOD-9604 is not approved as a therapeutic drug in the United States, European Union, or other major markets. It is listed by the World Anti-Doping Agency as a prohibited substance in sport, specifically under growth hormone fragments. Many jurisdictions restrict its sale for human consumption. Products marketed online may not meet pharmaceutical quality standards. The legal status varies by country and often depends on whether the material is presented as a research chemical, supplement, or drug.
Detection and characterization of AOD-9604 in research and anti-doping settings typically rely on mass spectrometry coupled with liquid chromatography. These methods can identify the peptide by its mass and fragmentation pattern. Immunoassays may also be used in some screening contexts, but they can cross-react with related peptides. Because the molecule is small and may be present at low concentrations, sample preparation and method validation are important. Confirmatory analysis usually requires comparison with a certified reference standard.
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.
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.
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.
The compound has been studied as a potential treatment for obesity and related metabolic conditions. Published trials have examined changes in body weight, fat mass, and safety markers over limited durations. Results have been mixed or modest, and no large-scale outcome trials are established. Regulatory agencies in several countries have not approved it as a therapeutic drug. Some commercial products have been marketed outside regulated pharmaceutical channels, which raises questions about quality and claims.
In the scientific literature, AOD-9604 appears in reviews of growth hormone fragments and in discussions of peptide-based metabolic research. Some sources distinguish it from growth hormone itself, while others group it with compounds marketed for weight management. The evidence base is small compared with approved obesity medications. Questions about long-term efficacy and clinical relevance remain open, and independent replication of key findings is limited. Most published reports are early-stage and exploratory.
== Further reading == Brandoni, Diego; Scillato Yané, Gustavo J.; Miño Boilini, Ángel R.; Favotti, Emmanuel (2016). "Los Tardigrada (Mammalia, Xenarthra) de Argentina: diversidad, evolución y biogeografía" (PDF). Contribuciones del MACN. _: 263–274. Retrieved 2018-10-08. Cuvier, G. (1796): Notice sur le squelette d'une très grande espèce de quadrupède inconnue jusqu'à présent, trouvé au Paraguay, et déposé au cabinet d'histoire naturelle de Madrid. Magasin encyopédique, ou Journal des Sciences, des Lettres et des Arts (1): 303–310; (2): 227–228. De Iuliis, G. & Cartelle, C. (1999): A new giant megatheriine ground sloth (Mammalia: Xenarthra: Megatheriidae) from the late Blancan to early Irvingtonian of Florida. Zool. J. Linn. Soc. 127(4): 495–515. Harrington, C.R. (1993): Yukon Beringia Interpretive Center - Jefferson's Ground Sloth. Retrieved 2008-JAN-24. Hogan, C.M. (2008): Cueva del Milodon, Megalithic Portal. Retrieved 2008-APR-13 Kurtén, Björn and Anderson, Elaine (1980): Pleistocene Mammals of North America. Columbia University Press, New York. ISBN 0-231-03733-3 McKenna, Malcolm C. & Bell, Susan K. (1997): Classification of Mammals Above the Species Level. Columbia University Press, New York. ISBN 0-231-11013-8 Nowak, R.M. (1999): Walker's Mammals of the World (Vol. 2). Johns Hopkins University Press, London. White, J.L. (1993): Indicators of locomotor habits in Xenarthrans: Evidence for locomotor heterogeneity among fossil sloths. Journal of Vertebrate Paleontology, 13(2): 230–242. White, J.L.; MacPhee, R.D.E. (2001).
==== Illegal marketing of gabapentin for off-label uses settlement (2004) ==== In 1993, the Food and Drug Administration (FDA) approved gabapentin only for treatment of seizures. Warner–Lambert, which merged with Pfizer in 2000, used continuing medical education and medical research, sponsored articles about the drug for the medical literature, and alleged suppression of unfavorable study results, to promote gabapentin. Within five years, the drug was being widely used for off-label uses such as treatment of pain and psychiatric conditions. Warner–Lambert admitted to violating FDA regulations by promoting the drug for pain, psychiatric conditions, migraine, and other unapproved uses. In 2004, the company paid $430 million in one of the largest settlements to resolve criminal and civil health care liability charges. It was the first off-label promotion case successfully brought under the False Claims Act. A Cochrane review concluded that gabapentin is ineffective in migraine prophylaxis. The American Academy of Neurology rates it as having unproven efficacy, while the Canadian Headache Society and the European Federation of Neurological Societies rate its use as being supported by moderate and low-quality evidence.
=== China === In July 2007, officials of the People's Republic of China seized US-produced pork for containing ractopamine residues. Further shipments of Canadian ractopamine-fed pork were seized in September 2007. In June 2019, customs inspectors in China detected ractopamine in a shipment of Canadian pork products destined for Chinese consumption. The Chinese government thereupon suspended not only pork, but also beef imports from Canada. Canadian Agriculture Minister Marie-Claude Bibeau stated that the CRFPCP certificate was a forgery and called in the RCMP, while Canadian Public Safety Minister Ralph Goodale stressed that the federal government would vigorously defend Canadian meat producers. It was also revealed that the Canadian Cattlemen's Association said in a statement that "We are fully confident in our meat production systems in Canada and the safeguards we have in place." Meanwhile, holes were found in the CRFPCP programme because the meat packer at the centre of the controversy was a chilled butcher shop only.<what> It was disclosed on 3 July that the Chinese authorities had discovered 188 falsified CRFPCP certificates.
However, Ukrainian presidential advisor Mykhailo Podolyak said Kyiv had "nothing to do" with the attack and said Russian anti-Kremlin guerrilla groups were responsible. The Liberty of Russia Legion and the Russian Volunteer Corps (RVC) later claimed responsibility for the attack, with the Legion claiming to have taken the border town of Kozinka and reached Graivoron. Evacuations were ordered in nine villages and a counter-terrorist operation were ordered in the affected areas by the regional government, while the Russian military dispatched fighter jets and artillery to the scene. The Institute for the Study of War later assessed that two "all-Russian pro-Ukrainian" groups had crossed the border with tanks, armoured personnel carriers and other armoured vehicles. Attacks were also reported on offices of the Interior Ministry and the FSB in Belgorod city. Gladkov later said 13 civilians were injured, damage was recorded in 29 houses and three cars were damaged and electricity was lost in 14 settlements. The NATO Parliamentary Assembly issued a declaration recognizing Russian atrocities in Ukraine as "genocide" according to the head of the Ukrainian delegation Yehor Cherniev. He said that the declaration included support for an international tribunal for Russian war crimes, helping Ukraine win the war and a commitment to help restore the country's territories by implementing more sanctions.
Sources: en.wikipedia.org
Acid-catalyzed hydrolysis of esters is also an equilibrium process – essentially the reverse of the Fischer esterification reaction. Because an alcohol (which acts as the leaving group) and water (which acts as the nucleophile) have similar pKa values, the forward and reverse reactions compete with each other. As in transesterification, using a large excess of reactant (water) or removing one of the products (the alcohol) can promote the forward reaction.
== Function == Although the majority of VWA-containing proteins are extracellular, the most ancient ones present in all eukaryotes are all intracellular proteins involved in functions such as transcription, DNA repair, ribosomal and membrane transport and the proteasome. A common feature appears to be involvement in multiprotein complexes. Proteins that incorporate vWF domains participate in numerous biological events (e.g. cell adhesion, migration, homing, pattern formation, and signal transduction), involving interaction with a large array of ligands.
== Structure == The non-fluid parts of the interstitium are predominantly collagen types I, III, and V; elastin; and glycosaminoglycans, such as hyaluronan and proteoglycans, that are cross-linked to form a honeycomb-like reticulum. Collagen bundles of the extracellular matrix form scaffolding with a high tensile strength. Interstitial cells (e.g., fibroblasts, dendritic cells, adipocytes, interstitial cells of Cajal and inflammatory cells, such as macrophages and mast cells), serve a variety of structural and immune functions. Fibroblasts synthesize the production of structural molecules as well as enzymes that break down polymeric molecules. Such structural components exist both for the general interstitium of the body, and within individual organs, such as the myocardial interstitium of the heart, the renal interstitium of the kidneys, and the pulmonary interstitium of the lungs. The interstitium in the submucosae of visceral organs, the dermis, superficial fascia, and perivascular adventitia are fluid-filled spaces supported by a collagen bundle lattice. Blind end, highly permeable, lymphatic capillaries extend into the interstitium. The fluid spaces communicate with draining lymph nodes, although they do not have lining cells or structures of lymphatic channels. Interstitial fluid entering the lymphatic system becomes lymph, which is transported through lymphatic vessels until it empties into the microcirculation and the venous system.
Sources: en.wikipedia.org
AOD-9604 is a synthetic peptide fragment of human growth hormone. It corresponds to the C-terminal region known as hGH 176-191 and is studied for metabolic effects. It is not an approved therapeutic drug.
No. It contains only a small portion of the human growth hormone sequence. The full hormone has 191 amino acids and many additional actions that the fragment does not share.
The name refers to the amino acid positions in the human growth hormone chain. The fragment spans residues 176 through 191 at the C-terminal end. This naming convention helps distinguish it from full-length hGH.
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.