This is a working overview of AOD-9604, written for readers who want more than a one-paragraph summary but less than a textbook.
This page was last updated on 2026-01-06 and is reviewed periodically as new material appears.
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.
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.
AOD-9604 is a synthetic peptide whose structure corresponds to a C-terminal segment of human growth hormone. It is often described as hGH fragment 176-191, a 16-amino-acid sequence. The peptide was designed to isolate a region of hGH associated with fat metabolism while avoiding the full hormone's growth-promoting actions. Laboratory and commercial materials typically present it as a lyophilized powder for research use. Its identity is defined by amino acid sequence, not by a single brand.
The fragment includes residues that can form an internal disulfide bond between two cysteine positions. This structural feature can influence how the peptide folds and how stable it is in solution. AOD-9604 differs from full-length hGH in size and receptor interactions; it does not contain the entire growth hormone sequence. Published descriptions sometimes use slightly different residue numbering, so sequence information should be checked against primary sources. The molecule is small compared with intact hGH, which affects analytical detection and purification approaches.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Peptide fragment | Corresponds to hGH residues 176-191 |
| Common synonyms | AOD9604, hGH 176-191 | Also written as AOD-9604 |
| Typical form | Lyophilized powder | Often supplied in sealed vials |
| Solubility | Water-soluble | Dissolves in aqueous buffers |
| Regulatory status | Not approved as drug | Banned in sport; varies by country |
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.
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.
Commercial AOD-9604 may vary in purity, counterion content, and residual moisture. Certificates of analysis often report HPLC purity, mass confirmation, and appearance, but testing methods differ between suppliers. Independent verification is sometimes used because labeled content may not match actual peptide amount. Stability under different pH and temperature conditions is not fully standardized across studies. Researchers generally treat lyophilized material as the reference form for weighing and reconstitution. Moisture content can affect accurate mass measurement.
AOD-9604 is typically supplied as a lyophilized white to off-white powder. In this form, it is relatively stable when kept cool, dry, and protected from light. Common storage recommendations place it at −20 °C or below for long-term retention. Reconstituted solutions are less stable and are often kept at 2–8 °C for short periods. Freeze-thaw cycles should be minimized because they can promote aggregation or loss of peptide content. Vials are usually sealed under inert gas to reduce oxidation.
Identity and purity are commonly checked with reversed-phase high-performance liquid chromatography and mass spectrometry. RP-HPLC separates the peptide from related impurities and can estimate purity by peak area. Mass spectrometry confirms molecular mass and helps detect sequence variants or truncations. Some laboratories use amino acid analysis or peptide mapping for additional characterization. No single method proves biological activity; these techniques establish chemical identity and purity only. They also require suitable reference standards for confident comparison.
Some have argued that there is little evidence to indicate any benefit to using bodybuilding protein or amino acid supplements. A 2005 overview concluded that "[i]n view of the lack of compelling evidence to the contrary, no additional dietary protein is suggested for healthy adults undertaking resistance or endurance exercise". In contrast, a 2018 systematic review, meta-analysis and meta-regression concluded that, “Dietary protein supplementation significantly enhanced changes in muscle strength and size during prolonged RET in healthy adults.“ (RET is an abbreviation for resistance exercise training.) Instant breakfast Protein bar "Dietary Supplement Health and Education Act of 1994". U.S. Food and Drug Administration. 4 February 2020. Archived from the original on June 2, 2009.
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Sources: en.wikipedia.org
Antibody–drug conjugates or ADCs are a class of bioconjugates and immunoconjugates. ADCs are composed of an antibody linked to a cytotoxic (anticancer) "payload" or drug. Among treatment options for cancer, chemotherapy is most widely used. Its main limitation is low target specificity. Unlike chemotherapy, ADCs target tumor cells while sparing healthy cells. As of 2019, some 56 pharmaceutical companies were developing ADCs. ADCs combine the targeting properties of monoclonal antibodies with the cancer-killing capabilities of cytotoxic drugs, designed to discriminate between healthy and diseased tissue.
DNA usually occurs as linear chromosomes in eukaryotes, and circular chromosomes in prokaryotes. The set of chromosomes in a cell makes up its genome; the human genome has approximately 3 billion base pairs of DNA arranged into 46 chromosomes. The information carried by DNA is held in the sequence of pieces of DNA called genes. Transmission of genetic information in genes is achieved via complementary base pairing. For example, in transcription, when a cell uses the information in a gene, the DNA sequence is copied into a complementary RNA sequence through the attraction between the DNA and the correct RNA nucleotides. Usually, this RNA copy is then used to make a matching protein sequence in a process called translation, which depends on the same interaction between RNA nucleotides. In an alternative fashion, a cell may copy its genetic information in a process called DNA replication. The details of these functions are covered in other articles; here the focus is on the interactions between DNA and other molecules that mediate the function of the genome.
The FDA reviews commercially available test kits and their associated medical claims to ensure safety and efficacy before products are cleared or approved for use. The regulatory landscape for laboratory developed tests (LDTs) has been evolving significantly. On May 6, 2024, the FDA issued a final rule significantly modifying its approach to oversight of laboratory-developed tests, amending regulations to clarify that in vitro diagnostic products (IVDs) are devices under the Federal Food, Drug, and Cosmetic Act, including when manufactured by a laboratory. The final rule includes a policy under which FDA would phase out enforcement discretion for LDTs over a four-year period. The phaseout policy consists of five stages, starting May 6, 2024. DTC tests are specifically noted as having never been subject to enforcement discretion, meaning compliance with FDA requirements has always been expected for consumer-facing diagnostic tests. However, on April 17, 2025, a federal court blocked FDA's final rule on LDTs, creating uncertainty about the regulatory future. LDTs continue to be governed by CMS under CLIA oversight, but the long-term regulatory framework remains unsettled.
study of complex formation in supramolecular systems – organized ensembles surfactants and macrocyclic ligands; study of coordination compounds of iron (III) and manganese (II) for magnetic resonance imaging; obtaining new types of hybrid organic-inorganic functional materials based on nanoscale hyperbranched structures. Results of these studies are of basic value in the area of coordination chemistry, bioinorganic chemistry, chemistry of nanomaterials, pharmaceutical chemistry. Proposed model and physio-chemical basis of self-assembly of nanoscale of hyperbranched polymers, set new approaches to understanding the mechanisms of gene transfection and targeted drug delivery.
Sources: en.wikipedia.org
AOD-9604 is a synthetic peptide fragment of human growth hormone, corresponding to amino acids 176-191. It is studied for potential effects on fat metabolism, but it is not approved as a drug in most countries. Its exact mechanism remains under investigation.
No, it is a small fragment of the full growth hormone protein. It does not appear to stimulate growth or increase growth hormone levels in the same way. Its actions are thought to be more limited to metabolic pathways.
Regulatory status varies. It is not approved for medical use in the United States or many other countries. It is banned in sport by WADA, and its sale as a supplement or research chemical may be subject to legal restrictions.
It is a synthetic peptide based on a C-terminal fragment of human growth hormone. It is commonly referred to as hGH fragment 176-191 and is studied for metabolic effects rather than growth effects.