A practical reference on regulatory status: what it is, how it behaves, what the literature reports, and where the honest uncertainties sit.
Reviewed 2026-07-08. Anything still debated is marked as such rather than presented as settled.
AOD-9604 is a synthetic peptide whose sequence is modeled on the C-terminal region of human growth hormone. Published descriptions commonly place it as a modified fragment corresponding to hGH amino acids 176–191, with a tyrosine residue added or retained at the N-terminus to support detection and handling. It is not intact growth hormone and lacks the full receptor-binding architecture of the parent protein. The molecule was developed as a research candidate for metabolic studies rather than as a replacement for growth hormone therapy. Its identity is defined by its amino acid sequence rather than by any single commercial preparation.
AOD-9604 drew attention in the 1990s and 2000s as a potential anti-obesity agent. Early work explored both injectable and oral routes, which is unusual for a peptide of this size. Animal studies reported changes in fat metabolism without the growth-promoting or insulin-like effects associated with full-length growth hormone. Subsequent human trials produced mixed or modest results, and the compound did not obtain regulatory approval for weight management in major markets. It remains known mainly through research literature, sports anti-doping listings, and non-approved supplement advertising.
AOD-9604 is prohibited in sport by the World Anti-Doping Agency under the peptide hormone class. Its presence in a sample can be detected through mass spectrometry-based methods, although the exact assay depends on the laboratory. In research settings, material is often supplied as a lyophilized powder for reconstitution. Buyers and researchers should note that products labeled AOD-9604 may vary in purity and actual peptide content. Analytical certificates and independent testing are common ways to verify identity, but no global harmonized standard exists for all commercial lots.
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.
| Property | Value | Notes |
|---|---|---|
| Molecular class | Synthetic peptide | Fragment analog of human growth hormone |
| Sequence basis | hGH 176–191 region | Modified C-terminal fragment |
| Common synonyms | AOD-9604; AOD9604; hGH fragment | Research and trade names vary |
| Regulatory status | Not approved as a drug | Prohibited in competitive sport |
| Research code | AOD9604 | Used in scientific and patent literature |
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.
In laboratory settings, AOD-9604 is commonly supplied as a lyophilized powder and stored cold to limit degradation. Reconstituted solutions are typically kept refrigerated or frozen, depending on the buffer and concentration, and protected from repeated freeze-thaw cycles. Stability can be influenced by pH, temperature, and the presence of proteases. Purity is usually assessed by high-performance liquid chromatography and mass spectrometry. These practices support reproducibility, but they do not imply safety or efficacy for any human use.
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.
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.
=== Activation === Asparagine endopeptidase is synthesized as an inactive zymogen. AEP and other cysteine peptidase are activated when pH changes from neutral to acidic. It undergoes autoproteolytic maturation for catalytic activation. It appears to be autocatalytically cleaved after asparagine or aspartate residue. Activation begins at pH 4.5. The chemical structure at this point shows that breaks which occurs at pH 4.5 can be healed under the basic crystallization conditions. C-terminal fragments (≈13 kDa) generated during autoproteolysis can gradually re-ligated to form the proenzyme when the pH is increased towards pH 7.5, which means that proteolytic activation of AEP can be reversible.
Plasma protein binding refers to the degree to which medications attach to blood proteins within the blood plasma. A drug's efficacy may be affected by the degree to which it binds. The less bound a drug is, the more efficiently it can traverse or diffuse through cell membranes. Common blood proteins that drugs bind to are human serum albumin, lipoprotein, glycoprotein, and α, β‚ and γ globulins.
== Medical uses == EDE, a long-acting estrogen, was used in combination with EB, a short-acting estrogen, and TEBH, a long-acting androgen/anabolic steroid, in menopausal hormone therapy in perimenopausal, postmenopausal, hypogonadal, and oophorectomized women, as well as for suppression of lactation in postpartum women.
Sources: en.wikipedia.org
Amitriptyline was developed by the American pharmaceutical company Merck in the late 1950s. In 1958, Merck approached several clinical investigators proposing to conduct clinical trials of amitriptyline for schizophrenia. One of these researchers, Frank Ayd, instead, suggested using amitriptyline for depression. Ayd treated 130 patients and, in 1960, reported that amitriptyline had antidepressant properties similar to another, and the only known at the time, tricyclic antidepressant imipramine. Following this, the US Food and Drug Administration approved amitriptyline for depression in 1961. In Europe, due to a quirk of the patent law at the time allowing patents only on the chemical synthesis but not on the drug itself, Roche and Lundbeck were able to independently develop and market amitriptyline in the early 1960s. According to research by a historian of psychopharmacology David Healy, amitriptyline became a much bigger selling drug than its precursor imipramine because of two factors. First, amitriptyline has a much stronger anxiolytic effect. Second, Merck conducted a marketing campaign raising clinicians' awareness of depression as a clinical entity. Amitriptyline is no longer sold under the brand name Elavil.
The standard botanical author abbreviation Tswett is applied to plants that he described. Ostrowski, W (1968). "Michael S. Tswett—inventor of column chromatography (On the occasion of 65th anniversary of his lecture on the column chromatography technique)". Folia Biol. (Krakow). Vol. 16, no. 4. pp. 429–48. PMID 4885242. R. Willstätter, A. Stoll, Untersuchungen über Chlorophyll, Springer, Berlin (1913) Biography of Mikhail S. Tsvet (pdf, in German) Mikhail S. Tsvet: Physical chemical studies on chlorophyll adsorptions Berichte der Deutschen botanischen Gesellschaft 24, 316–323 (1906)
Selenium has six natural isotopes that occur in significant quantities, along with the trace isotope 79Se, which occurs in minute quantities in uranium ores. Five of these isotopes are stable: 74Se, 76Se, 77Se, 78Se, and 80Se. The last three also occur as fission products, along with 79Se, which has a half-life about 330,000 years, and 82Se, which has the very long half-life of 8.76×1019 years as it decays via double beta decay to krypton-82 and for practical purposes can be considered to be stable. There are 23 other unstable isotopes that have been characterized, the longest-lived after 79Se being 75Se with its half-life 119.78 days, 72Se at 8.40 days, and 73Se at 7.15 hours. The others are all under an hour and most do not exceed 38 seconds.
=== Clinical studies === Monotherapy The efficacy and safety of gemigliptin monotherapy were evaluated in two blinded placebo controlled studies and one blinded active-controlled study. A phase II study (study identifier: LG-DPCL002) of gemigliptin was conducted in a randomized, blinded, placebo-controlled, parallel group design with three doses of 50, 100, and 200 mg qd for the purpose of finding a dose responsiveness and an optimal dose in patients with T2DM. The mean changes of HbA1c at week 12 from the baseline were –0.98%, –0.74%, –0.78% (when adjusted with placebo data, –0.92%, –0.68%, and –0.72%) at 50, 100, and 200 mg, respectively. Among the effective doses obtained from the phase II study in patients with T2DM, the 50 mg dose showed a similar efficacy as the 100 and 200 mg doses, within the maximum safety margin. Similar findings were reported from two phase III studies. Patients were randomized to receive gemigliptin, either a 50 mg qd (n=90) or a placebo (n=92) for 24 weeks (study identifier: LG-DPCL005; ClinicalTrials.gov registration number: NCT01601990). The placebo-subtracted changes from baseline in HbA1c were reported to be −0.71% (95% confidence interval [CI], −1.04 to −0.37) with gemigliptin 50 mg. In addition, a 28-week open-label extension study was designed to evaluate the long-term safety and efficacy of gemigliptin. Among 165 patients who consented to participate in the extension period of study LG-DPCL005, 158 patients (96%) completed their treatments for 52 weeks.
Sources: en.wikipedia.org
No. It is a synthetic peptide fragment modeled on part of human growth hormone, not the full hormone. It does not contain the complete sequence or receptor-binding regions of hGH.
It was investigated in clinical trials for obesity, but it did not receive approval for that use in major markets. Results were generally modest or mixed, and it remains an experimental compound.
WADA lists it as a prohibited peptide hormone. Its use can be detected by laboratory methods, and athletes are subject to sanctions if it is found in samples.
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.