Testagen

Mechanism of action

Proposed to support testis-axis aging and male reproductive decline under the Khavinson-framework tissue-specific gene-expression hypothesis. Molecular validation minimal.

Primary uses

• Testis-axis aging support (Russian nutraceutical positioning)
• Male reproductive aging adjunct (anecdotal / Russian clinical use)

Typical dosing

Regulatory status

Not FDA- or EMA-approved. Russian nutraceutical status only.

Status as of this entry's last review, October 4, 2026. Approvals, compounding rules and sport rules change; the regulatory tracker is checked more often.

What we checked

Two papers indexed on PubMed name testagen, and several more test its sequence under other descriptions. This section records the identity, the regulatory status on the date below, what those papers found, and every search we ran.

Identity, computed

Two papers tie the name to the sequence. A 2011 paper from the Khavinson group lists testagen as Lys-Glu-Asp-Gly beside epitalon and pinealon (Fedoreyeva et al., 2011), and a 2025 paper in Molecules names its test compound testagen (KEDG). The same tetrapeptide appears in Russian papers from 2008 to 2013 as a synthetic peptide built from the amino-acid make-up of anterior-pituitary extract, so the literature attaches it to two tissues. An earlier version of this entry gave the formula C17H30N6O8 (446.46), which no arrangement of these four amino acids produces, and said the peptide was shared with Ventfort; both were corrected on October 4, 2026.

Regulatory status, read October 4, 2026

Drugs@FDA: 0 records for “testagen”. EMA medicines list: 0 records for “testagen”. Run for semaglutide, the same queries return 6 and 5 records (and the registry search 84 trials), so a zero here is an absence, not a broken search. Not named on the WADA 2026 and 2027 Prohibited Lists. As a substance with no current approval for human therapeutic use, it falls under section S0 (non-approved substances), which is prohibited at all times; the lists were read on September 27, 2026.

What the maker or sellers claim

Claim, from Russian sellers: testagen supports the aging testis and male reproductive function. No indexed study tests it in testis tissue or in men.

About the family, not this compound

The Khavinson peptides are di-, tri- and tetrapeptides developed at the Saint Petersburg Institute of Bioregulation and Gerontology, most first isolated from animal tissue extracts and later made synthetically. The group proposes that they reach the cell nucleus and change gene expression in the tissue they are named for. Nearly all of the indexed work comes from that group and its collaborators.

A 2023 modelling study from the same group docked 26 of these short peptides, including AED, EDL, EDG and KEDG, into the amino-acid and peptide transporters LAT1, LAT2 and PEPT1, and proposed those transporters as their route into cells (Khavinson et al., 2023). It is a computer model of binding, not a measurement in cells, and it says nothing about any one product's effects.

What the studies of Lys-Glu-Asp-Gly show

Three studies in chickens describe KEDG as the anterior-pituitary peptide. In chicks whose pituitary was removed at hatching, 40 days of KEDG with its posterior-pituitary partner AEDG raised thyrotropin and thyroid hormones and restored thyroid structure (Kuznik et al., 2008). A follow-up found the same normalising effect in young chickens and old hens, weaker in the hens (2011), and a 2013 study found KEDG restored thymus structure in such birds more strongly than AEDG. These are animal results from one research network, and none involves the testis.

In human HeLa cells, fluorescently labelled testagen entered the cytoplasm, nucleus and nucleolus, and unlabelled testagen changed the fluorescence of labelled DNA fragments in a test tube (Fedoreyeva et al., 2011); the group reads this as a route to acting on genes, which the paper does not show. The 2025 Molecules paper is chemistry: KEDG slowed corrosion of copper in salt water by about 86% by coating the metal. It says nothing about biology. The papers are in the References.

What we looked for and did not find

No human study, no study in testis or other reproductive tissue, no pharmacokinetic data, no registry record and no dose from a controlled study. The one ClinicalTrials.gov match is a different product: a transdermal testosterone spray branded Testagen (NCT02733133), never recruited.

References

1. [review] Khavinson VK, et al. "Peptide bioregulation of endocrine function and aging." Adv Gerontol, 2012;25:11-23 (Russian).
2. [review] Anisimov VN, Khavinson VK. "Peptide bioregulation of aging: results and prospects." Biogerontology, 2010;11:139-149. PMID: 19830585.
3. [pubmed] Dobriţescu A, et al. "The Inhibitory Effect and Adsorption Properties of Testagen Peptide on Copper Surfaces in Saline Environments: An Experimental and Computational Study." Molecules, 2025;30(15). PMID: 40807317.
4. [pubmed] Kuznik BI, et al. "[Effects of hypophyseal Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly synthetic peptides on immunity, hemostasis, morphology and functions of the thyroid gland in neonatally hypophysectomized chicken and one-year-old birds]." Patol Fiziol Eksp Ter, 2010:14-8. PMID: 20731122.
5. [pubmed] Fedoreyeva LI, et al. "Penetration of short fluorescence-labeled peptides into the nucleus in HeLa cells and in vitro specific interaction of the peptides with deoxyribooligonucleotides and DNA." Biochemistry (Mosc), 2011;76(11):1210-9. PMID: 22117547.
6. [pubmed] Pateyk AV, et al. "Effect of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on the morphology of the thymus in hypophysectomized young and old birds." Bull Exp Biol Med, 2013;154(5):681-5. PMID: 23658898.
7. [pubmed] Kuznik BI, et al. "Effects of peptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on hormonal activity and structure of the thyroid gland in hypophysectomized young chickens and old hens." Bull Exp Biol Med, 2011;150(4):495-9. PMID: 22268052.
8. [pubmed] Kuznik BI, et al. "Effect of tetrapeptides Lys-Glu-Asp-Gly and Ala-Glu-Asp-Gly on the structure and function of the thyroid gland in neonatally hypophysectomized chickens." Bull Exp Biol Med, 2008;145(1):104-7. PMID: 19024016.

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