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Testagen

Also known as KEDG peptide, Lys-Glu-Asp-Gly, lysyl-glutamyl-aspartyl-glycine

Khavinson synthetic tetrapeptide (KEDG) marketed as a male-reproductive bioregulator; essentially unstudied.

preclinical Hormonal & sexual research chemical

At a glance

Category
Hormonal & sexual
Status
research chemical
Route
in vitro in the published work; oral in the retail supplement form; subcutaneous or intramuscular for the grey-market injectable powder
Half-life
No published pharmacokinetics in any species. An unmodified tetrapeptide with free termini; survival in plasma is presumably a matter of minutes. All circulating figures are unsourced.
Onset
No validated onset time; there are no controlled human data on the time course of any effect
Molecular weight
Approximately 447 g/mol for the free tetrapeptide (Lys-Glu-Asp-Gly, calculated)
Sequence
Lys-Glu-Asp-Gly 12

Testagen is a synthetic tetrapeptide from the Khavinson bioregulator programme, sold as an oral supplement and as a lyophilised powder for injection and marketed as a testicular or male-reproductive bioregulator. Its identity as a defined peptide is unusually well confirmed for this family: a Khavinson-affiliated biophysics paper gives the sequence as Lys-Glu-Asp-Gly 1, and an unrelated materials-chemistry group independently synthesised 'testagen (KEDG)' as H-Lys-Glu-Asp-Gly-OH and characterised it as a copper corrosion inhibitor 2. It is not an approved medicine in the EU or US. A ClinicalTrials.gov search returns a single record, but it is for an unrelated transdermal testosterone product also called Testagen, not this peptide 6 - one of several name collisions in this corner of the market.

Doping status: Not listed by name; as a non-approved substance it falls under the S0 residual category and is therefore prohibited at all times

Checked against the WADA 2026 Prohibited List. For a specific product and country, Global DRO is the lookup athletes are expected to use — the List names substances, not brand names.

This is a short entry. There is little or no published research on this compound, so there is correspondingly little to report. Empty dosing or reconstitution sections mean no credible figures exist — not that they were left out.

Mechanism of action

Testagen is presented as one of the Khavinson 'directed synthesis' peptides - a short sequence said to be derived from the amino acid composition of a tissue extract, here the testis, and marketed as a bioregulator that restores the function of that organ. The proposed mechanism is the programme's standard one: the peptide is claimed to enter cell nuclei and bind promoter DNA to direct tissue-specific gene expression, with retail material adding specific but unsupported claims about steroidogenic gene expression and testosterone synthesis.

The one concrete published observation is that a fluorescently labelled Testagen penetrates the nucleus of cultured HeLa cells and, in vitro, quenches the fluorescence of labelled DNA oligonucleotides in a sequence-preferential way, alongside epithalon and pinealon 1. That is offered by the originating circle as evidence of sequence-specific DNA recognition. The standard objection applies: a four-residue peptide has no folded structure with which to make the several simultaneous contacts that sequence-specific recognition requires in every characterised biological system, weak preferential quenching of an oligonucleotide in a cuvette is not gene-selective regulation in a cell, and no route to selective targeting of the testis has been described. The gap between this biophysical observation and the marketed reproductive claims is the whole distance between a hypothesis and a mechanism.

What the research shows

Testagen is one of the most thinly documented members of the series. The entire indexed literature under the name is two papers - a Khavinson-affiliated study of nuclear penetration and DNA binding 1 and a materials-chemistry study of copper corrosion 2 - and neither is about reproduction, hormones or any clinical outcome 4. There is no controlled trial, no independent replication of a biological effect, and no evidence that Testagen raises testosterone or improves any reproductive parameter in a human being.

Research in humans

No controlled clinical trial or human outcome study was found 4. No human study has shown that Testagen affects testosterone, spermatogenesis or any reproductive measure; the reproductive and steroidogenic claims that circulate on retail pages are marketing, not findings. The nearest human-derived work is the use of cultured human HeLa cells to show that the labelled peptide can enter a nucleus 1 - a cell-biology observation, not a study of an effect in people.

Animal and lab research

No in vivo animal study of Testagen on reproductive endpoints was found under the name 4. The peptide's appearances in the literature are the in vitro DNA-binding work 1 and, outside biology entirely, its use as a synthesised model tetrapeptide in a corrosion-inhibition study 2.

Caveats. There is almost nothing to appraise. The two indexed papers do not test the marketed indication at all; one originates with the group that developed the peptide and the other is unrelated to its biological use. There is no independent biological replication, no dose-finding work, no pharmacokinetics, no toxicology and no reproductive-toxicity study - the last a striking gap for a product sold to act on the reproductive system.

What it is used for

  • Marketed and self-administered as a testicular or male-reproductive bioregulator, and for testosterone and fertility support - claims for which no controlled study exists 4
  • Characterised in vitro for nuclear penetration and DNA binding by the originating research circle 1
  • Used, unrelated to any biological purpose, as a synthesised model tetrapeptide in a copper corrosion-inhibition study 2

Dosing

Route
oral in the retail form; subcutaneous or intramuscular for the grey-market powder
  • There is no validated human dose: no dose-finding study, no maximum tolerated dose, no human pharmacokinetics and no dose-response curve 4.
  • The published work is in vitro and does not involve dosing an organism 12; there is nothing to scale from.
  • The milligram figures in circulating user protocols track the vial and capsule size the product is sold in, not any research finding. Left null rather than manufacturing a protocol.

These figures describe what the literature and published protocols report. They are not advice and not a dosing instruction.

Protocols

Bioregulator course (grey market)

user protocol — not validated

Source: vendor material and user protocols; no published basis

This is not a validated schedule. It is a pattern that circulates among users and sellers, reproduced because it is what people actually follow — not because it has been tested. No trial established these doses, this interval or this duration, and nobody is checking what is in the vial. Treat every number below as an assertion, not a finding.

Oral course1 to 3 capsules daily for about 10 to 30 days
Injectable course (research-chemical powder)a few milligrams per day by subcutaneous or intramuscular injection for 10 to 20 days
Repeatonce or twice a year in some vendor instructions

No publication supports any dose for Testagen; the two indexed papers are in vitro and involve no dosing of an organism 12. The circulating figures follow the capsule count and vial size. The retail oral capsule and the injected research-chemical powder are different preparations sold under the same name.

Schedules are reproduced as their source states them. Units, IU and milligrams explains why the figures are not interchangeable between products.

Reconstitution

Vial sizes
10 mg, 20 mg (lyophilised powder, research chemical); also oral capsules in the retail supplement line, a different preparation
Solvent
bacteriostatic water (0.9% benzyl alcohol); sterile water only if used within the same session
Storage
Supplier guidance: powder at 2-8 °C short term or -20 °C long term, protected from light; reconstituted at 2-8 °C for roughly 2-4 weeks. These are handling conventions, not pharmacopoeia specifications.

Let the diluent run down the vial wall, swirl and do not shake; discard if cloudy. Grey-market short peptides are regularly mislabelled or underdosed, and self-issued certificates of analysis cannot be independently verified.

Work it out for Testagen

Safety

Side effects

  • Not systematically documented, because no systematic safety research exists - neither indexed paper is a safety or tolerability study 4. An empty side effect profile reflects absence of investigation, not demonstrated safety
  • No toxicology, carcinogenicity or reproductive-toxicity study appears in the indexed literature, despite the product being marketed to act on the reproductive system
  • Reported at user level only, uncontrolled and unverifiable: injection site reactions with the injectable form

Do not use if

  • Pregnancy and breastfeeding - no data
  • Children and adolescents - no data, and a product marketed to act on reproductive-hormone pathways has never been studied during development
  • Hormone-sensitive conditions, including prostate cancer - no data; the marketed mechanism concerns steroidogenesis, and effects on androgen pathways have never been characterised
  • Hypersensitivity to the peptide or, for injectable use, to benzyl alcohol in the diluent

Interactions

Not studied. No interaction data of any kind exist for this product 4. Any theoretical interaction with testosterone therapy or other hormonal treatment is unexamined.

Sources