Cortagen
Also known as AEDP peptide, Ala-Glu-Asp-Pro, alanyl-glutamyl-aspartyl-proline
Khavinson tetrapeptide derived from the amino acid profile of Cortexin, with no independent evidence.
At a glance
- Category
- Neuro & cognition
- Status
- research chemical
- Route
- intramuscular, intraperitoneal and subcutaneous in the published animal work; oral or sublingual in the capsule form of the bioregulator line
- Half-life
- No published pharmacokinetics in any species. A tetrapeptide with free termini and no protective modification - no D-amino acids, no cyclisation, no N-methylation, no amidation - so survival in plasma is presumably a matter of minutes. All circulating half-life figures are unsourced.
- Onset
- No validated onset time; there are no controlled human data on the time course of any effect
- Molecular weight
- Approximately 431 g/mol for the free tetrapeptide. No independently determined value from a published characterisation was found.
- Sequence
- Ala-Glu-Asp-Pro
As far as can be established, synthetic Cortagen is not a registered medicine anywhere. Capsule products in the Russian Cytomax and Cytogen bioregulator lines are registered as food supplements (BAD), a notification regime with no efficacy assessment - which is not approval as a medicine. PeptideX has not been able to open the Russian register from outside Russia to confirm this, so the registration should be read as an unverified claim rather than an established fact. No EMA or FDA approval; outside Russia traded exclusively as a research chemical. The whole indexed literature is 15 PubMed records 8, none of them a clinical trial.
Doping status: Not listed by name; as a non-approved substance it falls under the S0 residual category and is 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
Cortagen sits in the same programme as Epitalon, Pinealon and Thymalin: Khavinson's group at the St Petersburg Institute of Bioregulation and Gerontology obtained it by 'directed synthesis' from amino acid analysis of Cortexin, the crude bovine cortex extract, and proposed it as the active constituent of that extract. The relationship of Cortagen to Cortexin is the same as that of Epitalon to Epithalamine.
The proposed mechanism is the standard bioregulator doctrine: a short peptide derived from an organ is said to enter cell nuclei, bind complementarily to promoter DNA and direct tissue-specific gene expression in that same organ. The specific criticisms made in the Epitalon and Pinealon entries apply here unchanged. A four-residue peptide, chemically indistinguishable from ordinary proteolytic breakdown material found throughout the body, has no described route to selective organ targeting, and sequence-specific DNA recognition in biology requires a folded domain making several simultaneous contacts - not a linear tetramer. This is a hypothesis, and it has never been independently tested.
The most concrete published claim is a 2004 microarray study reporting that Cortagen altered gene expression in mouse heart 5 - which, if taken at face value, is an odd result for a peptide advertised as cortex-specific, and rather undermines the tissue-specificity premise it was meant to support.
What the research shows
Cortagen's evidence base consists of about a dozen PubMed-indexed papers, essentially all from Khavinson's group or affiliated Russian laboratories, published in a small set of journals (Bulletin of Experimental Biology and Medicine, Doklady Biological Sciences, Advances in Gerontology, Neuroendocrinology Letters). There is no independent replication of any finding, no controlled human trial, and no Western involvement of any kind. There is no basis for stating that Cortagen improves cognition, repairs nerves or protects the brain in humans.
Research in humans
No controlled clinical trial of synthetic Cortagen was found. Claims about nerve regeneration and cardiovascular parameters in humans circulate in secondary and vendor material, sometimes with precise figures such as a 27% increase in fibre growth rate and a 40% increase in conduction velocity; these numbers trace to Russian animal work on sciatic nerve regeneration 1 rather than to a human trial, and repeating them as human results is a misattribution.
Animal and lab research
Reported effects, all from the originating group: acceleration of sciatic nerve regeneration in rats after injury, with improved conduction 1; a delayed effect on restoration of injured nerve function 3; altered gene expression in mouse heart by microarray 5; tissue-specific effects in organ culture 2; and effects on interleukin-2 gene expression and macrophage activity in the immunology papers where Cortagen appears alongside other short peptides 46.
Caveats. Single research group with a direct interest in the compound; small sample sizes; no blinding described; no protocol registration; outcome measures selected without pre-specification; publication in journals with limited external scrutiny, much of the primary work in Russian. Several studies test Cortagen together with other bioregulator peptides, which makes the contribution of AEDP itself impossible to isolate. More than twenty years after the first publications there is still no independent replication.
What it is used for
Dosing
- The animal studies used microgram-range doses in rats over short courses 13; these do not translate into a human dose and no allometric scaling has been validated for this compound.
- User protocols that circulate typically propose a few milligrams per day for 10-20 days. Those figures are an artefact of the vial size sold, not a research finding.
- There is no dose-finding study, no maximum tolerated dose, no human pharmacokinetics and no dose-response curve. 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 validatedSource: user protocols and vendor material
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.
| Days 1-10, some protocols to 20 | a few milligrams per day by subcutaneous or intramuscular injection |
|---|---|
| Repeat | once or twice a year |
No publication supports any milligram figure for Cortagen. The animal work used microgram doses in rats over short courses, and the circulating number follows the vial size. The Russian capsule product in the Cytomax and Cytogen lines is swallowed and is a different preparation from the injected powder this schedule describes.
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 capsules in the Russian bioregulator line, a different product
- 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 Cortagen
Safety
Side effects
- Not systematically documented, because no systematic safety research exists - the 15 indexed papers contain no safety or tolerability study 8. An empty side effect profile reflects absence of investigation, not demonstrated safety
- Reported at user level only, uncontrolled and unverifiable: injection site reactions, headache
Do not use if
- Pregnancy and breastfeeding - no data
- Children and adolescents - no data
- Hypersensitivity to the peptide or to benzyl alcohol in the diluent
- No toxicology, carcinogenicity or reproductive toxicity study appears anywhere in the indexed literature 8, so no evidence-based statement about who should avoid it is possible
Interactions
Not studied. No interaction data of any kind exist.
Sources
- Effect of tetrapeptide cortagen on regeneration of sciatic nerveBulletin of Experimental Biology and Medicine, 2000
- Tissue-specific effects of peptidesBulletin of Experimental Biology and Medicine, 2001
- The delayed effect of cortagen on the restoration of injured nerve functionDoklady Biological Sciences, 2002
- In vitro effect of short peptides on expression of interleukin-2 gene in splenocytesBulletin of Experimental Biology and Medicine, 2002
- Elucidation of the effect of brain cortex tetrapeptide Cortagen on gene expression in mouse heart by microarrayNeuroendocrinology Letters, 2004
- Synthesis of IL-2 mRNA in cells of rat hypothalamic structures after injection of short peptidesBulletin of Experimental Biology and Medicine, 2005
- Publication index of the original research group (primary source, not independent)Khavinson, St Petersburg Institute of Bioregulation and Gerontology
- PubMed search for 'cortagen' - the complete indexed literature, 15 recordsPubMed