Cortexin is a prescription drug in Russia, not a designer research peptide. It is a lyophilized complex of water-soluble polypeptides extracted from the cerebral cortex of cattle and pigs, manufactured by Geropharm in St. Petersburg. The polypeptide fractions run roughly 500 to 15,000 daltons, so this is a tissue hydrolysate rather than a single defined molecule.
It is often filed under the "Khavinson bioregulators" umbrella because it comes out of the same St. Petersburg peptide-research tradition. Worth separating one thing: the famous Khavinson compounds like Cortagen or Epitalon are ultra-short synthetic peptides of two to four amino acids. Cortexin is different in kind. It is an animal-derived extract containing a mixture of neuropeptides, amino acids, and trace cofactors, not a synthesized sequence.
What it is used for
In Russia and several CIS countries, Cortexin is an approved pharmaceutical given by intramuscular injection. Its registered indications cover stroke, traumatic brain injury, encephalopathy, epilepsy, cognitive disorders, and developmental delay in children. None of that approval extends to the US, EU, UK, or other major Western regulators. The FDA and EMA have not evaluated or approved it.
Proposed mechanism
A 2018 review by N.V. Gulyaeva in the Korsakov Journal of Neurology and Psychiatry summarized the proposed neuroprotective pathways. The work describes effects spread across signal transduction, energy metabolism, proteolytic protein modification, cell structure, and neuroinflammation, rather than a single clean target. Three neuron-specific proteins were identified as molecular partners of cortexin peptides in brain tissue: β5-tubulin, creatine kinase B, and protein 14-3-3 α/β. In vitro work also showed that the preparation inhibited brain caspase-8, an enzyme in the apoptosis cascade, which fits the claimed anti-apoptotic framing. See the review on PubMed.
State of the evidence
This is the part buyers should read carefully. Cortexin has a large clinical track record inside Russia going back to the 1990s, including a study of combined therapy in stage I-II dyscirculatory encephalopathy in 76 patients (PubMed, 1999). More recently, a 2024 paper examined neurotropic effects in animal models of mental and physical developmental delay (PMC).
The most accessible controlled comparison is preclinical. A 2021 PLoS One study in rats put Cortexin head-to-head with Cerebrolysin and Actovegin in acute and chronic brain ischemia. Cortexin and Cerebrolysin came out comparable, both improving recovery of neurological function and reducing necrosis, while Actovegin underperformed (PMC).
What is largely missing is independent, Western, placebo-controlled human trial data published in high-profile international journals. Most of the human literature is Russian-language and originates close to the manufacturer. That does not make it worthless, but it means the evidence base outside its home market is thinner and harder to verify than the long usage history might suggest.
Quality and sourcing notes
Because Cortexin is a biological extract, identity and purity questions differ from those for synthetic peptides. The genuine pharmaceutical product is a specific Geropharm preparation. Material sold through research-chemical or grey-market channels as "cortexin" is not the regulated drug and may not match the documented composition. Anyone evaluating a vendor should expect a certificate of analysis and, for an animal-derived hydrolysate, treat broad purity claims with skepticism since a defined-percentage purity figure does not map cleanly onto a multi-fraction extract.
Nothing here is medical or dosing advice. Cortexin is not approved for human use in most countries, and where it is sold internationally it is generally handled as research-use-only material. WADA does not list it by name; that is not a clearance, and athletes should check current rules directly.