Cortexin vs Davunetide

Polypeptide bioregulator from bovine cortex; modulates neurotransmitter activity; activates GABA and dopamine systems; reduces excitotoxicity; stimulates neuronal repair

Cortexin is a polypeptide bioregulator derived from porcine cerebral cortex, used clinically in Russia and Eastern Europe as a neuroprotective and nootropic agent for stroke, traumatic brain injury, and chronic cerebrovascular disorders. It contains a complex mixture of tissue-specific neuropeptides, amino acids, and microelements proposed to support neuronal survival, reduce excitotoxic damage, and promote neurotrophic factor expression in injured brain tissue. Russian clinical trials have examined cortexin in acute ischemic stroke rehabilitation and other neurological conditions, with results suggesting potential benefit in functional recovery, though studies are predominantly published in Russian-language journals with limited methodological transparency by international standards. Cortexin is not FDA-approved; it is a licensed prescription drug in Russia and several post-Soviet states, where it has regulatory approval for neurological indications. Cortexin administration: in clinical settings where it is approved, cortexin is administered by intramuscular injection, typically as a 10 mg dose reconstituted in saline or procaine. Clinical courses in Russian practice involve daily injections over 10-day cycles, repeated 1–2 times per year for chronic neurological conditions. This administration pattern is common to several Russian polypeptide bioregulators, including cerebrolysin — another porcine-derived peptide mixture with a broader international clinical trial dataset — and cortagen, a cardiac-focus bioregulator from the same pharmacological class. Cortexin is the cerebral-cortex-specific member of this class; cortagen targets cardiovascular tissue, and thymalin targets thymic/immune tissue. Provider availability for cortexin outside Russia is limited compared to peptides with international regulatory approvals; it is occasionally carried by compounding pharmacies and specialized nootropic suppliers. The PeptideBase cognitive peptides directory lists verified providers who carry neuroprotective peptide compounds.

Stabilizes microtubules by interacting with tubulin and microtubule-associated proteins. Activates SIRT1, reduces amyloid-β toxicity, and enhances synaptic plasticity. Protects against tau hyperphosphorylation.

Davunetide (AL-108; NAP; NAPVSIPQ) is a synthetic octapeptide derived from activity-dependent neuroprotective protein (ADNP), initially identified as a neuroprotective sequence from ADNP and investigated in clinical trials as a candidate treatment for cognitive impairment associated with schizophrenia and tauopathies including progressive supranuclear palsy. Davunetide is proposed to stabilize microtubule dynamics by interacting with tubulin and preventing tau hyperphosphorylation-related cytoskeletal disruption, and preclinical models demonstrated neuroprotective and procognitive effects at nanomolar concentrations. Clinical investigation included Phase 2 trials examining cognitive outcomes and MRS neuroimaging biomarkers in schizophrenia patients, and a Phase 2/3 trial in progressive supranuclear palsy; results showed some neurochemical effects but no consistent meaningful cognitive improvement across clinical endpoints, and the PSP program did not meet its primary outcomes. Davunetide has no FDA approval and no approved indication in any jurisdiction; clinical development has been discontinued following negative trial outcomes, and while its preclinical neuroprotective profile remains scientifically interesting, the clinical evidence does not establish efficacy for cognitive enhancement or neuroprotection in any condition.