Semax

Semax is a synthetic seven-residue peptide Met-Glu-His-Phe-Pro-Gly-Pro, developed at the Institute of Molecular Genetics, Russian Academy of Sciences. Its sequence is the fragment 4-7 of adrenocorticotropic hormone (ACTH 4-7) — a region known since the 1970s to have nootropic and neurotrophic effects — extended with a C-terminal Pro-Gly-Pro tripeptide for protease resistance.

Semax is approved in Russia for cerebrovascular indications. CAS 80714-61-0, molecular formula C₃₇H₅₁N₉O₁₀S, molecular weight 813.93 g/mol. Wikidata QID Q4415058.

Semax modulates multiple CNS pathways. The most-cited effects include upregulation of BDNF expression in hippocampal and cortical tissue, modulation of melanocortin receptor signalling (ACTH-fragment derivation), and changes in neurotransmitter levels including serotonin and dopamine.

Delivered intranasally in most clinical and research protocols, achieving CNS exposure via the olfactory pathway.

Investigated in clinical and preclinical studies of ischaemic stroke recovery, cognitive function, attention deficits, and neuroprotection. As with Selank, the Russian clinical literature is substantial but less accessible to Western researchers than English-language sources.

Supplied as a research-grade reference standard for laboratory use only. Not a licensed medicinal product in the United Kingdom and not approved by the MHRA for human or veterinary administration. Sale is restricted to researchers, institutions and laboratory professionals; the compound must be retained within research premises. End-user compliance with the Human Medicines Regulations 2012, the Misuse of Drugs Act 1971 (where applicable) and local institutional biosafety policy is the responsibility of the buyer.