Peptide reference
Semax
Met-Glu-His-Phe-Pro-Gly-Pro ·ACTH(4-7)PGP ·Heptapeptide Semax
What cited sources report about Semax
Semax is a synthetic heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro) that was designed as an analog of ACTH(4-7) extended with a Pro-Gly-Pro stabilizing tail. The peptide is currently under review by the FDA Pharmacy Compounding Advisory Committee (PCAC), with a public meeting scheduled for July 24, 2026. As of the cited literature, Semax has no FDA-approved indication and no marketing authorization in the US, EU, UK, Canada, or Australia; cited Russian sources describe it as registered there as a nootropic nasal drug. The summaries below report what individual cited sources state; this page does not assert claims beyond what those sources report.
Kolbaev, Sharonova, and Skrebitsky (2025) — Bulletin of Experimental Biology and Medicine
A 2025 in-vitro electrophysiology study at the Research Center of Neurology in Moscow examined Semax application (1 µM) on rat hippocampal slices and cerebellar slices. The authors reported an increase in the frequency of spontaneous intracellular calcium fluctuations in CA1 pyramidal neurons but no significant change in proton-induced calcium responses in cerebellar granule cells, and they observed that the primary mechanism of Semax neuroprotection is unlikely to involve attenuation of calcium entry through acid-sensing ion channels in those granule cells.
Application of Semax (1 μM), significantly increased the frequency of spontaneous [Ca2+]i fluctuations in the pyramidal layer cells of the hippocampal CA1 field, but had no significant effect on proton-stimulated increase in [Ca2+]i in cerebellar granule cells.
Filippenkov et al. (2025) — International Journal of Molecular Sciences
Researchers at the Kurchatov Institute and Pirogov Russian National Research Medical University used RNA-Seq to profile differentially expressed genes in rat frontal cortex and striatum after transient middle cerebral artery occlusion (tMCAO), with and without administration of Semax (ACTH(4-7)PGP) or ACTH(6-9)PGP. The authors observed that the peptides reduced ischemia-induced disturbances in nearly two thousand genes related to neurotransmitter and inflammatory responses in the frontal cortex.
Previously, a significant effect of non-hormonal ACTH(4-7)PGP (Semax) and ACTH(6-9)PGP peptides on the functions of the nervous system was shown.
“Investigation of the effect of a modified fragment of neuropeptide Y” (2021) — Ceska a Slovenska Farmacie
A 2021 behavioural-pharmacology paper used Semax at 0.1 mg/kg as a reference comparator in passive-avoidance and extrapolation-escape paradigms while characterizing a modified neuropeptide-Y fragment (“NP9”). The authors documented that Semax is registered as a peptide nootropic medicine in the Russian Federation, providing a contemporaneous regulatory data-point on the peptide’s status outside the US.
The comparison drug used peptide nootropic medicine Semax® (Met-Glu-His-Phe-Pro-Gly-Pro) at a dose of 0.1 mg/kg.
PubChem CID 11765687 — National Center for Biotechnology Information
The PubChem compound record for Semax catalogues the heptapeptide sequence Met-Glu-His-Phe-Pro-Gly-Pro and aggregates synonym sets and links to underlying chemical and biological literature.
Coverage notes
Most of the published Semax literature has been authored by Russian groups (Kurchatov Institute, Research Center of Neurology, Lomonosov MSU) reflecting the peptide’s domestic regulatory pathway in Russia, where it is marketed as a nasal drug. There is no FDA-approved indication and no large, blinded clinical efficacy trial of Semax indexed on ClinicalTrials.gov as of the last_updated date. This page will be updated when the July 2026 PCAC briefing materials are released.