What Semax is
Semax is a synthetic heptapeptide, Met-Glu-His-Phe-Pro-Gly-Pro. The first four residues are the ACTH(4-7) fragment of adrenocorticotropic hormone; the C-terminal Pro-Gly-Pro tail was added to slow enzymatic breakdown. It was developed in the 1980s at the Institute of Molecular Genetics in Moscow, and it is often described in the literature as an ACTH(4-10) analogue.
Short ACTH fragments of this kind do not carry the adrenal-stimulating (corticotropic) activity of the full hormone, which is why they have been studied for their effects on the nervous system instead.
What researchers study
Most published Semax research comes from Russian groups and uses rodent models. Recurring topics are neurotrophin signalling, especially BDNF and its receptor TrkB in the hippocampus (Dolotov et al., 2006); dopaminergic and serotonergic activity (Eremin et al., 2005); behaviour after early-life drug exposure (Glazova et al., 2021); and experimental cerebral ischemia. Its mechanism is not fully settled; some work points to melanocortin receptor interactions.
Regulatory status (October 2026)
Semax is a registered medicine in Russia, mainly as intranasal drops, and has been on the Russian List of Vital and Essential Drugs since 2011. It is not approved by the FDA. On July 24, 2026, FDA’s Pharmacy Compounding Advisory Committee voted 8–5 (one abstention) to recommend adding Semax to the Section 503A bulks list, after reviewing it for cerebral ischemia, migraine and trigeminal neuralgia. The recommendation is not binding and rulemaking is pending.
Semax vs. Selank
Semax and Selank are both Russian-developed regulatory peptides with Pro-Gly-Pro-type stabilizing tails, and they are often discussed together. They come from different parent molecules: Semax from ACTH, Selank from tuftsin, an immunomodulatory tetrapeptide.
Common questions
Is Semax approved in the US?
No. It is a registered medicine in Russia but not FDA-approved. An FDA advisory committee recommended it for the 503A compounding bulks list in July 2026; the recommendation is not binding.
What is Semax made from?
It is a synthetic seven-amino-acid peptide: the ACTH(4-7) fragment followed by a Pro-Gly-Pro tail.
How is Semax different from Selank?
Both are Russian-developed peptides, but Semax is based on ACTH while Selank is based on tuftsin.
Background sources
Chemistry & identity
| CAS Number | 80714-61-0 |
|---|---|
| Molecular Formula | C37H51N9O10S |
| Molecular Weight | 813.9 g/mol |
| Residue Count | 7 |
| PubChem CID | 9811102 |
Peptide sequence
MEHFPGP
Selected research references
Published peer-reviewed literature on Semax. Provided for research-context purposes only; Central Coast Peptides does not make claims about outcomes in humans.
- Semax, synthetic ACTH(4-10) analogue, attenuates behavioural and neurochemical alterations following early-life fluvoxamine exposure in white rats
- Semax, an ACTH(4-10) analogue with nootropic properties, activates dopaminergic and serotoninergic brain systems in rodents
- Semax, an analog of ACTH(4-10) with cognitive effects, regulates BDNF and trkB expression in the rat hippocampus
Related lab guides
- How to read a peptide certificate of analysis (COA) · HPLC purity, mass spec identity and net peptide content
- How to store lyophilized peptides · Temperature, moisture and light
- Reconstitution calculator · Concentration and mg per 0.1 mL for any vial size
Semax for laboratory research
Central Coast Peptides supplies Semax as a lyophilized reference material with a third-party COA. Ships from California.
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