Semax and Selank are often mentioned together. Both are short synthetic peptides, both were developed at the Institute of Molecular Genetics of the Russian Academy of Sciences, and both share the same stabilizing “tail”. But they are built on different natural peptides and are studied for different reasons.
A shared design: the Pro-Gly-Pro tail
Short natural peptides are usually broken down within minutes. Both Semax and Selank end with the tripeptide Pro-Gly-Pro (PGP), which makes them more resistant to enzymes and lengthens their activity in research models. This shared design is the main reason they are grouped together.
Semax: an ACTH(4-10) analogue
Semax is a heptapeptide (Met-Glu-His-Phe-Pro-Gly-Pro). It is based on the 4–10 fragment of adrenocorticotropic hormone (ACTH), with the PGP tail added. Importantly, this fragment does not carry ACTH’s hormonal activity on the adrenal glands. Research on Semax has focused on:
- Expression of neurotrophic factors, particularly brain-derived neurotrophic factor (BDNF), in rodent brain tissue.
- Gene expression changes in models of neuronal stress.
- Melanocortin receptor interactions, given its ACTH origin.
Research compound: Semax (10mg)
Selank: a tuftsin analogue
Selank is also a heptapeptide (Thr-Lys-Pro-Arg-Pro-Gly-Pro). It is based on tuftsin, a natural tetrapeptide (Thr-Lys-Pro-Arg) that comes from immunoglobulin G and is involved in immune signalling, again with the PGP tail added. Research on Selank has examined:
- Behavioural models of anxiety-related responses in rodents.
- Interaction with the GABAergic system.
- Effects on enzymes that break down enkephalins, and on markers of immune signalling.
Research compound: Selank (10mg)
At a glance
| Semax | Selank | |
|---|---|---|
| Based on | ACTH(4-10) | Tuftsin |
| Sequence | Met-Glu-His-Phe-Pro-Gly-Pro | Thr-Lys-Pro-Arg-Pro-Gly-Pro |
| Main research focus | Neurotrophic factors (BDNF) | Anxiety-related models, GABA, immune signalling |
Semax was also among the peptides reviewed by an FDA advisory committee in July 2026. See Peptide Regulation in 2026. Independent Janoshik reports are on each product page.
All ReVICO Labs products are supplied for laboratory research use only. They are not for human or veterinary consumption and are not approved by Health Canada for therapeutic or diagnostic use.
