What Semax is, and why its literature is hard to check
In short
Semax is a synthetic analogue of the 4-10 fragment of ACTH, without hormonal activity. Almost all of its literature is in Russian journals and in rat models; the only clinical trial located, in acute ischaemic stroke, was controlled but neither randomised nor blinded. It does not appear in the US medicines register.
Semax is a synthetic analogue of the 4-10 fragment of adrenocorticotropic hormone, modified at its end to resist degradation. The part retained is the one without hormonal activity: it does not stimulate the adrenal cortex.
Start with what matters most: the shape of its evidence
This page is structured the other way round from the rest of the catalogue, for a reason.
For semaglutide or tirzepatide, anyone can go to the journal, read the whole trial and check whether what is said here is true. For Semax, they cannot. Almost all of its literature is in Russian journals, much of it without an English abstract: in the international index its titles appear in square brackets, which is precisely the mark that the original is not in English and has not been translated.
That does not mean the work does not exist or is badly done. It means something more specific and more useful to know: it cannot be verified from outside with the same effort, and a buyer should factor that in.
What has been published
- The only clinical trial located. In 1997, Semax was studied in 30 patients in the acute phase of hemispheric ischaemic stroke, against a control group of 80 patients with strokes of analogous severity and location treated with conventional therapy. The authors describe some influence on the rate of recovery of damaged neurological functions [1].
The shape of that trial matters as much as its result: it is a controlled study, but neither randomised nor blinded. With a control group assembled separately and no masking, the effect of the compound and the differences between the groups cannot be separated. - Animal models. In rats, its effect has been studied on behavioural and neurochemical alterations following early-life exposure to a drug [2].
- Work from the school that developed it. Reviews of stable regulatory oligopeptides cover the compound and its applications [3], and a comparative study analysed anticoagulant effects across this group of peptides, Semax and Selank included [4].
Regulatory status, with the scope stated
A query to the US agency's public medicines register on 10 September 2026 returned no match for this active substance [5]. Nor does it hold an authorisation in the European Union.
That is what has been checked. It is not equivalent to saying it is not registered in any country in the world: it is a statement about those two registers and nothing more.
This page describes published literature. It is not medical information, it does not describe a therapeutic use, and it does not replace any healthcare professional.
What to look at when comparing suppliers
- HPLC purity for the specific batch and identity confirmation, with a certificate you can read before buying.
- Be wary of claims without a citation. This is the compound where they are most abundant, precisely because checking them is costly.
- Real net content of the vial, not the nominal figure.
References
- [1] Gusev E.I. et al. (1997). [Effectiveness of semax in acute period of hemispheric ischemic stroke (a clinical and electrophysiological study)]. Zh Nevrol Psikhiatr Im S S Korsakova. PMID 11517472 View source
- [2] Glazova N.Y. et al. (2021). Semax, synthetic ACTH(4-10) analogue, attenuates behavioural and neurochemical alterations following early-life fluvoxamine exposure in white rats. Neuropeptides. PMID 33418449 View source
- [3] Ashmarin I.P. et al. (2003). [Highly stable regulatory oligopeptides: experience and applications]. Patol Fiziol Eksp Ter. PMID 14682258 View source
- [4] Liapina L.A. et al. (2006). [Comparison of anticoagulant effects of regulatory proline-containing oligopeptides: glyprolines, semax and selank]. Izv Akad Nauk Ser Biol. PMID 16634437 View source
- [5] Food and Drug Administration (Estados Unidos), registro Drugs@FDA: sin coincidencias para «semax», consultado el 10-09-2026. View source
This page reports what has been published in the scientific literature about a research molecule. It is not medical information, it does not describe a therapeutic use, and it does not replace any healthcare professional. The product is sold strictly for in vitro research.
