What came out of this research program was not a weapon. It was a synthetic heptapeptide, seven amino acids arranged in a specific sequence, that Russian health authorities would, years later, approve for clinical use in neurological conditions such as ischemic stroke and encephalopathy. Its name is Semax.
In Russia and Ukraine, Semax has been on pharmacy shelves for decades. In the West, it is almost unknown. This asymmetry is, in itself, a fascinating scientific story, and it has everything to do with how scientific knowledge circulates (or does not) across political and linguistic borders.
In Russia, Semax has been approved for use in stroke. In the West, we have barely begun to ask the right questions about it.
The logic behind the molecule: deriving the best of ACTH
To understand Semax, one must understand where it came from. The starting point was ACTH, the adrenocorticotropic hormone produced by the pituitary. ACTH has multiple functions, but the Russian researchers were interested in one of them: the ACTH(4-10) fragment had demonstrated neurotrophic and cognitive properties in animal models, without the hormonal activity of full ACTH.
The scientific question was elegant: is it possible to isolate that specific function and create a more stable molecule, easier to work with? The answer was Semax, the ACTH(4-10) fragment with the addition of a C-terminal tripeptide (Pro-Gly-Pro) that increases its resistance to enzymatic degradation. The result: a molecule that does not stimulate the adrenal cortex, does not alter cortisol, but that studies indicate is capable of modulating the central nervous system.
The acronym that reveals the simplicity of the idea. The name Semax is a Russian acronym for “SEven AMino aCids.” An almost provocatively direct denomination for a molecule that science has investigated in contexts as complex as recovery after stroke and synaptic plasticity. The structural simplicity, ironically, may be part of what makes it interesting: few components, effects studied in multiple systems.
Approved in Moscow, unknown in New York: how the Iron Curtain affected science
Most of the clinical studies on Semax were published in Russian. This is not a detail, it is a structural barrier that limited the reach of this knowledge in the global scientific community. Research that does not appear in the large English-indexed databases tends to simply not exist for most Western researchers.
Semax was approved by Russian authorities for use in ischemic stroke, dyscirculatory encephalopathy, and optic neuropathy. Decades of clinical use accumulated a body of observations that, although published mostly in Russian and with methodological limitations by Western standards, represents something very few nootropic molecules have managed: real clinical history in real patients.
A clinical trial in 110 stroke patients (Polunin et al., 2018) reported that intranasal Semax elevated plasma BDNF levels in treated patients, and that patients with higher BDNF levels showed faster rehabilitation and better functional independence. A pilot study in 24 healthy volunteers (Lebedeva et al., 2018) identified measurable changes in the fMRI signal in regions associated with the default mode network.
These are preliminary data, small samples, methodology that does not fully meet FDA/EMA standards. But they are data. In a field where most nootropic compounds have not come close to a clinical study, that is notable.
Decades of approved clinical use in one country, almost no large study on the other side of the world. That is the story of Semax.
What modern science is finally beginning to explore
Western neuroscience began to look at Semax with more attention as interest in the BDNF/TrkB axis grew as a central line of research in the biology of aging and in neurodegenerative diseases. A molecule that potentially modulates this axis in a measurable way, and that already has decades of history in another regulatory context, cannot be ignored indefinitely.
In 2021, researchers published an analysis of protein expression in an ischemia-reperfusion model in rats (Filippenkov et al.) showing that Semax suppressed inflammatory processes and activated recovery pathways in subcortical regions. In 2025, a study on intracellular calcium dynamics in hippocampal neurons (Bobyntsev et al.) localized measurable effects of Semax specifically in the CA1 circuit, one of the most critical regions for memory formation.
These are not claims about what Semax does in humans. They are signals, in preclinical models, that justify continuing to ask the questions. And in this phase of the science, a molecule that continues generating interesting questions ten years after the first relevant studies has already demonstrated something important: that there is something there worth investigating.
Semax and Selank: the Soviet pair of the Neural & Cognitive System. Semax is not the only molecule of Russian origin in the Axion portfolio. Selank, a synthetic analog of tuftsin, also developed at the Russian Academy of Sciences, operates by distinct mechanisms, mainly via the serotonergic and GABAergic systems. Together, the two compounds represent a line of research in synthetic neuroactive peptides with a clinical history the West has not yet replicated.
What remains of this story
The story of Semax is the story of knowledge that has existed for decades, but that was produced in the wrong context to be widely adopted by the global scientific establishment. Published in Russian, validated by regulators that Western regulators do not recognize, accumulating clinical data that do not reach the large English-indexed journals.
What this does not mean: it does not mean Semax is effective for anything, nor that Russian approval equates to FDA approval. The existing clinical data have real limitations that need to be acknowledged.
What it does mean: there is a volume of research on this molecule, preclinical and clinical, that most compounds investigated as nootropics have never reached. And the relevant question is not “to trust or distrust Russian science.” The question is: when will the West replicate these studies with the methodological rigor they deserve?
