Semax vs Pinealon
Semax is the synthetic heptapeptide Met-Glu-His-Phe-Pro-Gly-Pro, an ACTH(4-7) fragment extended with a C-terminal Pro-Gly-Pro tripeptide that resists enzymatic degradation, and it is registered in Russia for ischaemic stroke, optic nerve disease and cognitive indications. Pinealon is the tripeptide Glu-Asp-Arg, one of the ultrashort peptide bioregulators developed at the St Petersburg Institute of Bioregulation and Gerontology, proposed to act by entering the nucleus and binding DNA and histone proteins. The two are habitually paired because both are Russian-origin nootropic peptides sold for cognition. No published experiment has administered them together or set them against each other, in any species. What the literature contains instead is a set of publications that engage both compounds without comparing them, plus one 2025 mouse study that tested Semax against a derivative built by inserting the Glu-Asp-Arg sequence into the Semax backbone. Everything else is indirect: two separate evidence bases with different models, endpoints and standards of proof.
No study has compared them directly.
Everything below is drawn from separate studies that used different models, endpoints and species. That is a real limit on what can be concluded, not a formality.
No study has administered Semax and Pinealon to the same animals or the same participants, and none has compared them against each other in vitro. Searches of PubMed and Europe PMC returned eight publications that engage both compounds, and every one of them is a review, a classification exercise, or an experiment in which only one of the two was dosed. Most originate from the St Petersburg group that developed the ultrashort peptides, which repeatedly places Semax and the Glu-Asp-Arg peptide in the same category of short synthetic neuroprotectors and contrasts that category with the polypeptide complexes cortexin and Cerebrolysin. The closest approach to a direct test is a 2025 transgenic mouse study of Alzheimer's-type pathology in which Semax was compared with a derivative heptapeptide, Met-Glu-Asp-Arg-Pro-Gly-Pro, made by substituting His-Phe with Asp-Arg so that the molecule carries the Glu-Asp-Arg sequence internally. That experiment tested a hybrid molecule rather than Pinealon, and its authors did not present it as a comparison of the two marketed peptides.
The 8 publications that cover both
- 01Animal in vivo2025
The Potential of the Peptide Drug Semax and Its Derivative for Correcting Pathological Impairments in the Animal Model of Alzheimer's Disease
Radchenko AI, et al. · Acta Naturae · transgenic APPswe/PS1dE9/Blg mice; open field, novel object recognition and Barnes maze tests after a washout period, followed by histological examination of cortex and hippocampus
Semax was compared with a derivative heptapeptide, Met-Glu-Asp-Arg-Pro-Gly-Pro, produced by replacing His-Phe with Asp-Arg so that the molecule carries the Glu-Asp-Arg sequence marketed as Pinealon. Both peptides improved performance on the behavioural tests relative to untreated transgenic controls and reduced amyloid plaque counts in cortex and hippocampus, with plaque numbers 2.6-fold lower in the Semax group and 1.7-fold lower in the derivative group. The tripeptide itself was never given as a separate arm.
- 02Systematic review2021
Peptide Regulation of Gene Expression: A Systematic Review
Khavinson VK, et al. · Molecules · systematic review of peptide regulation of gene expression across plants, microorganisms, insects, birds, rodents, primates and humans
The review tabulated EDR under the trade name Pinealon among short peptides described as binding DNA and histone proteins and increasing the transcriptional availability of gene promoter zones, and separately described Semax and its C-terminal metabolite Pro-Gly-Pro as increasing nerve growth factor and brain-derived neurotrophic factor messenger RNA in rat brain regions. The two compounds were assigned to one regulatory framework, but no experiment using both was reported.
- 03In vitro2024
Short Peptides Protect Fibroblast-Derived Induced Neurons from Age-Related Changes
Kraskovskaya N, et al. · International Journal of Molecular Sciences · induced cortical neurons transdifferentiated from dermal fibroblasts of elderly human donors; EDR, KED and AEDG peptides
The experiment applied the Glu-Asp-Arg peptide sold as Pinealon together with two related tripeptides and did not administer Semax. The authors classified semax, cortagen and pinealon together as short synthetic peptides in contrast with the polypeptide complexes cortexin and Cerebrolysin, and set their own dendritogenesis results against published Semax findings on glutamatergic synaptic activity. EDR reduced oxidative DNA damage in the induced neurons, while none of the peptides altered mitochondrial or lysosomal activity or p16 levels.
- 04Animal in vivo2021
Neuroprotective Effects of Tripeptides-Epigenetic Regulators in Mouse Model of Alzheimer's Disease
Khavinson V, et al. · Pharmaceuticals (Basel) · 5xFAD transgenic mice with dendritic spine analysis, plus molecular docking of peptides to double-stranded DNA
The introduction placed Semax and the EDR peptide side by side, describing Semax as a fragment of adrenocorticotropin and the first short peptide drug reported to have neuroprotective properties, and EDR under the name Pinealon as a component of Cortexin with activity said to resemble that drug. Only KED and EDR were administered, and both prevented dendritic spine loss in the transgenic mice. A correction to this article was published in 2025.
- 05Review2022
Neuroepigenetic Mechanisms of Action of Ultrashort Peptides in Alzheimer's Disease
Ilina A, et al. · International Journal of Molecular Sciences · narrative review of ultrashort peptides in Alzheimer's disease
The review analysed EDR and the Semax sequence Met-Glu-His-Phe-Pro-Gly-Pro within a single set of ultrashort neuroprotective peptides, attributing to EDR a binding site in the promoter region of the SOD2 gene and to Semax stimulation of neuroglial, vascular endothelial and progenitor cell proliferation in the subventricular zone. The peptides were assigned overlapping roles in Alzheimer's disease mechanisms, without any comparative experiment.
- 06Review2024· Russian (English abstract)
[Prospects for use of short peptides in pharmacotherapeutic correction of Alzheimer's disease.]
Ilina AR, Popovich IG, Ryzhak GA, Khavinson VK · Advances in Gerontology (Uspekhi Gerontologii) · narrative review of short peptides in Alzheimer's disease therapy
Glu-Asp-Arg and Met-Glu-His-Phe-Pro-Gly-Pro were listed together among seven short peptides described as multitarget agents for Alzheimer's disease, alongside Leu-Ile, Glu-Trp, Lys-Glu, Gly-Pro and Lys-Glu-Asp. The authors argued for a combination strategy in contrast to the classical single-target approach, and presented no data separating the contributions of the individual peptides.
- 07Review2013· Russian (English abstract)
[Neuroprotective effects of peptides bioregulators in people of various age]
Umnov RS, Lin'kova NS, Khavinson VKh · Advances in Gerontology (Uspekhi Gerontologii) · review of peptide bioregulators in human populations of different ages
The review set out comparative characteristics of two groups of neuroprotective peptides: polypeptide complexes such as cortexin and cerebrolysin, and short peptides including semax, kortagen and pinealon. It described clinical application in elderly and old people and the cellular and molecular mechanisms attributed to each group. This is the closest the literature comes to a side-by-side treatment of the two compounds, and it is a narrative synthesis from the originating research group rather than an experiment.
- 08Review2026
Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions
Rahman OF, Lee SJ, Seeds WA · Journal of the American Academy of Orthopaedic Surgeons Global Research & Reviews · narrative review of therapeutic peptides in orthopaedic recovery
Pinealon was tabulated among sleep and recovery peptides said to act on mitochondrial antioxidants and neuronal support, while Semax was tabulated among neuroactive peptides said to act through brain-derived neurotrophic factor, TrkB and anti-inflammatory genes. The two therefore appeared in different functional groups within the same review. The authors stated that preclinical studies are promising but that there is a current lack of clinical trials, and neither compound was administered.
Side by side.
| Semax | Pinealon | |
|---|---|---|
| Evidence maturity | Approved drug | Preclinical only |
| Studies cited here | 18 | 18 |
| Published 2023 or later | 10 | 3 |
| Newest paper | 2025 | 2024 |
| Sequence and origin | A synthetic heptapeptide, Met-Glu-His-Phe-Pro-Gly-Pro, corresponding to the ACTH(4-7) fragment with a C-terminal Pro-Gly-Pro extension that confers resistance to enzymatic degradation. It lacks corticotropic activity and was developed at the Institute of Molecular Genetics in Moscow. | A synthetic tripeptide, Glu-Asp-Arg, developed at the St Petersburg Institute of Bioregulation and Gerontology as one of a family of ultrashort peptide bioregulators. The trade name derives from the organotypic pineal cell culture used in early work on the peptide. |
| Mechanism as described in the literature | Regulation of nerve growth factor and brain-derived neurotrophic factor expression, broad transcriptomic modulation of inflammatory and neurosignalling genes in rodent cerebral ischaemia, and copper chelation that strips Cu(II) from amyloid beta and silences its redox activity. | An epigenetic mechanism: the peptide is described as entering the nucleus, binding specific DNA sequences and histone proteins, and thereby altering expression of apoptosis, antioxidant and neuroplasticity genes. The supporting evidence is molecular docking and in vitro binding rather than in vivo target engagement. |
| Size and composition of the evidence base | Eighteen studies in this library: eight animal in vivo, six human clinical and four in vitro. The animal work is concentrated in rodent middle cerebral artery occlusion transcriptomics from a single Moscow group, with two primary studies from outside Russia. | Eighteen studies in this library: nine in vitro, four animal in vivo, four reviews and one human clinical report. Essentially the entire corpus, reviews included, originates from one St Petersburg research group, and independent replication is effectively absent. |
| Best-characterised finding | Region- and time-dependent induction of NGF and BDNF gene expression in rat hippocampus, frontal cortex and retina, and partial normalisation of ischaemia-disrupted gene expression profiles in the rat brain after experimental stroke. | Restriction of reactive oxygen species accumulation and reduced necrotic cell death in cerebellar granule cells, neutrophils and PC12 cells under oxidative stress, together with physical evidence that the peptide penetrates the major groove of DNA and contacts guanine N7 and O6 atoms. |
| Human data | Present but not regulatory-grade. Russian trials in acute and rehabilitative ischaemic stroke, optic nerve disease and motor neuron disease were open-label or actively controlled rather than double-blind and placebo-controlled. Two small placebo-controlled resting-state fMRI studies in healthy volunteers reported acute changes in functional connectivity and in the default mode network. | Almost absent. No randomised, placebo-controlled trial of the peptide alone has been published. The one occupational study located tested combined peptide bioregulators in lorry drivers with no placebo arm and no Pinealon-only group, and other human claims appear only inside narrative reviews from the originating group. |
| Evidence maturity and regulatory status | Classified as an approved drug: it holds a Russian marketing authorisation for ischaemic stroke and optic nerve indications. No Semax trial has been registered or completed under EMA or FDA standards, and no approval exists outside Russia. | Classified as preclinical only. It is supplied as a peptide bioregulator rather than a registered medicine, and no medicines regulator has assessed it for any indication. |
| Recency of primary research | Active. Ten of the eighteen entries date from 2023 or later, including 2025 work on transgenic Alzheimer's models, spinal cord injury in mice, calcium dynamics in rat brain slices and copper-amyloid redox chemistry. | Slowing. The newest primary study dates from 2024 and only three of eighteen entries are from 2023 onward; recent records are largely reviews and computational modelling rather than new experiments on the peptide itself. |
| Basis of most marketing claims | Extrapolation from Russian stroke and optic nerve trials, and from rodent neurotrophin and transcriptomic work, to cognitive enhancement in healthy adults, an application supported only by two small imaging studies with surrogate endpoints. | Extrapolation from cell-culture antioxidant data and from the wider ultrashort peptide class to memory and cognition in humans, with no pharmacokinetic data and no demonstration that the administered tripeptide reaches brain tissue intact. |
And what it does not.
Nothing in the published record establishes how these two peptides compare, because no experiment has run them side by side. The asymmetry between them is nonetheless large. Semax carries a Russian marketing authorisation, an active and partly non-Russian primary literature, and human studies in stroke and optic nerve disease, although none of those studies met the double-blind placebo-controlled standard Western regulators apply, and the claims made for cognition in healthy adults rest on two small imaging experiments with surrogate endpoints. Pinealon has no trial of the peptide alone in humans, no pharmacokinetic data, and an evidence base that begins and ends with one research group; its central epigenetic mechanism is supported by docking and binding studies rather than demonstrated target engagement in a living brain. The one experiment that comes close to a comparison tested Semax against a hybrid molecule carrying the Glu-Asp-Arg sequence, not against Pinealon, and both arms behaved similarly in mice. A reader looking for published grounds to prefer one over the other will not find them.
Common questions.
- Has any experiment given Semax and Pinealon to the same animals?
No. Searches of PubMed and Europe PMC located no study in which both compounds were administered, in any species or any model. The publications that engage both are reviews and classification papers, together with experiments in which only one of the pair was dosed. The nearest case is a 2025 transgenic mouse study of Alzheimer's-type pathology that compared Semax with a derivative heptapeptide carrying the Glu-Asp-Arg sequence internally, and that derivative is a different molecule from the tripeptide sold as Pinealon.
- What did the 2025 mouse study of the Semax derivative show?
Transgenic APPswe/PS1dE9/Blg mice were assessed in open field, novel object recognition and Barnes maze tests and then examined histologically. Both Semax and the derivative heptapeptide improved cognitive performance relative to untreated transgenic animals and reduced amyloid plaque counts in cortex and hippocampus, the reduction being 2.6-fold for Semax and 1.7-fold for the derivative. The effect persisted after a washout period. No arm received the Glu-Asp-Arg tripeptide by itself, so the study does not measure Pinealon.
- Why do so many papers name both peptides without comparing them?
Both belong to the Russian short-peptide research tradition, and reviews from the St Petersburg group routinely sort neuroprotective agents into polypeptide complexes such as cortexin and cerebrolysin on one side and short synthetic peptides such as semax, cortagen and pinealon on the other. That classification puts the two names in one table without generating any data on their relative activity. A 2026 orthopaedic review went in the opposite direction and assigned them to different functional groups, sleep and recovery for one and neuroactive for the other.
- Which of the two has been studied outside its country of origin?
Semax has, though only to a limited extent. Its evidence base includes a 2025 mouse spinal cord injury study conducted outside Russia and Italian work on copper-amyloid interactions in cell-free and membrane models. Pinealon has no comparable independent record: the in vitro, rodent and review literature traces back to one St Petersburg institute, and the computational transport modelling comes from the same authors. Independent replication is a meaningful difference between the two, because it is what converts a single group's findings into an established result.
- Does either compound have evidence for cognition in healthy adults?
Neither has strong evidence. For Semax there are two small placebo-controlled resting-state fMRI studies in healthy volunteers, which reported changes in amygdala connectivity and in the volume of the rostral subcomponent of the default mode network. Those are imaging surrogates rather than cognitive outcomes. For Pinealon there is no randomised placebo-controlled trial at all; the human claims appear inside narrative reviews and in an uncontrolled occupational study that used combined peptide bioregulators rather than the tripeptide alone.
For research purposes only. Not for human consumption, diagnosis, treatment, or prevention of any condition. Nothing on this page is medical advice, and no comparison here should be read as a recommendation of either compound.