Selank vs Pinealon
Selank is a synthetic heptapeptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, built from the immunomodulatory tetrapeptide tuftsin with a stabilising Pro-Gly-Pro extension and developed at the Institute of Molecular Genetics in Moscow as an anxiolytic. Pinealon is the synthetic tripeptide Glu-Asp-Arg, one of the ultrashort peptide bioregulators developed at the St Petersburg Institute of Bioregulation and Gerontology, and its originators describe it as an epigenetic regulator that enters the nucleus and binds DNA and histone proteins rather than as a receptor ligand. Both are Russian in origin, both are supplied outside Russia as cognitive or mood-oriented research compounds, and that shared framing is why they are set side by side. No published study has administered both. The only indexed publication that names them together is a 2026 orthopaedic review that ran no experiment, so the comparison below is indirect and the two evidence bases differ in kind as much as in size.
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 published experiment has given Selank and Pinealon within the same design, in humans, animals or cell culture. Searches of PubMed and Europe PMC using trade names, the full Thr-Lys-Pro-Arg-Pro-Gly-Pro and Glu-Asp-Arg sequences and the EDR abbreviation returned a single record engaging both, and it administered nothing. Rahman and colleagues reviewed therapeutic peptides in orthopaedics in 2026 and placed Pinealon among sleep and recovery agents while placing Selank among neuroactive peptides described as acting on brain-derived neurotrophic factor pathways. The two appeared in different sections of that review, were never compared, and the authors closed by noting a current lack of clinical trials for the whole class. Everything that follows is therefore assembled from separate studies conducted by different groups, in different models, with endpoints that were never chosen to be comparable: anxiety rating scales and enkephalin enzymology on one side, cell viability and peptide-DNA binding assays on the other.
The publication that covers both
- 01Review2026
Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions
Rahman OF, et al. · JAAOS Global Research & Reviews · narrative review of therapeutic peptide classes proposed as adjuncts in orthopaedic injury management
The review described Pinealon as a tripeptide thought to influence neuronal metabolism and mitochondrial function in ageing or stressed neural tissue, and listed it in a table of sleep and recovery agents. Selank was covered separately, among neuroactive peptides said to enhance brain-derived neurotrophic factor signalling. No experiment was conducted, the two peptides were not compared with each other, and the authors stated that clinical trials for this class of compounds are lacking.
Side by side.
| Selank | Pinealon | |
|---|---|---|
| Evidence maturity | Early clinical | Preclinical only |
| Studies cited here | 15 | 18 |
| Published 2023 or later | 0 | 3 |
| Newest paper | 2022 | 2024 |
| Sequence and origin | A seven-residue peptide, Thr-Lys-Pro-Arg-Pro-Gly-Pro, derived from the endogenous immunomodulatory tetrapeptide tuftsin with a Pro-Gly-Pro extension added to resist enzymatic degradation. It was developed at the Institute of Molecular Genetics in Moscow. | A three-residue peptide, Glu-Asp-Arg, one of a designed family of ultrashort bioregulators from the St Petersburg Institute of Bioregulation and Gerontology. It is not presented as a fragment or analogue of an endogenous human peptide. |
| Mechanism as described in the literature | Inhibition of enkephalin-degrading enzymes in plasma, allosteric interaction with the GABAergic system inferred from gene-expression panels, and regulation of BDNF and inflammation-related genes. No specific receptor has been identified. | Nuclear entry and sequence-specific interaction with DNA and histone proteins, supported by fluorescence binding assays, spectroscopy and molecular dynamics. The originating reviews state this epigenetic mechanism as a hypothesis rather than a demonstrated pathway. |
| Size of the evidence base | Fifteen verified publications in the research entry here: five human clinical studies, five rodent in vivo studies, three in vitro studies and two reviews. | Eighteen verified publications: nine in vitro studies, four rodent in vivo studies, four reviews and one human clinical report. |
| Best-characterised finding | Dose-dependent inhibition of plasma enkephalin hydrolysis, reported as more potent than bacitracin or puromycin, together with reproducible changes across a panel of GABAergic and neurotransmission-related genes in rat frontal cortex. | Restriction of reactive oxygen species accumulation and reduced necrotic cell death in cerebellar granule cells, neutrophils and PC12 cells under oxidative stress, and partial penetration of the DNA major groove with contacts at guanine N7 and O6 atoms. |
| Human data | Five studies, all Russian: comparative trials against medazepam and phenazepam in generalised anxiety disorder, neurasthenia and somatoform disorders, an immunological study in anxiety-asthenic disorders, and a placebo-controlled resting-state fMRI study in healthy volunteers. None was a placebo-controlled efficacy trial conducted outside Russia. | One study, an occupational trial in lorry drivers in which the tripeptide was applied in combination with a second bioregulator, without a placebo arm and without an arm testing the tripeptide alone. |
| Evidence maturity | Early clinical. Controlled human trials exist but used active comparators rather than placebo, were conducted in one country, and were not followed by a phase III programme. | Preclinical only. The human report does not isolate the compound, and no controlled trial of the tripeptide alone has been published. |
| Recency of primary research | Dormant. No primary Selank research article has been indexed in PubMed since 2022, and no publication in the entry is dated 2023 or later. | Slow but ongoing. Three publications are dated 2023 or later, the most recent a 2024 in vitro study of induced neurons derived from elderly human donor fibroblasts, and a 2023 computational study of transporter binding. |
| Basis of most marketing claims | Extrapolation from Russian comparative trials in diagnosed anxiety disorders to cognitive and mood claims in healthy adults, a population in which only two small imaging studies exist. | Extrapolation from cell culture, molecular docking and the wider ultrashort peptide class to cognitive outcomes, with no controlled human trial of the compound alone to anchor them. |
And what it does not.
The published literature offers no basis for preferring one of these peptides over the other, because they have never been examined together. What the separate records support is asymmetric. Selank has reached patients: randomised and comparative Russian trials in generalised anxiety disorder, neurasthenia and somatoform disorders reported anxiolytic effects broadly similar to benzodiazepine comparators, and one placebo-controlled imaging study in healthy volunteers detected changes in amygdala connectivity. Those trials used active comparators rather than placebo, came from a small group of laboratories in one country, and have not been replicated elsewhere; primary Selank research stopped appearing in PubMed after 2022. Pinealon has not reached that stage at all. Its evidence is dominated by in vitro binding, cell viability and docking work from a single institute, and its one human report tested a combination rather than the peptide alone. Neither compound has an established pharmacokinetic profile, an identified molecular target confirmed in vivo, or controlled evidence of a cognitive effect in healthy adults.
Common questions.
- Is there any experiment in which Selank and Pinealon were tested side by side?
There is not. Searches of PubMed and Europe PMC across trade names, sequences and the EDR abbreviation located one publication naming both, a 2026 narrative review of therapeutic peptides in orthopaedics, which discussed them in separate sections and conducted no experiment. The whole Pinealon corpus indexed in Europe PMC contains fewer than thirty records, and that review is the only one of them that mentions Selank at all. Any claim about relative potency or relative benefit is therefore an inference rather than a measurement.
- Which of the two has been tested in patients rather than in cells?
Selank. Its research entry contains five human studies, including comparative trials against medazepam and phenazepam in patients with generalised anxiety disorder, neurasthenia and phobic or somatoform disorders, and a placebo-controlled resting-state fMRI study in healthy volunteers. Pinealon has one human report, an occupational study in lorry drivers where it was applied together with a second peptide and without a placebo group, so no human result attributable to the tripeptide alone exists in the indexed literature.
- Do the two peptides act on the same biological system?
The published mechanisms do not overlap. Selank has been studied as an inhibitor of enkephalin-degrading enzymes and as a modulator of GABAergic and BDNF-related gene expression, with effects measured in plasma enzymology, hippocampal electrophysiology and rat cortical gene panels. Pinealon is described as entering the cell nucleus and binding DNA and histone proteins, with supporting evidence from spectroscopy, molecular dynamics and fluorescence assays. No study has tested whether the two converge on any shared downstream pathway.
- Why has Selank research stopped appearing?
The indexed record simply ends: no primary Selank research article has been published in PubMed since 2022, and no phase III programme has been registered. The compound was developed and trialled almost entirely within a small group of Russian laboratories, and no independent Western group has taken up the work. That leaves the existing trials without external replication, and it means the newest human data on the compound is now several years old and was generated under study designs that used active comparators rather than placebo.
- Has either peptide been shown to reach the brain intact?
Neither has been demonstrated directly. Selank has been given intranasally in rodent and human studies and produced measurable central changes, including altered hippocampal BDNF expression in rats and altered resting-state connectivity in humans, but the proportion of a dose reaching central targets has not been quantified. For Pinealon the transport question has been approached computationally, through docking of ultrashort peptides against LAT and PEPT family transporters, and the predicted transport has not been confirmed experimentally.
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.