RESEARCH MONOGRAPH · KDC-MN-010

Selank

May 9, 2026 Kodiac biolabs Research Revised May 30, 2026 2 min read

Our opinion on this compound

72/100

Russian anxiolytic peptide with surprisingly clean evidence and a story that's barely known in the West

Selank is the synthetic analog of tuftsin (the natural tetrapeptide TKPR) with a Pro-Gly-Pro stabilizing tail bolted on for protease resistance, developed by the Semenikhin and Myasoedov groups at the Russian Academy of Sciences in the 1990s. The Russian and Ukrainian clinical literature on this is more substantial than most Western researchers realize, including multiple controlled trials in generalized anxiety disorder.

Mechanism is multi-pronged. Modulation of the GABAergic system (without direct GABA-A binding, so no benzo-like dependency profile), enkephalinase inhibition leading to elevated enkephalin tone, and BDNF upregulation in the hippocampus. The anti-anxiety effects appear to be mediated through a combination of these rather than a single dominant pathway, which is unusual for a small peptide and makes the pharmacology somewhat hard to model.

The clinical data from the Zozulya group at the Serbsky Center showed comparable anxiolytic efficacy to medazepam without sedation, cognitive blunting, or withdrawal effects on discontinuation. The trial designs aren't up to modern Western RCT standards but the effect sizes are consistent across studies and the safety profile across decades of clinical use in Russia is reassuring.

Intranasal administration is the studied route. Bioavailability via nasal mucosa is documented and reasonably efficient for a hydrophilic peptide, with rapid CNS penetration. Half-life is short but the downstream BDNF effects persist longer than the peptide itself does, which is why the dosing protocols in the Russian literature use repeated daily administration rather than chronic continuous exposure.

Sourcing is straightforward, seven residues, easy to synthesize and validate. Watch the proline content during synthesis (proline-rich peptides can have racemization issues at the alpha-carbon, but reputable vendors handle this fine). HPLC purity is achievable.

Whats holding back broader interest? Mostly the language barrier. The good papers are in Russian-language journals that haven't been systematically translated, and the few English papers come from the same research consortium. We'd love to see independent Western replication. The compound deserves it.

Solidly slept-on. Real biology, real clinical history, weak Western marketing.

Evidence: 60
Mechanism: 65
Reliability: 72
Safety: 82
Sourcing: 80
Value: 78
Signal: 72
Staying power: 68

Plain-language summary Intrigue 71 / 100

Selank is a synthetic seven-amino-acid peptide developed in Russia as an analog of the immune peptide tuftsin. It has anxiolytic and immunomodulating effects in research and is approved as a prescription anxiolytic in Russia. It does not produce sedation or dependence. Stocked in the Kodiac catalog as a research-only powder for laboratory work; not a medicine, not for human consumption.

Intrigue 0–100 blends mechanism novelty, evidence strength, and translational potential. Kodiac editorial, not peer-reviewed.

Synthetic heptapeptide anxiolytic, tuftsin analog

A 7-residue peptide developed at the Russian Academy of Sciences as a stable analog of tuftsin, characterized for anxiolytic, immunomodulatory, and cognitive endpoints in a substantial Russian-language literature.

Abstract

Selank (sequence Thr-Lys-Pro-Arg-Pro-Gly-Pro; CAS 129954-34-3; molecular formula C33H57N11O9; molecular weight 751.85) is a synthetic heptapeptide developed in the early 1990s at the Institute of Molecular Genetics of the Russian Academy of Sciences in collaboration with the Zakusov Research Institute of Pharmacology. The peptide is a stabilized analog of tuftsin, a naturally occurring tetrapeptide (Thr-Lys-Pro-Arg) derived from immunoglobulin G that has documented immunomodulatory effects but a very short half-life. Selank extends the tuftsin sequence with the C-terminal tripeptide Pro-Gly-Pro to confer protection against rapid peptidase degradation. The compound has been studied principally in the Russian clinical and preclinical literature, with the largest body of work on anxiolytic effects in generalized anxiety disorder, immunomodulatory effects in viral and bacterial infection models, and cognitive effects in attention and memory tasks. Selank is registered as a prescription medicine in the Russian Federation for the treatment of generalized anxiety disorder under the trade name Selank Bioregulator. The compound is not approved by any regulatory authority outside the Russian Federation; clinical use in the United States, the European Union, and Japan is off-label and outside the scope of regulatory oversight. The principal limitations on the strength of the evidence are the dominance of the Russian-language literature, limited Western independent replication of the most-cited findings, and the relatively small clinical sample sizes in the published trials.

Read the full monograph

The full reference document covers compound identification, discovery and developmental history, mechanism of action, pharmacokinetics, reported research dose ranges, sourcing and quality verification, reconstitution and handling, stack interaction considerations, and a curated reference list. Available as a research-use-only PDF download.

KDC-MN-010

The full reference document is provided strictly for research use only. It reports research dose ranges from the published literature, not instructions for use in humans or animals.

Download PDF →

Acquire Selank from the catalog

View Selank →

FOR RESEARCH USE ONLY. Not for medical, diagnostic, or therapeutic purposes. Not for human consumption. All information is provided for research and educational purposes only.

Kodiac sells research compounds for investigative use only.

Selank

Abstract

Read the full monograph

Quick actions

Categories

Help and policies

Abstract

Read the full monograph

Adjacent monographs