Selank – Learning Health

What it is

Selank is a seven-residue peptide built the same way as Semax, by the same institute. The first four residues are tuftsin — Thr-Lys-Pro-Arg — a naturally occurring fragment of immunoglobulin G heavy chain with immune-stimulating activity. The same stabilising Pro-Gly-Pro tail is appended to resist peptidase degradation.

Its development came out of the observation that tuftsin had behavioural as well as immune effects. It was designed and produced at the Institute of Molecular Genetics of the Russian Academy of Sciences in collaboration with the Zakusov Research Institute of Pharmacology, and is registered in Russia as an anxiolytic, typically administered as a nasal spray.

What it does in the body

The proposed mechanism is allosteric modulation of the GABA system — the same broad target as benzodiazepines, approached differently. Clinical observations that Selank’s effect profile resembles that of classical benzodiazepines prompted direct tests of the hypothesis: administering Selank or GABA to rats and measuring the expression of 84 genes involved in neurotransmission in frontal cortex found significant changes in 45 genes at one hour and 22 at three hours, with a positive correlation between the changes produced by Selank and by GABA. A follow-up in human IMR-32 neuroblastoma cells examined Selank, GABA and olanzapine effects on GABAergic genes.

A second strand concerns enkephalins. Selank has been reported to inhibit enzymes that degrade enkephalins, which would raise endogenous opioid-peptide tone — a plausible anxiolytic route independent of GABA. In rats, Selank attenuated aversive signs of morphine withdrawal.

And because it is built on tuftsin, immune effects are not incidental: a study in patients with anxiety-asthenic disorders found shifts in the Th1/Th2 cytokine balance over 14 days of treatment, and complete suppression of peripheral blood IL-6 gene expression in cells from patients with depression at one concentration in vitro.

What the human evidence shows

One substantive clinical study, and it is a comparative rather than placebo-controlled design.

Generalised anxiety disorder and neurasthenia, 2008. Sixty-two patients were studied: 30 received Selank and 32 received medazepam, a benzodiazepine. Assessment used the Hamilton, Zung and CGI scales, with serum enkephalin activity measured alongside. The reported result: the anxiolytic effects of both drugs were similar, but Selank also had antiasthenic and psychostimulant effects — that is, it reduced anxiety without the sedation a benzodiazepine causes, which if true is clinically meaningful. Patients had reduced leu-enkephalin half-life at baseline, correlating with disease duration and symptom severity, and this rose during Selank treatment.

A 2014 comparison against phenazepam, another benzodiazepine, has also been published by Russian authors. An immunological study in patients with anxiety-asthenic disorders reported the cytokine findings above.

There is no placebo-controlled trial, no Western trial, and no trial large enough to characterise either efficacy or safety to regulatory standards.

An unusually blunt Western assessment

A 2021 review in the Journal of Clinical Pharmacology grouped Selank with phenibut and described both as poorly studied Russian drugs with GABAergic mechanisms that are “inexplicably sold to US consumers as dietary supplements”. The review’s general argument is that compounds acting on GABA-A receptors warrant evaluation for abuse potential before public access — and it noted that poison-control calls about phenibut had risen substantially over five years. Selank has not shown that pattern; the review’s point is that nobody looked first.

Claims and what backs them

Claim as usually stated	Verdict	What the published evidence actually shows
Reduces anxiety	Mixed	One 62-patient study found anxiolytic effects comparable to a benzodiazepine. Registered for this indication in Russia. No placebo-controlled trial exists.
Anxiolytic without sedation	Unproven	The distinctive claim, from the 2008 comparative study, which reported additional antiasthenic and psychostimulant effects. Plausible and untested against placebo.
Acts on the GABA system	Partly supported	Supported by gene-expression work in rat frontal cortex showing changes correlated with GABA’s, and by human cell studies. Allosteric modulation is inferred, not directly demonstrated at the receptor.
Raises enkephalin levels	Mixed	Reported in the clinical study alongside symptom improvement, and consistent with the proposed enzyme-inhibition mechanism. Single-source.
Modulates immune function	Mixed	Th1/Th2 cytokine shifts reported in patients and IL-6 suppression in cells from patients with depression. Consistent with a tuftsin derivative; clinical significance unknown.
Non-addictive and safe long-term	Unproven	No dependence or withdrawal studies in humans. A Western pharmacology review specifically flagged the absence of abuse-potential evaluation for GABAergic agents sold to consumers.

Risks and unknowns

GABAergic agents deserve the abuse-potential question. Every well-characterised drug class acting at GABA-A receptors — barbiturates, benzodiazepines, phenibut — carries dependence and withdrawal liability. Selank’s modulation appears gentler and no dependence signal has been reported, but the studies that would detect one have not been done. Reasoning that it must be safe because no harm has been reported inverts the burden of proof.

Sold as a supplement, which it is not. The 2021 review’s objection is a regulatory one: a peptide drug registered in another country for a psychiatric indication is being sold to US consumers under a framework meant for vitamins and botanicals.

Confirmed grey-market circulation. Selank was one of the two peptides identified by mass spectrometry in suspicious preparations seized in Europe in 2017 and 2018, available online as injectable powder or nasal spray.

No independent replication. As with Semax, the clinical evidence comes from the institutional tradition that developed the compound.

Where regulators stand

RussiaRegistered as an anxiolytic medicine, used for generalised anxiety disorder and related conditions.

United StatesNot approved for any use. “Selank acetate (TP-7)” appears in the FDA’s table of bulk drug substances previously in Category 2 whose nominations were withdrawn by the nominators. It was not among the seven peptides reviewed at the July 2026 advisory committee meeting.

European UnionNo marketing authorisation. Seized preparations containing Selank have been analysed by official medicines control laboratories as illegal products.

SportNot named on the WADA 2026 Prohibited List. As a substance lacking approval for human therapeutic use in most jurisdictions, use would engage the S0 catch-all.

The bottom line

Selank is a thoughtfully designed peptide with a genuinely interesting claim attached to it: anxiety relief without the sedation and cognitive dulling that make benzodiazepines difficult to live with. If that were established it would matter.

It rests on one 62-patient comparative study from the institute that created the compound, with no placebo arm and no independent replication in nearly twenty years. Meanwhile it is sold in the United States as a dietary supplement — a framing that a Western pharmacology review called inexplicable, mainly because the abuse-potential work that any GABAergic drug should undergo has never been done.

References

Zozulia AA, Neznamov GG, Siuniakov TS, et al. Efficacy and possible mechanisms of action of a new peptide anxiolytic selank in the therapy of generalized anxiety disorders and neurasthenia. Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108(4):38–48 PMID 18454096 — in Russian; comparator was medazepam, not placebo
Volkova A, Shadrina M, Kolomin T, et al. Selank administration affects the expression of some genes involved in GABAergic neurotransmission. Front Pharmacol. 2016;7:31 PMID 26924987
Filatova E, Kasian A, Kolomin T, et al. GABA, Selank, and olanzapine affect the expression of genes involved in GABAergic neurotransmission in IMR-32 cells. Front Pharmacol. 2017;8:89 PMID 28293190
Uchakina ON, Uchakin PN, Miasoedov NF, et al. Immunomodulatory effects of selank in patients with anxiety-asthenic disorders. Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108(5):71–75 PMID 18577961 — in Russian
Doyno CR, White CM. Sedative-hypnotic agents that impact gamma-aminobutyric acid receptors: focus on flunitrazepam, gamma-hydroxybutyric acid, phenibut, and selank. J Clin Pharmacol. 2021;61(Suppl 2):S114–S128 PMID 34396551
Konstantinopolsky MA, Chernyakova IV, Kolik LG. Selank, a peptide analog of tuftsin, attenuates aversive signs of morphine withdrawal in rats. Bull Exp Biol Med. 2022;173(6):730–733 PMID 36322304
Vanhee C, Francotte A, Janvier S, Deconinck E. The occurrence of putative cognitive enhancing research peptides in seized pharmaceutical preparations. Drug Test Anal. 2020;12(3):371–381 PMID 31667971