What it is
Selank is a lab-made chain of seven amino acids. The first four copy tuftsin, a tiny natural peptide cut from antibodies that signals immune cells. Three more amino acids (proline, glycine, proline) were added to the end so that the chain would not be broken down as quickly. Its developers studied it for effects on anxiety rather than on immunity.
In Russia it is registered as a medicine: nose drops for anxiety. It is not approved in the United States. Nearly all of the research comes from the Russian institute that created it and its partners, and most human studies are published in Russian.
Selank is H-Thr-Lys-Pro-Arg-Pro-Gly-Pro-OH (C33H57N11O9, 751.9 g/mol, CAS 129954-34-3). Residues 1–4 are tuftsin, the Thr-Lys-Pro-Arg fragment of the IgG heavy-chain Fc region; the C-terminal Pro-Gly-Pro glyproline was added to increase resistance to peptidases.
No single receptor has been identified. Mechanisms proposed by the developing group include inhibition of enkephalin-degrading enzymes in human serum, which would lengthen the half-life of endogenous enkephalins (Zozulya et al. 2001); concentration-dependent positive allosteric modulation of GABA binding in brain-membrane preparations (Vyunova et al. 2018); changes in expression of GABAergic-pathway genes in rat frontal cortex (Volkova et al. 2016); and changes in IL-6 and other inflammation-related transcripts.
Pharmacokinetic data come from the developer in rats. Tritium-labelled Selank appeared in blood within a minute of intranasal or intraperitoneal dosing; by 7 minutes blood levels had fallen by more than a third after intraperitoneal dosing and by half after intranasal dosing; brain levels after intranasal dosing tracked blood levels and declined more slowly. The in-vitro half-life is reported as about 2 minutes. No independent human pharmacokinetic study was found.
Who made it and when
Selank was designed at the Institute of Molecular Genetics of the Russian Academy of Sciences in Moscow, the same institute that produced Semax, working with the Zakusov Research Institute of Pharmacology. The idea traces back to Russian work in the early 1980s suggesting that tuftsin, an immune signal, might also act on the brain. The developers made the longer, more stable version and took it through Russian clinical trials. In 2009 Russia’s Ministry of Health registered “Selank 0.15%” nose drops as a medicine. It has never been approved in the United States.
Volkova et al. (2016) and Kolomin et al. (2013), both from the Institute of Molecular Genetics, describe Selank as designed and produced at that institute in cooperation with the V.V. Zakusov Research Institute of Pharmacology. Kolomin et al. trace the rationale to Valdman and Ashmarin’s early-1980s hypothesis that tuftsin, structurally similar to some neuropeptides, has central nervous system activity. The heptapeptide was selected from a series of C-terminally extended tuftsin analogues for anxiolytic activity in rodents.
According to the same developer review, “Selank 0.15%” nasal drops completed Russian preclinical and clinical testing and were registered and approved for medical use by the Russian Ministry of Health in 2009; the same review describes their use in generalised anxiety disorder and neurasthenia. FDA’s records use the name “selank acetate (TP-7)”. No US patent held by a pharmaceutical developer was verified for this article, so none is listed.
What the data say
In rats and mice, Selank has been tested in stress, anxiety, depression-like behaviour, learning and morphine-withdrawal models, and the reports describe calming effects without the sedation typical of benzodiazepine drugs. Almost all of this work is from the developer and its partners.
In people, the indexed evidence is thin. Two Russian studies compared Selank with benzodiazepine drugs in about 60 patients each, with anxiety disorders or neurasthenia. Both reported reduced anxiety with Selank, and one reported effects similar to its comparator drug. Neither had a placebo group, and the English summaries do not describe blinding. No trial of Selank is registered on ClinicalTrials.gov, and no independent group outside Russia has published a controlled human study.
Animal data: rodent studies from the developer network report anxiolytic-like effects in mouse stress models and a rat chronic mild stress model, improved conditioned-avoidance learning, potentiation of diazepam’s anxiolytic effect in rats (Kasian et al. 2017), antidepressant-like effects in WAG/Rij rats, and attenuation of aversive signs of morphine withdrawal. Rat doses cited in the developer’s 2013 review include 200 µg/kg intranasally and 1,000–2,000 µg/kg.
Human data: Zozulia et al. (2008, in Russian) compared Selank (n=30) with medazepam in 62 patients with generalised anxiety disorder or neurasthenia and reported similar anxiolytic effects, with additional “antiasthenic and psychostimulant” effects attributed to Selank, together with changes in the serum half-life of leu-enkephalin. Medvedev et al. (2014, in Russian) compared Selank with phenazepam in 60 patients with phobic-anxiety and somatoform disorders and reported a pronounced anxiolytic effect lasting about a week after the last dose. The English abstracts give no placebo arm, randomisation details or blinding, and doses are not stated in them. No registered trials, no pharmacokinetic study in humans and no systematic safety data in English were found. The evidence base is small, largely unblinded and almost entirely from the originating institutions.
Regulatory picture
Approval: no medicine containing Selank is approved by the FDA; its Russian registration does not apply in the United States. Compounding: in September 2023 the FDA put selank acetate in “Category 2”, the group of substances pharmacies should not compound from, citing possible immune reactions and impurities and a lack of human safety information. In September 2024 the FDA removed it from Category 2, explaining that the nominator had meant to nominate a different substance. That removal is not permission: Selank is not on the list of substances pharmacies may compound from, and it was not on the FDA advisory committee’s July 2026 agenda. Enforcement: FDA warning letters to two compounding businesses, in 2020 and 2021, named Selank among ingredients they should not have compounded.
Approval: none. No US IND-stage programme could be verified.
Compounding: “Selank acetate (TP-7)” was listed in 503A Category 2 in FDA’s update of 2023-09-29. FDA’s 503A nominations list updated 2024-09-27 states that it “has been removed from Category 2 because FDA received additional information from the nominator indicating that they intended to nominate a different bulk drug substance.” FDA’s safety-risk page (current version dated 2026-04-22) keeps selank acetate in its table of withdrawn substances with the stated concern of immunogenicity from aggregation and peptide-related impurities. Selank does not appear in any category of the nominations list updated 2026-05-14, was not among the substances reviewed by the Pharmacy Compounding Advisory Committee in December 2024 or July 2026, and is not on the 503A bulks list (21 CFR 216.23). This article therefore records compounding status as unknown.
Russia: registered in 2009 as “Selank 0.15%” nasal drops, according to the developing institute. Registration by a national regulator outside the US is not FDA approval.
