Vilon peptide: what the Khavinson thymus dipeptide is, what the studies show and what is unknown

Vilon is the trade name for the dipeptide Lys-Glu: one lysine joined to one glutamic acid. In the single-letter code used in most of the recent papers it is written KE, so vilon, KE peptide and Lys-Glu peptide all refer to the same molecule. Sellers list it as the vilon bioregulator or vilon thymus peptide. It belongs to the family of short synthetic peptides developed by Vladimir Khavinson and colleagues at the St Petersburg Institute of Bioregulation and Gerontology, who call them peptide bioregulators or cytogens. Vilon was designed from the amino acid composition of Thymalin, a polypeptide extract of calf thymus, on the theory that a very short peptide could reproduce the tissue-specific activity of the extract it came from ^{[3] [4]}.

That design principle is the origin of the whole series. Dipeptides were assigned to the thymus, and tetrapeptides to the heart, liver, brain cortex and pineal gland; epitalon, the best known of the group, is the pineal tetrapeptide, and thymalin is the thymus extract vilon was modelled on ^[3]. In organ culture, each short peptide was reported to stimulate the growth of explants only from the tissue whose extract had been used to design it, so vilon stimulated thymus explants while cortagen stimulated brain cortex and livagen stimulated liver ^[4].

Because the same group produced almost all of the evidence, and because much of it appeared in Russian-language journals such as Advances in Gerontology (Uspekhi Gerontologii) with only an English abstract, readers should treat vilon claims with more caution than they would a peptide with independent replication. The main English-language outlet is the Bulletin of Experimental Biology and Medicine, a translated Russian journal that is indexed in PubMed. That is where most of the citations in this guide come from.

The developers describe vilon as a thymomimetic, meaning it is intended to imitate the effect of thymic peptides on immune cells. In mouse thymocytes, vilon produced the strongest co-mitogenic effect of three peptides tested (the others were epitalon and cortagen), modulated the activity of interleukin-1 beta and increased sphingomyelinase activity in thymocyte membranes, which the authors read as a sign that it works through the sphingomyelin signalling pathway ^[5]. In co-culture with human thymocytes and thymic epithelial cells, vilon increased the expression of argyrophilic nucleolar proteins, a marker of ribosome production and protein synthesis, and directly pushed thymocytes to transform into proliferating blast cells; epitalon did the opposite ^[6].

The group’s more recent explanation is epigenetic. In a 2015 study, Lys-Glu stimulated the growth of spleen cell cultures while an equal mixture of free lysine and glutamic acid inhibited it, and molecular docking suggested that the intact dipeptide binds the minor groove of DNA more strongly than either amino acid alone ^[14]. A 2023 report in Advances in Gerontology found that the KE peptide increased SIRT1 gene expression and protein by six- and eight-fold in young human mesenchymal stem cells, and reduced PARP1 and PARP2 expression during replicative ageing; the authors again proposed direct binding to promoter sequences ^[15]. A 2020 study in Molecular Biology Reports, with independent co-authors from Moscow State University, found that KE at nanomolar concentrations raised IGF1 and NF-kB gene expression in ageing human mesenchymal stem cells and roughly doubled FOXO1 expression in one of two ageing models ^[16].

Direct peptide-DNA binding as a mechanism for dipeptides remains a hypothesis from this group. The docking studies are computer models, and the cell studies measure gene expression changes without showing that the peptide reaches the nucleus in the concentrations modelled. No independent laboratory has, to our knowledge, confirmed that Lys-Glu regulates these genes in living tissue.

Lifespan and tumours in mice: the most cited vilon paper is the 2000 mouse study. Female CBA mice given subcutaneous vilon from the sixth month of life showed increased physical activity and endurance, lower body temperature, a longer lifespan and fewer spontaneous tumours than controls, with no effect on oestrous cycling or free-radical measures and no reported harm from long-term dosing ^[1]. A companion report the same year described the dipeptide inhibiting spontaneous tumour growth and increasing lifespan ^[2]. In a chemical carcinogenesis model, mice treated with vilon at 10 µg/kg after 1,2-dimethylhydrazine developed tumours in 14.3% of survivors compared with 60% of controls, and pre-cancerous kidney changes were also reduced ^[8]. These are the results that underpin the geroprotector and oncostatic labels the group uses, and they have not been repeated by anyone outside it.

Immune recovery after radiation: in rats given a single 6 Gy whole-body dose, vilon stimulated thymocyte proliferation and the proliferative potential of intestinal stem cells, which the authors interpreted as faster recovery of radiosensitive organs; epitalon in the same experiment slowed duodenal metabolism and suppressed blood cell formation in the spleen ^[7]. In a low-dose radiation model of premature ageing of the thymus and spleen, vilon partly inhibited the process ^[18].

Kidney and blood vessels: in rats with experimental chronic renal failure, subcutaneous vilon lowered serum transforming growth factor-beta and reduced leakiness of mesenteric microvessels two months after the kidney injury, but not at four or six months ^[13]. Sexual function and hormones: in old hemigonadectomised male rats, regular vilon at 50 µg per rat increased sexual activity and lowered prolactin, with changes in LH, ACTH and hypothalamic neurotransmitters ^[12]. Stress: intraperitoneal vilon raised resistance to emotional stress in Wistar rats, limited adrenal enlargement and thymus shrinkage, and reduced the number of activated neurons in the paraventricular hypothalamus ^[19].

Skin and inflammation in cell culture: KE, together with KED (vesugen), AED and AEDG (epitalon), reduced MMP-9 and raised the proliferation marker Ki-67 in ageing skin fibroblast cultures ^[20]. A 2022 study by an Italian group with Khavinson as co-author found that five Khavinson peptides, including vilon, increased tyrosine phosphorylation of MAP kinases in the THP-1 monocyte line and reduced TNF and IL-6 release after bacterial lipopolysaccharide, which the authors framed as inducing TNF tolerance ^[17]. That is a cell-line result and says nothing about inflammation in people.

Chromatin in old people’s cells: in lymphocytes taken from people aged 75 to 88, vilon, epitalon, livagen, prostamax and cortagen all activated ribosomal genes and loosened condensed chromatin, although vilon, unlike the tetrapeptides, did not decondense pericentromeric heterochromatin on chromosomes 1 and 9 ^[21]. These were laboratory treatments of cultured cells, not treatment of the donors.

We found no randomised, placebo-controlled trial of vilon in any condition, and no entry for it on ClinicalTrials.gov as of September 2026. What exists are Russian-language clinical reports, published with English abstracts in Advances in Gerontology, from centres associated with the developers.

Type 1 diabetes: a 2006 report from Chita State Medical Academy described a chronic low-grade intravascular coagulation state in patients with unstable type 1 diabetes and stated that adding vilon to standard treatment significantly reduced or abolished it, with a weaker effect in elderly patients with severe disease ^[9]. A 2007 follow-up from the same group reported that vilon added to complex therapy raised natural anticoagulants (antithrombin III and protein C), stimulated fibrinolysis, reduced the insulin dose needed in most patients, and normalised several lymphocyte and immunoglobulin measures ^[10]. Neither abstract gives patient numbers, a control group or blinding, so the size and reality of these effects cannot be judged.

Elderly cancer patients: a 2005 report described what it called pioneer experience of adding vilon, as an immunomodulator, to radical treatment of elderly patients with stage III colorectal cancer, and suggested on preliminary results that it might improve two-year survival and reduce complications and recurrence ^[11]. This is an uncontrolled clinical observation, and no follow-up publication with survival data has appeared in PubMed.

The developers’ own 2013 review of clinical results for peptide bioregulators, covering thymalin, thymogen, vilon, epithalamin and others, summarises decades of the group’s clinical use as geroprotectors ^[22]. Because it is a review by the developers of their own studies, it cannot substitute for independent trials. The honest summary is that vilon has been given to people in Russia for at least twenty years, that the published reports are positive, and that none of them meets the standard of evidence needed to say it works.

There is no human dose-response or time-course data. In the mouse lifespan study, vilon was given in courses from the age of six months until the end of life, and the outcomes were measured over the whole lifespan ^[1]. The rat renal failure study saw effects at two months but not later ^[13], and the old-rat sexual function study used regular dosing over weeks ^[12]. In the Russian clinical reports, effects on coagulation were described after a course of treatment alongside standard care, without a stated duration in the abstract ^{[9] [10]}. Anyone told that vilon works within days should ask which study shows that; we could not find one.

The following figures describe what published studies used. They are not recommendations, and no dose has been established for humans in a controlled trial. In rodents, vilon was given subcutaneously at 0.1 to 10 µg per animal or per kilogram: 10 µg/kg in the dimethylhydrazine carcinogenesis study ^[8], 50 µg per rat in the old-male sexual function study ^[12], and subcutaneous courses in the mouse lifespan study ^[1]. In cell culture, the group typically reports activity at concentrations in the nanogram-per-millilitre range, and the mesenchymal stem cell study used nanomolar concentrations ^[16].

The clinical reports in type 1 diabetes and elderly cancer patients do not state the dose or route in their English abstracts ^{[9] [10] [11]}. Research suppliers usually sell vilon as a lyophilised powder in 5 to 20 mg vials, which is a very different scale from the microgram doses in the animal work. If you are converting between vial contents, concentration and volume for a laboratory protocol, use the peptide calculator and the vilon-specific calculator page.

In the animal studies, vilon was given by subcutaneous injection ^{[1] [13]} or intraperitoneal injection ^[19]. Dipeptides can in principle survive the gut better than longer peptides, and the developers have modelled the transport of their short peptides through intestinal amino acid and peptide transporters (LAT1, LAT2 and PEPT1) ^[23]. In Russia, several Khavinson peptides are sold in capsule form as supplements rather than as injectable medicines, but we found no published pharmacokinetic study of vilon in humans by any route, so how much of an oral or injected dose reaches the thymus, and for how long, is unknown.

Because the molecule is so small, at about 275 g/mol, a certificate of analysis for vilon should show a single sharp peak at that mass on mass spectrometry. Free lysine and glutamic acid, or a dipeptide in the wrong order (Glu-Lys), would be hard to distinguish by HPLC alone, which is one reason to insist on mass-spectrometry data for this peptide in particular.

The mouse lifespan study reported no unfavourable effects from long-term subcutaneous dosing and described chronic administration as safe, but the study was designed to measure ageing outcomes rather than to detect toxicity ^[1]. No published human safety data exist beyond the unstated tolerability in the small Russian clinical reports. That means the common questions, whether vilon causes side effects, affects blood pressure, interacts with medicines or is safe in pregnancy, have no evidence-based answers.

Two theoretical concerns follow from the mechanism claims. First, a peptide that stimulates thymocyte proliferation and blast transformation ^[6] and raises NF-kB and IGF1 gene expression in stem cells ^[16] is, on the developers’ own account, growth-promoting in immune and stem cells; the same group reports fewer tumours in mice ^{[1] [8]}, but the two findings have not been reconciled by independent work. Second, the diabetes reports describe vilon reducing the insulin dose patients needed ^[10]; if that is real, adding vilon to insulin without monitoring would be a hypoglycaemia risk, and if it is not real, it illustrates how little can be relied on. Neither concern has been tested.

Vilon is not on the FDA’s list of bulk drug substances that may present significant safety risks in compounding, unlike epitalon and thymosin alpha-1, which were nominated and later withdrawn ^[24]. Absence from that list reflects that nobody nominated it, not that it was reviewed and found acceptable.

Vilon is not an approved medicine in the UK, US, EU, Canada or Australia. In the UK, a product sold for human use with claims about immunity or ageing would fall under medicines law regardless of the research-use label, and the MHRA has not licensed any vilon product. In the US it is not an FDA-approved drug and, as noted above, it has not been on the compounding category 2 list ^[24]. The Russian-language literature refers to vilon as a preparation used in clinical practice, and Khavinson peptides are marketed in Russia in supplement form, but we have not verified vilon’s current registration status there and readers should not assume a Russian supplement listing means approval elsewhere.

We have not confirmed whether vilon falls under any category of the WADA Prohibited List; short peptides that are not growth hormone secretagogues are not usually named, but athletes should check with their governing body. For the rules on buying and holding research peptides in your country, see our legal status overview, including the UK page, the US page and the Europe page.

Vilon is supplied as a freeze-dried powder. As a dipeptide with no cysteine or tryptophan it is chemically more stable than most research peptides, but the general rules still apply: keep the sealed vial cold, dry and away from light, and once reconstituted keep the solution refrigerated and use it within a limited period. See how to store peptides and our guide to bacteriostatic water for reconstitution practice.

Vilon is one of the cheapest peptides to synthesise, since it is only two amino acids, so a high price per milligram is not a sign of quality. Compare vilon prices across the stores we track, including listings in the UK and the US. Before buying, read how to read a peptide COA and check that the certificate shows a measured mass of about 275 g/mol, then look at our list of third-party tested suppliers.

Stores often bundle vilon with epitalon or thymalin as a vilon epitalon anti-ageing stack, citing the mouse and chromatin studies above. Our guides to third-party peptide testing, what research peptides are and how to spot a fake peptide supplier explain what a seller’s claims can and cannot be checked against. For the other tissue-specific peptides in the same series, see vesugen, pancragen, testagen and pinealon.