Crystagen

What it is

Crystagen belongs to the cytogens, very short synthetic peptides that the gerontologist Vladimir Khavinson and his institute have been developing for decades. The sequence is Glu-Asp-Pro. In the group’s laboratory papers it also appears under the code T-36, and in reviews simply as EDP.

Crystagen is assigned to the immune system. A 2021 review by the group describes that EDP was found together with the dipeptides Vilon and Thymogen in the thymus extract Thymalin. The idea behind it: the short peptide is supposed to carry part of the extract’s effect while being chemically clearly defined.

Crystagen is sold mainly as a capsule from Russia, where the manufacturer lists it as a dietary supplement and explicitly not as a medicine. The manufacturer states the composition as a peptide complex of proline, glutamic acid and aspartic acid.

Distinction from Thymalin, Vilon and Cortagen

Thymalin is a mixture of many peptides from calf thymus that is injected. Crystagen, by contrast, is a single small molecule. In spleen cultures, according to the 2021 review, Thymalin had a stronger effect than the individual peptides; the authors explain this by the extract containing all three short peptides and many more.

Vilon (Lys-Glu) and Thymogen (Glu-Trp) are the siblings from the same family. In a study on aging lymphocyte cultures, both slowed cell death more clearly than EDP. Cortagen, in turn, also ends in Glu-Asp-Pro, but has one more alanine at the front and is assigned to the brain, not the immune system.

How it is supposed to work

The Khavinson school assumes that very short peptides enter the cell nucleus, attach to DNA and histones and thereby change the reading of certain genes. For EDP, the group calculated in a computer model in 2016 which DNA sections it could bind to; it shared the binding site with Vilon. Two model calculations from 2022 and 2023 suggest that transporters such as PEPT1 or LAT1 could channel such short peptides into cells.

In the immune system, Crystagen is supposed to support above all the maturation and division of lymphocytes, which declines with age. Cell findings fit this: EDP increased the spontaneous division of normal human lymphocytes and the division of human thymic epithelial cells. This is an internally consistent hypothesis with cell and animal findings. Of this, only the change in blood values in a single study has been measured in humans.

In the laboratory, the effect is not entirely limited to the immune system. In a 2012 study, T-36 also stimulated cell division in skin cultures from young rats; in skin cultures from old animals, only a different tripeptide had a clear effect there. This shows two things: the peptide is biologically active, and the effect depends strongly on tissue and age.

What the studies show

Patent study in older patients, 2006

In the patent specification by Khavinson and colleagues, 38 patients aged between 62 and 83 with impaired immune values received Crystagen injections for 10 days in addition to their usual treatment; 32 patients served as controls. Normalized immune values were found in 82 percent versus 56 percent. No randomization or blinding is described, and the study is documented only in the patent specification.

Thymus and spleen of old rats

Tissue pieces from the thymus and spleen of 24-month-old rats were treated with EDP in culture. The growth area increased by 24 and 28 percent respectively. In the irradiation experiment in young rats, the thymus structure was better preserved. Both experiments come from the patent specification.

Aging spleen in comparison, 2014

Chervyakova and colleagues compared Vilon, Thymogen, Crystagen and another peptide on aging spleen tissue. Crystagen activated B cells but did not bring about any renewal of cells in the aging spleen. Vilon and Thymogen performed better on this point.

Immune and tumor cells, 2011

Khavinson and colleagues tested EDP under the code T-36 on human lymphocytes, granulocytes and cell lines. T-36 increased the spontaneous division of normal lymphocytes but left other functions of the immune cells unchanged. On the leukemia cell line K-562, the abstract contradicts itself.

Where the data stop

The data base is narrow. Under the name Crystagen, PubMed finds exactly 1 paper and Europe PMC 3, all from the circle of the St. Petersburg institute. There is no independent replication, and no study is registered in the ClinicalTrials.gov registry. The only human study was open and not randomized, and the endpoint, normalized immune values, is a laboratory finding, not protection against infections.

There are also inconsistencies. The 2021 review describes the human study as oral intake, the cited patent specification as intramuscular injection. Precisely this question matters, because the products sold are capsules and nobody has measured in humans whether the tripeptide arrives intact in the immune system after swallowing. The transport studies are computer models. A use in athletes, combined with other peptides, comes from a methodological recommendation without published participant numbers.

Status, approval and legal

Crystagen is approved in Germany and the EU neither as a medicine nor as a dietary supplement, and there is no approval in the US either. In Russia, according to its own information, the manufacturer lists it as a dietary supplement, not as a medicine. The peptide is patented as an agent against age-related disorders of immune defense (RU 2301074, WO2007139435). In sport, Crystagen as a non-approved substance falls under group S0 of the WADA Prohibited List 2026 and is therefore prohibited at all times.

Safety

There are no reliable safety data in humans. The patent specification reports toxicity tests in mice, in rats over 90 days and in guinea pigs over 6 months without toxic findings, and no side effects are described for the 10-day patient study. That is encouraging but does not replace systematic recording. Pharmacokinetics and interactions have not been studied in humans, and there are no upper limits from authorities. Because Crystagen is supposed to stimulate the division of immune cells, the question belongs in a doctor’s hands in autoimmune diseases, after transplantations, in blood cancer, and during pregnancy and breastfeeding. Gray-market products are not tested for purity and content.

Sources

• Khavinson et al., Biology Bulletin Reviews 2021 – Thymalin and its short peptides EW, KE, EDP
• Khavinson et al., patent WO2007139435 – Glu-Asp-Pro with immunogeroprotective effect
• Chervyakova et al., Adv Gerontol 2014 – short peptides in the aging spleen
• Khavinson et al., Bull Exp Biol Med 2011 – tripeptides on immune and stem cells
• Voicekhovskaya et al., Bull Exp Biol Med 2012 – tripeptides on skin cultures, T-36 is Glu-Asp-Pro
• Khavinson et al., Bull Exp Biol Med 2016 – short peptides and DNA binding in a model
• Khavinson et al., Int J Mol Sci 2022 – transport of ultrashort peptides
• Khavinson et al., Biomolecules 2023 – transport of 26 short peptides in a model
• NADA, WADA Prohibited List 2026 (informational German translation)