Thymalin vs Vilon vs Thymogen: One Research Line, Three Compounds
All three come from the same thymic work in the Khavinson programme. One is an extract, two are defined dipeptides, and only two hold any regulatory approval.
The Short Answer
Three compounds, one research line, and the differences are structural rather than functional. Thymalin is a first-generation extract from thymus tissue — a mixture. Vilon (Lys-Glu) and Thymogen (Glu-Trp) are second-generation synthesised dipeptides with defined sequences.
The relationship, in plain language: think of a traditional dish that a family made for generations without writing anything down. Thymalin is that dish — reliable, long-established, but never precisely specified. Then two people set out to write the recipe, and each arrived at a slightly different version they believed captured the essential part. Vilon and Thymogen are those two written recipes: shorter, exact, reproducible, and not identical to each other.
What Separates Them
Thymalin has the longest clinical history — approved for medical use in Russia since the 1980s as an immunomodulator, with decades of prescribing behind it. Being an extract, it cannot carry a meaningful purity figure in the way a synthesised peptide can.
Thymogen (Glu-Trp) was also introduced into Soviet medical practice and holds Russian registration. It is among the shortest molecules ever registered as a medicine anywhere — two amino acids.
Vilon (Lys-Glu) is the outlier of the three: a defined dipeptide with a small, largely preclinical literature and no regulatory approval in any jurisdiction, including Russia.
All three are studied for T-cell maturation and immune recalibration rather than immune stimulation — the distinction being between retuning a system and simply pushing it harder.
Frequently Asked Questions
Compiled by the Southern Pacific Labs research team. Last updated July 2026.
Published References
- Khavinson VK, Malinin VV. “Gerontological Aspects of Genome Peptide Regulation.” Karger AG, Basel, 2005. Source
- Anisimov VN, Khavinson VKh. “Peptide bioregulation of aging: results and prospects.” Biogerontology, 2010. PubMed
- Khavinson VKh. “Peptides and Ageing.” Neuro endocrinology letters, 2002. PubMed
- Fedoreyeva LI, Kireev II, Khavinson VKh, et al. “Penetration of short fluorescence-labeled peptides into the nucleus in HeLa cells and in vitro specific interaction of the peptides with deoxyribooligonucleotides and DNA.” Biochemistry. Biokhimiia, 2011. PubMed
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