Thymalin is a peptide preparation extracted from calf (bovine) thymus tissue, characterized principally in Russian immunology and gerontology research by Vladimir Khavinson and colleagues at the Institute of Bioregulation and Gerontology in St. Petersburg. The preparation is a complex mixture of short peptides (predominantly di-, tri-, and tetra-peptides) characterized in the historical research literature as having immunomodulatory activity in models of immune dysfunction and gerontological-research interest in age-related immune decline. It is not a single defined peptide molecule.

Is Thymalin the same as thymosin alpha-1?

No. Thymalin is a tissue-extract peptide preparation from the Russian/Soviet thymic-peptide research line (Khavinson laboratory). Thymosin alpha-1 is a distinct, structurally defined 28-amino-acid synthetic peptide derived from a separate Western research line (Goldstein laboratory at George Washington University) and developed clinically by SciClone Pharmaceuticals and others. Thymosin alpha-1 is approved as Zadaxin in some jurisdictions for specific indications including hepatitis B. The two molecules are entirely distinct.

Is Thymalin approved as a medicine?

Thymalin has historical regulatory status in Russia and some post-Soviet jurisdictions as an immunomodulatory preparation. It is NOT approved by the US FDA, the European Medicines Agency, or other major Western regulatory authorities for any indication. The regulatory frameworks for tissue-extract peptide preparations differ substantially between jurisdictions, and the historical Russian regulatory status does not translate to Western regulatory approval. The research-supply context of this page is academic understanding only.

What is the composition of Thymalin?

Thymalin is a complex mixture of short peptides (predominantly di-, tri-, and tetra-peptides) extracted from calf thymus by acid extraction and chromatographic purification. One specific component is the dipeptide Glu-Trp (subsequently named thymogen). Other components include longer peptides and polypeptide fragments derived from thymic-tissue proteins. The overall composition is characterized by the extraction methodology and peptide-fragment profile rather than by identification of a single primary active component.

Thymogen is the synthetic dipeptide Glu-Trp (glutamyl-tryptophan), identified through analytical fractionation of the Thymalin extract by the Khavinson research group as one defined-structure component of the broader peptide mixture. Thymogen is characterized in the published literature as a distinct research compound in its own right; it can be considered as one well-characterized molecular component of the Thymalin extract, although the biological activity of the Thymalin preparation is attributed to multiple peptide components acting collectively.

Who developed Thymalin?

Thymalin was developed and characterized in the Russian/Soviet immunology and gerontology research line at what is now the Institute of Bioregulation and Gerontology in St. Petersburg, principally by Vyacheslav Morozov, Vladimir Khavinson, and colleagues, beginning in the 1970s. The Khavinson research program has been the principal source of Thymalin literature and has continued to publish on the molecule and on the broader 'regulatory peptide' research portfolio for several decades.

What is the difference between Thymalin and epitalon?

Both are 'regulatory peptides' from the same Khavinson research program. Thymalin is a tissue-extract peptide mixture from calf thymus. Epitalon is a synthetic tetrapeptide (Ala-Glu-Asp-Gly) derived from pineal-gland research in the same research program. The two have different tissue sources (thymus vs. pineal), different molecular characteristics (extract mixture vs. defined synthetic peptide), and different proposed application areas (immunomodulation/immunosenescence vs. pineal-derived longevity-research peptide), but they share the same Russian research-program origin.

What is the relationship between Thymalin and the thymus?

Thymalin is extracted from calf thymus tissue and is hypothesized in the historical research literature to contain peptide components that reflect or modulate thymic function. The thymus is the central primary lymphoid organ for T-cell development; thymic involution and the associated decline in naïve T-cell output is a hallmark of aging biology. The research-program hypothesis is that thymic-derived peptide signals can be characterized and used as research-tool modulators of immune function. The molecular basis of this hypothesis is more defined for some Western synthetic thymic peptides (e.g., thymosin alpha-1) than for the Thymalin tissue-extract preparation.

Has Thymalin been studied in clinical research?

Thymalin has been used in human-research cohorts and clinical-use contexts in Russia and some post-Soviet jurisdictions in the context of its historical regulatory status in those jurisdictions. Published reports include immunological endpoints in various patient populations. These reports represent historical clinical-research and registered-medicine use in the relevant national regulatory frameworks; the methodology and reporting practices differ from contemporary Western clinical-research standards. Thymalin has not been the subject of Western clinical-research programs.

Is Thymalin a defined chemical entity?

No. Thymalin is a tissue-extract peptide preparation characterized as a complex mixture of short peptides extracted from calf thymus. It is not a single defined chemical entity. The preparation is characterized by its extraction methodology and peptide-fragment profile rather than by a single primary sequence. This is distinct from the structurally defined synthetic thymic peptides (thymosin alpha-1, thymopentin, thymogen) that are single defined molecules.

How does Thymalin differ from thymopentin?

Thymalin is a Russian-developed tissue-extract peptide preparation from calf thymus. Thymopentin (TP-5) is a synthetic pentapeptide (Arg-Lys-Asp-Val-Tyr) corresponding to residues 32-36 of the thymic hormone thymopoietin, developed in a separate Western research line. The two are entirely distinct: Thymalin is an extract preparation, thymopentin is a defined synthetic peptide; the research-programs of origin are different; and the proposed pharmacologies are characterized separately in different bodies of literature.

Is Thymalin a 'natural' product?

Thymalin is derived from animal tissue (calf thymus) by acid extraction and chromatographic purification. The starting material is biological; the extraction and purification process is a defined laboratory or manufacturing methodology. Characterization of 'natural' vs. 'synthetic' is somewhat artificial for tissue-extract peptide preparations — the preparation is a defined biological extract with characterized composition, not a wild-collected raw material and not a synthetic peptide.

How is research-supply Thymalin stored?

Research-supply Thymalin is supplied as a sterile lyophilized peptide-mixture preparation in a sealed vial. Lyophilized storage is at -20 °C or below in a moisture-protected container. Reconstituted solutions in aqueous diluent are stored refrigerated (2-8 °C) and used within a short window per standard peptide-mixture-stability practice. The specific storage instructions depend on the specific source preparation and are described on the supplier's product certificate.

Why is Thymalin in a research-supply catalog if it has Russian medical use?

The research-supply context of this catalog is academic and laboratory use for understanding the historical thymic-peptide research literature, including the Russian research line led by the Khavinson laboratory. The historical Russian/post-Soviet regulatory and clinical-use status of Thymalin is separate from the Western research-supply context and is not part of the FDA, EMA, or equivalent Western regulatory framework. The research-supply context is academic and does not constitute or endorse any medical-use recommendation.

Thymalin 10mg (with Bacteriostatic Water) lyophilized vial with bacteriostatic water for research

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Thymalin 10mg (with Bacteriostatic Water)

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Thymalin is a thymus-derived peptide complex extensively studied in immunology, cellular signaling, and healthy aging research. Originally developed from peptide fractions isolated from the thymus gland, Thymalin has been investigated for its role in immune system regulation, cellular communication, and age-related biological processes. Manufactured to rigorous laboratory standards, our Thymalin 10mg research peptide undergoes comprehensive quality testing to ensure purity, consistency, and reliability for scientific investigation.

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