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Thymalin

Also known as: Thymus Bioregulator, Thymus Peptide Extract, Thymarin

Thymalin is a polypeptide complex isolated from calf thymus glands (developed by the Russian Gerontology Institute), shown to restore immune function, extend lifespan, and reverse thymic involution. Clinical studies demonstrate improved immune parameters and up to 40% reduction in mortality in elderly patients.

Half-Life

Not well characterized as a complex extract; individual peptides have varying kinetics

Route

SubQ, IM

Category

Immune Support, Anti-Aging & Longevity

Studies

30 references

Key Benefits

  • Restores thymic function and T-cell immunity
  • Extends healthy lifespan (documented in long-term studies)
  • Reduces infectious disease incidence in elderly
  • Normalizes immune parameters in immunodeficiency
  • Anti-tumor immune surveillance
  • Improves vaccine response in elderly
  • Reduces cardiovascular mortality (40% in landmark Russian study)
  • Normalizes neuroendocrine function

Mechanism of Action

Thymalin is a natural thymus gland extract containing multiple low-molecular-weight peptides (including thymosin, thymulin, thymopentin, and others) that restore T-lymphocyte maturation and differentiation. The thymus involutes with age, impairing cellular immunity. Thymalin reactivates thymic function, increasing CD3+, CD4+, CD8+ T-cells, NK cells, and normalizing T-helper/T-suppressor ratios. It also stimulates cytokine production (IL-1, IL-2, IFN-γ) and enhances phagocytic activity. Long-term use has demonstrated neuroendocrine normalization and measurable lifespan extension in animal and human studies.

Dosing Protocols

Immune Restoration / Longevity Protocol

Dose
10 mg IM or SC daily
Frequency
Once daily
Timing
Any time of day
Cycle
10-day course, 1–3x per year

Classic Russian protocol: 10 mg/day for 10 days, repeated annually; landmark Khavinson study used this protocol over 6–8 years

Maintenance Anti-Aging

Dose
5–10 mg SC
Frequency
Daily for 10 days
Timing
Same time each day
Cycle
10 days every 6 months

Minimum effective protocol; higher frequency may be used in severe immunodeficiency

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Side Effects

  • Very well tolerated in decades of Russian clinical use
  • Mild injection site reactions
  • Rare: mild allergic reaction (natural extract)
  • Transient flu-like symptoms on initiation (immune activation)

Contraindications

Caution in autoimmune diseases (immune stimulation may worsen). Not recommended in organ transplant patients (may provoke rejection). Avoid in atopic allergy to bovine products.

Storage

Store at 2–8°C. Protect from light. Reconstituted solution use within 24 hours. Lyophilized vials: up to 2 years at refrigerator temperature.

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  3. 3.
    The Influence of KE and EW Dipeptides in the Composition of the Thymalin Drug on Gene Expression and Protein Synthesis Involved in the Pathogenesis of COVID-19

    Linkova N, Khavinson V, Diatlova A, Petukhov M, Vladimirova E, Sukhareva M et al. · International journal of molecular sciences · 2023PubMed Verified

  4. 4.
    Peptides Regulating Proliferative Activity and Inflammatory Pathways in the Monocyte/Macrophage THP-1 Cell Line

    Avolio F, Martinotti S, Khavinson VK, Esposito JE, Giambuzzi G, Marino A et al. · International journal of molecular sciences · 2022PubMed Verified

  5. 5.
    Results and Prospects of Using Activator of Hematopoietic Stem Cell Differentiation in Complex Therapy for Patients with COVID-19

    Khavinson VK, Kuznik BI, Trofimova SV, Volchkov VA, Rukavishnikova SA, Titova ON et al. · Stem cell reviews and reports · 2021PubMed Verified

  6. 6.
    Thymalin: Activation of Differentiation of Human Hematopoietic Stem Cells

    Khavinson VK, Linkova NS, Kvetnoy IM, Polyakova VO, Drobintseva AO, Kvetnaia TV et al. · Bulletin of experimental biology and medicine · 2020PubMed Verified

  7. 7.
    Effect of Thymalin on the Tumor and Thymus under Conditions of Activation Therapy In Vivo

    Zhukova GV, Schikhlyarova AI, Barteneva TA, Shevchenko AN, Zakharyuta FM · Bulletin of experimental biology and medicine · 2018PubMed Verified

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    Chrono- and Immunocorrection of Inflammatory Disorders of Internal Reproductive Organs in Women of Reproductive Age

    Litvinenko GI, Shurlygina AV, Dergacheva TI, Mel'nikova EV, Trufakin VA · Bulletin of experimental biology and medicine · 2015Clinical TrialPubMed Verified

  10. 10.
    New data on the involvement of ectodermal epithelium in extrathymic differentiation of human T-lymphocytes

    Khlystova ZS, Kalinina II, Shmeleva SP · Bulletin of experimental biology and medicine · 2004PubMed Verified

  11. 11.
    Immuno-, phagocytosis-modulating, and antitoxic properties of amino acids and peptide preparations

    Belokrylov GA, Derevnina OY, Molchanova IV, Sorochinskaya EI · Drug development and industrial pharmacy · 1998PubMed Verified

  12. 12.
    Peptides of pineal gland and thymus prolong human life

    Khavinson VKh, Morozov VG · Neuro endocrinology letters · 2003RCTPubMed Verified

  13. 13.
    Thymalin in developing respiratory organs of human fetus

    Khlystova ZS, Kalinina II, Shmeleva SP · Bulletin of experimental biology and medicine · 2003PubMed Verified

  14. 14.
    Modulating and protective effects of thymic peptides in lymphoid tissue culture

    Chalisova NI, Khavinson V, Nozdrachev AD · Doklady biological sciences : proceedings of the Academy of Sciences of the USSR, Biological sciences sections · 2001PubMed Verified

  15. 15.
    Modern Immunotherapy in Clinical Medicine: Present and Future

    Nesterova IV · Russian journal of immunology : RJI : official journal of Russian Society of Immunology · 1999PubMed Verified

  16. 16.
    Contemporary Views on the Nature and Clinical Application of Thymus Preparations

    Arion VY, Zimina IV, Lopuchin YM · Russian journal of immunology : RJI : official journal of Russian Society of Immunology · 1997PubMed Verified

  17. 17.
    Age-related changes of thymalin content in human epidermis

    Khlystova ZS, Kalinina II, Shmeleva SP, Ryabchikov OP, Khavinson VKh · Bulletin of experimental biology and medicine · 2002PubMed Verified

  18. 18.
    Thymic hormones in human fetal skin epidermis

    Khlystova ZS, Kalinina II, Khavinson VKh · Bulletin of experimental biology and medicine · 2002PubMed Verified

  19. 19.
    Peptides and Ageing

    Khavinson VKh · Neuro endocrinology letters · 2002ReviewPubMed Verified

  20. 20.
    Immunomodulatory synthetic dipeptide L-Glu-L-Trp slows down aging and inhibits spontaneous carcinogenesis in rats

    Anisimov VN, Khavinson VK, Morozov VG · Biogerontology · 2000PubMed Verified

  21. 21.
    Development of endocrine and lymphocytopoietic functions of the thymus in human embryogenesis

    Khlystova ZS, Kalinina II, Shmeleva SP, Ryabchikov OP · Bulletin of experimental biology and medicine · 2000PubMed Verified

  22. 22.
    Natural and synthetic thymic peptides as therapeutics for immune dysfunction

    Morozov VG, Khavinson VK · International journal of immunopharmacology · 1997PubMed Verified

  23. 23.
    Lysosomal glycosidases in different populations of human thymocytes

    Ushakova NA, Sirina EG, Preobrazhenskaya ME, Yarilin AA · Biochemistry and molecular biology international · 1995PubMed Verified

  24. 24.
    Norcolut with immune modulators in the complex treatment for hyperplastic uterine processes

    Zaporozhan VN, Khait OV, Tumasyan KP · Clinical and experimental obstetrics & gynecology · 1993PubMed Verified

  25. 25.
    Age-dependent experimental tumor dissemination of murine melanoma B16

    Baumgart J, Zippel D · Archivum immunologiae et therapiae experimentalis · 1991PubMed Verified

  26. 26.
    Application of thymic factor "Thymalin" in complex treatment of endometrial cancer patients

    Bakhidze EV, Bokhman JaV · European journal of gynaecological oncology · 1990PubMed Verified

  27. 27.
    Age-dependent antileukemic action and suppression of immune response by 1,4-benzoquinone-guanylhydrazone-thiosemicarbazone (ambazone) in mice

    Baumgart J, Wisniewski HG, Amlacher R, Zhukovskaya NV, Rentz E · Neoplasma · 1989PubMed Verified

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    Experimental and clinical study of the thymus polypeptide factor thymalin

    Safronov BN, Morozov VG, Khavinson VKh, Belokrylov GA · Human physiology · 1984PubMed Verified

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Medical disclaimer: This information is for educational purposes only and does not constitute medical advice. Many compounds listed are research chemicals not approved for human use. Always consult a qualified healthcare professional before starting any protocol.

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