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Thymalin: quick citable summary
Thymalin is listed by PeptaHub as a immune peptide with a research only legal-status classification. The page summarizes mechanism, research context, common routes, safety notes, and references for writers and AI answer engines.
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What is Thymalin?
Thymalin is a thymic peptide bioregulator used in Russian medicine since 1982 for immune restoration. One non-randomized 6-8 year cohort of 266 elderly people reported mortality 2.0-2.1-fold lower in the thymalin group, a result never independently replicated.
Overview
Thymalin is a thymic peptide bioregulator developed by Vladimir Khavinson (the same researcher behind Epithalon) from bovine thymus extracts. It has been used in Russian clinical medicine since 1982 for immune system restoration, particularly in immunocompromised patients and the elderly. Khavinson's long-term non-randomized observational cohort reported lower mortality in elderly patients given thymalin, a finding that has not been independently replicated.
Mechanism of action
Thymalin is proposed to modulate T-cell differentiation and maturation. In human hematopoietic stem cell culture it reduced the stem/progenitor markers CD44 and CD117 and raised CD28, a mature T-lymphocyte marker, which the authors read as a push toward T-cell differentiation. In the human THP-1 monocytic cell line it suppressed LPS-stimulated TNF and IL-6 release. The broader claims made for it in Russian practice literature (CD4/CD8 normalization, NK activity, phagocytosis, reversal of age-related thymic involution) do not have indexed trial data behind them and remain hypotheses.
Reported study ranges
| Purpose | Route | Reported range | Frequency | Notes |
|---|---|---|---|---|
| immune restoration / anti-aging | intramuscular | 5–10 mg | daily | Standard Russian protocol: 5-10mg daily for 5-10 days. Repeat courses every 3-6 months. Often combined with Epithalon. |
Reported ranges are for research context only. Consult a qualified healthcare professional before using any peptide.
Convert Thymalin research-range units
Need to convert mg to mcg, dose volume, or U-100 syringe units? The Thymalin dose calculator is preloaded with these ranges, or use the general dose unit converter.
Research summary
Khavinson and Morozov (Neuro Endocrinol Lett 2003) clinically followed 266 elderly and older persons for 6-8 years, giving thymic (Thymalin) and pineal (Epithalamin) bioregulators during the first 2-3 years. Relative to controls, they reported a 2.0-2.1-fold lower mortality rate in the Thymalin group, 1.6-1.8-fold in the Epithalamin group, and 2.5-fold in the combined group, alongside a 2.0-2.4-fold drop in acute respiratory disease incidence. The study was not randomized or placebo-controlled and has not been independently replicated. Mechanistic work in human hematopoietic stem cell culture (Bull Exp Biol Med 2020) found thymalin shifted marker expression toward mature T lymphocytes. Approved in Russia since 1982. Limitations: most research is by a single group in Russian journals with no Western replication.[1][2][3][4]
Evidence grading
Each claimed benefit is graded by the strength of available evidence. Grades reflect study quality, not effect size.
Strong = multiple RCTs · Moderate = limited trials or observational · Preliminary = animal or in vitro only · Insufficient = anecdotal or no published data
Side effects
Side effects vary by individual. This is not an exhaustive list. Report unusual symptoms to a healthcare professional.
Common stacks
Peptides commonly paired with Thymalin for synergistic effects.
Legal status
Approved in Russia as a pharmaceutical since 1982. Not FDA-approved. Available as a research peptide internationally. Part of Khavinson's peptide bioregulator system.
Sourcing & access
Research compound
Thymalin is classified as a research compound. Regulatory status varies by jurisdiction. Always verify current legal status and source from vendors providing third-party certificates of analysis (COA).
Frequently asked questions
Thymalin is a peptide bioregulator derived from bovine thymus extracts, developed by Vladimir Khavinson. It has been approved and used in Russia since 1982 for immune restoration in immunocompromised patients and the elderly.
In cell culture, thymalin shifted human hematopoietic stem cells toward mature CD28-positive T lymphocytes and suppressed LPS-stimulated TNF and IL-6 in a monocytic cell line. Wider claims about CD4/CD8 normalization, NK cell activity and reversing age-related thymic involution come from Russian practice literature rather than indexed trials, so treat them as unconfirmed.
Thymalin has over 40 years of clinical use in Russia. Side effects include injection site reactions, mild allergic reactions (rare), and low-grade fever from immune activation. It is not FDA-approved and is available internationally as a research peptide.
Khavinson and Morozov followed 266 elderly people for 6-8 years and reported mortality 2.0-2.1-fold lower in the thymalin group and 2.5-fold lower with thymalin plus epithalamin, versus controls. The study was not randomized or placebo-controlled, and no group outside Khavinson's has replicated it. Separate cell-culture work suggests thymalin pushes hematopoietic stem cells toward mature T lymphocytes.
Research references
- Peptides of pineal gland and thymus prolong human lifePubMed
- [Geroprotective effect of thymalin and epithalamin] (Russian-language)PubMed
- Thymalin: Activation of Differentiation of Human Hematopoietic Stem CellsPubMed
- Peptides Regulating Proliferative Activity and Inflammatory Pathways in the Monocyte/Macrophage THP-1 Cell LinePubMed