Thymalin
Also known as: Thymic Factor, Thymalin Lys-Glu
A polypeptide complex derived from the thymus gland of young calves, developed in the 1970s at the USSR Institute of Gerontology. Russian clinical studies report significant immune restoration and reduced mortality in elderly patients, though independent Western replication is limited.
How it works
Thymalin contains short peptides (2-8 amino acids) extracted from calf thymus tissue that regulate gene expression in immune and blood-forming cells. It works by helping restore thymus gland function, which naturally shrinks and weakens with age. The thymus is where T-cells mature, so supporting it can improve the body's immune surveillance. It is part of a class called 'bioregulator peptides' developed in Russian gerontology research.
Common uses
- Immune system restoration in elderly patients
- Anti-aging and longevity protocols
- Thymus gland function support
- Bioregulator peptide therapy
Side effects
- Generally well-tolerated in Russian clinical studies
- Injection site reactions
- Mild flu-like symptoms possible
- Allergic reactions possible (animal-derived product)
- Limited Western safety data
Key research
- Russian 6-year longitudinal study in elderly patients showed 2-4x reduced mortality in Thymalin-treated groups compared to controls
- COVID-19 study showed Thymalin helped regulate immune status in severe cases in older patients
- Combined Epithalon + Thymalin protocols showed synergistic anti-aging effects in Russian clinical studies
Safety notes
- Not FDA-approved and not available through US compounding pharmacies
- Evidence base comes primarily from a single Russian research institution
- Results have not been independently replicated by Western randomized controlled trials
- Animal-derived product carries theoretical allergy risk
- Distinct from Thymosin Alpha-1, which is a defined single peptide rather than a complex extract
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