Thymalin
Thymus Peptide Bioregulator Complex
Mechanism of Action
A standardized polypeptide fraction isolated from calf thymus. Stimulates T-lymphocyte differentiation and maturation, helps normalize the CD4:CD8 ratio, enhances phagocytic activity, and supports cytokine regulation — effects attributed to short regulatory peptides acting on gene expression in thymic and immune tissue.
Key Benefits
- T-cell differentiation and immune competence support
- Normalization of age-related immune decline markers
- Reduced acute respiratory illness incidence reported in elderly cohorts (Khavinson trials)
- Studied alongside Epithalamin/Epitalon for longevity and mortality outcomes
Dosing Protocol
Classic Khavinson protocol runs short, intensive 10-day courses rather than continuous daily dosing. Frequently studied and administered alongside Epithalamin/Epitalon in Russian geroprotector research. Not the same product as Thymosin Alpha-1 (Zadaxin) despite similar names.
Ideal Candidates
Older adults researching age-related immune decline, or as part of a longevity-focused bioregulator stack.
Side Effects & Safety
Generally well-tolerated in published trials; injection site reactions. As a tissue-extract complex rather than a single synthetic peptide, sourcing consistency is a bigger practical concern than with defined analogs.
Regulatory Status
Gray AreaNot on the 503A bulks list — a polypeptide complex extracted from calf thymus, not a single defined molecule. Approved as a pharmaceutical (Thymalinum) in Russia; educational reference only in the US. Distinct from Thymosin Alpha-1/Zadaxin.
Evidence & Citations
Frequently asked
What is Thymalin?+
Thymalin (Thymus Peptide Bioregulator Complex) is a peptide studied for immune restoration and t-cell function. A standardized polypeptide fraction isolated from calf thymus. Stimulates T-lymphocyte differentiation and maturation, helps normalize the CD4:CD8 ratio, enhances phagocytic activity, and supports cytokine regulation — effects attributed to short regulatory peptides acting on gene expression in thymic and immune tissue.
What is the dosing protocol for Thymalin?+
Literature commonly references 5 mg/day (low) to 10 mg/day (maintenance) via IM / SubQ, on a 10-day course, repeated 1–2x/year cycle. Educational reference only — a licensed Stackhaus Health provider sets any personalized protocol.
What is the regulatory status of Thymalin?+
Not on the 503A bulks list — a polypeptide complex extracted from calf thymus, not a single defined molecule. Approved as a pharmaceutical (Thymalinum) in Russia; educational reference only in the US. Distinct from Thymosin Alpha-1/Zadaxin.
Where can I access Thymalin?+
Research-grade Thymalin is available through Stackhaus Research. For a personalized, provider-reviewed protocol, consult a licensed clinician through Stackhaus Health.