Thymalfasin (Zadaxin)
Immune Modulationapproved_internationalAlso known as: Zadaxin, Thymalfasin, SciClone TA1
The pharmaceutical-grade form of Thymosin Alpha-1, FDA-approved in over 30 countries for hepatitis B/C and as an immune modulator for cancer therapy.
Overview
Thymalfasin (brand name Zadaxin) is the pharmaceutical-grade synthetic version of Thymosin Alpha-1, approved in over 30 countries for treatment of hepatitis B, hepatitis C, and as an immune adjuvant in cancer therapy. While Thymosin Alpha-1 is available from compounding pharmacies, Zadaxin represents the clinically validated, GMP-manufactured version with the most extensive human trial data.
Mechanism of Action
Thymalfasin enhances immune function through: (1) Stimulation of T-cell maturation and differentiation; (2) Enhancement of dendritic cell function; (3) Modulation of Th1/Th2 immune balance; (4) Increased NK cell activity; (5) Augmentation of antibody responses to vaccines; (6) Anti-tumor immune surveillance enhancement.
Molecular Formula
C129H215N33O55
Molecular Weight
3108.3 g/mol
Sequence
28 amino acid peptide: Ac-SDAAVDTSSEITTKDLKEKKEVVEEAEN
Dosage Protocols
Dose Range
1.6mg – 3.2mg
Frequency
Twice weekly
Route
subcutaneous
Cycle Length
6-12 months
Standard Zadaxin dosing: 1.6mg SC twice weekly. Often used in cancer immunotherapy protocols.
Source: Zadaxin prescribing information
🧮 Personalized Dosage Calculator
💰 Estimated Pricing
Typical Supply
1.6mg vials
Last Updated
2026-02
Pharmaceutical-grade Zadaxin. Compounded TA1 available cheaper.
⚠️ Prices are estimates based on publicly available data and may vary significantly by vendor, location, and prescription status. This is not medical or financial advice.
Side Effects
| Effect | Severity |
|---|---|
| mild | |
| mild |
Pros & Cons
Extensive human clinical trial data
Approved in 30+ countries
Powerful immune modulator
Well-established safety profile
Effective as vaccine adjuvant
Not FDA-approved in US
Requires injections
Can be expensive
May overstimulate immune system in autoimmune conditions
Limited US availability of pharmaceutical grade
Research Studies
🩸 Blood Work
No specific bloodwork requirements reported for this peptide. General health panels are always recommended before starting any peptide protocol.
Legal Status
Approved in 30+ countries. Not FDA-approved in the US but available through compounding pharmacies with prescription.
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