Thymalfasin (Thymosin Alpha-1 Clinical)
Also known as: Zadaxin, Tα1, SCV-07
Overview
Thymalfasin is the pharmaceutical-grade, synthetic form of thymosin alpha-1 (Tα1), marketed under the brand name Zadaxin. It is approved in over 37 countries for treatment of chronic hepatitis B, chronic hepatitis C, and as an adjuvant in cancer immunotherapy. During the COVID-19 pandemic, thymalfasin was used in China and other countries with evidence of mortality reduction in severe cases. Unlike conventional immunostimulants, thymalfasin acts as an immune modulator—normalizing immune function in states of both immunodeficiency and autoimmune dysregulation.
Mechanism of Action
Thymalfasin promotes maturation and differentiation of T-lymphocytes from bone marrow precursors through thymic processing. It activates dendritic cell function, enhances natural killer cell cytotoxicity, stimulates interferon-alpha and interferon-gamma production, and upregulates MHC class I and II expression on antigen-presenting cells. In viral infections, it restores T-cell-mediated antiviral immunity that becomes exhausted or suppressed during chronic infection. IL-2 and IL-3 upregulation contribute to T-helper cell restoration.
Potential Benefits
- Approved treatment for chronic hepatitis B and C
- Adjuvant immunotherapy in cancer patients
- Restored T-cell function in immunocompromised patients
- Reduced mortality in severe COVID-19 (clinical data from China)
- Vaccine adjuvant activity
- Immune normalization in aging (immunosenescence)
Dosage Protocols
The following reflects doses used in published research studies. This is not medical advice. Consult a qualified healthcare professional.
| Beginner | 1.6 mg SC 2x weekly |
| Intermediate | 1.6 mg SC 2x weekly ongoing |
| Advanced | 1.6 mg SC 3x weekly (off-label intensive protocols) |
| Cycle Duration | 6 months (chronic hepatitis B/C) to chronic (immune support) |
Same molecule as Thymosin Alpha-1 (Thymalfasin = Zadaxin brand). FDA-approved in 30+ countries, not U.S.
Use our Reconstitution Calculator to determine exact syringe units for your protocol.
Routes of Administration
Subcutaneous Injection High
Standard clinical route. Rotate sites.
Read our full Routes of Administration Guide for detailed comparison of all delivery methods.
Stacking Protocols
Popular research stacks involving Thymalfasin (Thymosin Alpha-1 Clinical):
Hepatitis Protocol
Approved combination for chronic hepatitis B/C in some countries.
Immune Support Stack
Research combination for immunocompromised or post-infection recovery.
Explore our complete Peptide Stacking Guide for more combinations and safety considerations.
Reconstitution
| Storage | Refrigerate at 2-8°C after reconstitution. Do not freeze reconstituted solution. |
|---|
Typical vial sizes: 1.6 mg. Add bac water slowly down the side of the vial, swirl gently — do not shake. Use insulin syringe for precise dosing.
Need exact syringe measurements?
Amino Acid Sequence
Ac-Ser-Asp-Ala-Ala-Val-Asp-Thr-Ser-Ser-Glu-Ile-Thr-Thr-Lys-Asp-Leu-Lys-Glu-Lys-Lys-Glu-Val-Val-Glu-Glu-Ala-Glu-Asn-OH
Side Effects & Safety
- Generally very well tolerated
- Rare injection site reactions
- Mild flu-like symptoms
- Theoretical immune overstimulation in autoimmune conditions
Safety & Contraindications
This information is for educational purposes only. Consult a qualified healthcare provider before using any peptide.
Pregnancy / Lactation
Bleeding Disorders
Active Skin Infection at Injection Site
Drug Interactions
- Immunosuppressant Therapy:
Pharmacokinetics
| Half-Life | ~2 hours |
|---|---|
| Storage | Store lyophilized peptide at -20°C (long-term) or 2-8°C (short-term, under 30 days). Reconstituted: refrigerate at 2-8°C and use within 28-30 days. Protect from light. Do not freeze reconstituted solution. |
Synergistic Compounds
The following compounds have been studied alongside Thymalfasin (Thymosin Alpha-1 Clinical) for potential complementary or synergistic effects:
Learn More
References & Further Reading
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