What is Thymosin Alpha 1?


Thymosin alpha 1 (Tα1) is a powerful modulator of immunity and inflammation. Thymosin is a peptide, or small protein, produced naturally by the thymus gland. It is one of several polypeptide hormones secreted by the thymus that controls the maturation of T-cells, which actively participates in the immune response. The thymus is a critical part of your immune system, where individual T-cells are tailored to respond to the millions of bacteria, fungi, or viruses that could invade your body. It is most often given for chronic viral diseases but has also been shown to increase innate immunity factors and help fight against harmful autoimmune processes. It is given to help control inflammation associated with chronic diseases, which can cause excess fatigue.

This peptide has been approved by the FDA for treatment of malignant melanoma, Hepatitis B and C, and influenza. It is being further studied for antiviral properties, cancer treatments, as a powerful antioxidant, to supplement treatments for tick-borne infections, and immune modulation and boosting. It is indicated as adjuvant therapy for support of immune systems suppressed by chemotherapy. Thymosin alpha 1 has been approved for use in 30 countries for the treatment of Hepatitis and cancer. Ta1 is marketed worldwide as Zadaxin™ (thymalfasin, SciClone Pharmaceuticals, China). It has been used to support immunity in over 3,000 patients and in over 70 clinical studies, either as monotherapy or in conjunction with current allopathic medicines. Zadaxin is currently in Phase III trials for the treatment of hepatitis C and in Phase II trials for hepatitis B in the United States.

How does it work?

Specifically, Tα1 has been shown to enhance the function of certain immune cells called T and dendritic cells. This is very important to anyone with a depressed immune system or suffering from an infection, as these white blood cells play pivotal roles in the body’s defense process. T-cells come in two forms: killer and helper cells. Killer T-cells are responsible for hunting down and destroying our body’s own cells that are cancerous or infected with bacteria or viruses. Tα1 is thought to modulate the immune system by augmenting T-cell function. Tα1 may affect thymocytes by stimulating their differentiation or by converting them to active T-cells.

Dendritic cells are just as valuable to our body’s defense system. These cells gather important information about infection or the presence of cancerous cells, and communicate with the T cells, who then act appropriately to eradicate the unhealthy cells and stop the infection or cancer growth.

Tα1 itself has been shown to exhibit antibacterial and antifungal properties, suppress tumor growth, increase vaccine effectiveness, and protect against oxidative damage. The proposed mechanism of action involves restoration of immune function and modulation by augmenting T cell function and supporting the conversion of thymocytes to active T cells.

Infection and Tα1

Studies have shown that individuals fighting infection have a lower amount of circulating Tα1 and suppressed helper T cell numbers compared to healthy individuals. This is problematic, as optimal immune function is vital to recovery from infection. Supplementation with Tα1 has the potential for great therapeutic benefit for patients suffering from infection or autoimmune disease.

In addition to its use in the treatment of Hepatitis, AIDS, and cancer, Tα1 has shown great promise in the treatment of Lyme disease. This is unsurprising when one considers the large role the immune system plays in combating the disease. Tα1 assists the immune system in the location and eradication of the Lyme bacteria and infected cells, while helping to prevent oxidative damage, thereby decreasing inflammation and enabling better quality of life throughout treatment.

Possible Side Effects

Thymosin Alpha 1 appears to be quite well tolerated. No adverse drug interactions have been observed. No side effects, other than some irritation or burning sensation at the site of injection, have been seen.

Benefits of Thymosin Alpha 1

  • Exhibits antibacterial and antifungal properties
  • Increases vaccine effectiveness
  • Suppresses tumor growth
  • Enhances the function of certain immune cells
  • Helps eradicate the unhealthy cells and stop infection or cancer growth
  • Strengthens your immune system

Thymosin Alpha 1 is used for clinical conditions where immune support is necessary:

  • Conditions requiring immune response modulation
  • Hepatitis B & C
  • Cancer – non-small cell lung (NSCLC), hepatocellular, malignant melanoma
  • Chemotherapy adjunct
  • Chronic inflammatory conditions
  • Autoimmunity
  • Cystic fibrosis
  • Lyme disease
  • Blocks steroid-induced apoptosis of thymocytes
  • Depressed response to vaccinations; adjunct to flu vaccine
  • Geriatric immune support
  • DiGeorge’s syndrome
  • May reduce hematological toxicity of cytotoxic drug therapies



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