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| Primary information |
|---|
| ID | 10558 |
| Therapeutic ID | Th1110 |
| Protein Name | Thymalfasin |
| Sequence | >Th1110_Thymalfasin
SDAAVDTSSEITTKDLKEKKEVVEEAEN
|
| Molecular Weight | 3108.276 |
| Chemical Formula | C129H215N33O55 |
| Isoelectric Point | NA |
| Hydrophobicity | NA |
| Melting point | NA |
| Half-life | Approx. 2 hrs |
| Description | Chemically synthesized version identicle to human acetylated polypeptide , thymosin alpha 1. It is now approved in 35 developing countries for the treatment of Hepatitis B and C and in boosting immunity against other diseases. |
| Indication/Disease | Indicated as an adjuvant for influenza vaccine in elderly patients and as an adjuvant for both influenza and hepatitis B vaccines in chronic hemodialysis patients who failed to achieve adequate antibody titers from previous immunization. |
| Pharmacodynamics | Thymalfasin is a 28-amino acid polypeptide produced synthetically but originally isolated from thymosin fraction 5, a bovine thymus extract containing a number of immunologically active peptides. In vitro studies have shown that Thymalfasin can influence T-cell production and maturation, stimulate production of Th1 cytokines such as interferon-gamma and interleukin-2, and activate natural killer cell-mediated cytotoxicity. |
| Mechanism of Action | The mechanism of action of thymalfasin is not completely understood but is thought to be related to its immunomodulating activities, centered primarily around augmentation of T-cell function. In various in vitro assays, thymosin alpha 1 has been shown to promote T-cell differentiation and maturation; for example, CD4+, CD8+, and CD3+ cells have all been shown to be increased. Thymosin alpha 1 has also been shown to increase production of IFN-g, IL-2, IL-3, and expression of IL-2 receptor following activation by mitogens or antigens, increase NK cell activity, increase production of migratory inhibitory factor (MIF), and increase antibody response to T-cell dependent antigens. Thymosin alpha 1 has also been shown to antagonize dexamethasone-induced apoptosis of thymocytes in vitro. In vivo administration of thymosin alpha 1 to animals immunosuppressed by chemotherapy, tumor burden, or irradiation showed that thymosin alpha 1 protects against cytotoxic damage to bone marrow, tumor progression and opportunistic infections, thereby increasing survival time and number of survivors. Many of the in vitro and in vivo effects of thymosin alpha 1 have been interpreted as influences on either differentiation of pluripotent stem cells to thymocytes or activation of thymocytes into activated T-cells. Thymalfasin also has been shown in vitro to upregulate expression of toll like receptors (TLR) including TLR2 and TLR9 in mouse and human dendritic cells, as well as activate NF-kB and JNK/P38/AP1 pathways. Thymalfasin's activation of dendritic cells provides another possible pathway explaining thymalfasin's immunomodulatory and antiviral effects. |
| Toxicity | There are no reported instances of deliberate or accidental overdosage in humans. Animal toxicology studies have shown no adverse reactions in single doses up to 20 mg/kg and in repeated doses up to 6 mg/kg/day for 13 weeks, which were the highest doses studied. The highest single dose tested in animals represents 800-times the clinical dose. |
| Metabolism | NA |
| Absorption | Rapidly absorbed with peak serum levels achieved at approximately 2 hours. |
| NA |
| Clearance | NA |
| Categories | Adjuvants, Immunologic,Amino Acids, Peptides, and Proteins,Antineoplastic Agents,Hormones,Hormones, Hormone Substitutes, and Hormone Antagonists,Immunologic Factors,Peptide Hormones,Peptides,Proteins,Thymus Hormones |
| Patents Number | NA |
| Date of Issue | NA |
| Date of Expiry | NA |
| Drug Interaction | NA |
| Target | NA |
| Brand Name | Zadaxin |
| Company | SciClone Pharmaceuticals (SCLN) |
| Brand Description | SciClone Pharmaceuticals (SCLN) |
| Prescribed For | ZADAXIN thymosin alpha 1 (thymalfasin) is indicated as a monotherapy or combination therapy with interferon for the treatment of chronic hepatitis B. |
| Chemical Name | NA |
| Formulation | lyophilized preparation contains 1.6 mg thymosin alpha 1, 50 mg mannitol, and sodium phosphate buffer to adjust the pH to 6.8 |
| Physical Appearance | N. A. |
| Route of Administration | Subcutaneous |
| Recommended Dosage | The recommend-ed dose of ZADAXIN (thymalfasin) for chronic hepatitis B when used as a monotherapy or in combination with interferon (at the labeled dose and schedule for interferon) is 1.6 mg (900 µg/m2) administered subcutaneously twice a week for 6 to 12 months. Patients weighing less than 40 kg should receive a ZADAXIN (thymalfasin) dose of 40 µg/kg. |
| Contraindication | ZADAXIN (thymalfasin) is contraindicated in patients with a history of hypersensitivity to thymosin alpha 1 or any component of the injection. Because ZADAXIN (thymalfasin) therapy appears to work by enhancing the immune system, it should be considered contraindicated in patients who are being deliberately immunosuppressed, such as organ transplant patients, unless the potential benefits of the therapy clearly outweigh the potential risks. |
| Side Effects | Adverse experiences have been infrequent and mild, consisting primarily of local discomfort at the injection site, and rare instances of erythema, transient muscle atrophy, polyarthralgia combined with hand edema, and rash. |
| Useful Link 1 | Link |
| Useful Link 2 | NA |
| Remarks | NA |