Research peptides
Thymosin alpha-1
Thymosin alpha-1 is a peptide of 28 amino acids that researchers first isolated from thymus tissue. The synthetic version carries the generic name thymalfasin.
- Container
- Glass vial, crimp seal, flip-top cap
- Storage
- -20 °C, desiccated
- Paperwork
- Lot certificate (HPLC + mass spec) shown before you pay
Lot certificates
You’ll see American Peptides on the lab’s copy. They’re our supplier.
- 10 mg, lot TA110-0803: 99.78% purity (RP-HPLC), 10.87 mg measured, identity confirmed by mass spec. Issued 2026-08-28 by Bioviridian Inc.. Verify certificate COA7585
Our vials are filled from lots made by our supplier, American Peptides, and tested by Bioviridian Inc.The laboratory’s original certificate lists American Peptides as the vendor. Look up the code at bioviridians.com to check it.
What researchers study it for
- Chronic hepatitis B and hepatitis C
- Sepsis
- Immune responses after vaccination
- Add-on treatment in cancer research
- How dendritic cells and T cells behave
How it is thought to work
The peptide is characterized as an immune modulator touching several kinds of immune cells. According to reviews, it engages Toll-like receptors on myeloid and plasmacytoid dendritic cells, which then produce cytokines. In mice it pushed dendritic cells toward maturity and supported T-helper 1 responses against fungi. Note that some of these reviews were written by employees of the company that makes it.
Where the research stands
Approved as thymalfasin in some countries; nothing approved in the US. By one review's count, thymalfasin holds marketing authorization in over 35 countries for hepatitis B and hepatitis C. In the United States, Drugs@FDA shows nothing approved, and the FDA includes it on its compounding list of substances whose safety is not settled. A large phase 3 study in sepsis (1,106 adults) did not demonstrate that it lowers deaths.
Sources
- Dominari A, et al. (2020). Thymosin alpha 1: A comprehensive review of the literature. World Journal of Virology.
- Romani L, et al. (2004). Thymosin alpha 1 activates dendritic cells for antifungal Th1 resistance through toll-like receptor signaling. Blood.
- Wu J, et al. (2025). The efficacy and safety of thymosin α1 for sepsis (TESTS): multicentre, double blinded, randomised, placebo controlled, phase 3 trial. BMJ.
- King R, Tuthill C. (2016). Immune Modulation with Thymosin Alpha 1 Treatment. Vitamins and Hormones.
For laboratory research use only. Not a drug, food, supplement or cosmetic; not for human or veterinary use. Nothing on this page is medical advice or a usage guide.