PeptideCompareThymosin Alpha-1 — the immune modulator.
Thymosin Alpha-1 (Tα1) is a 28-amino acid peptide naturally produced by the thymus gland. It is an approved drug in over 30 countries (as Zadaxin) for immune-related conditions, making it one of the better-validated peptides in this category.
What is Thymosin Alpha-1?
Thymosin Alpha-1 is a naturally occurring thymic peptide central to T-cell maturation and immune regulation. It enhances the function of immune cells (T-cells, dendritic cells, NK cells) and modulates inflammatory responses. It is approved as Zadaxin in many countries for hepatitis B/C, as a vaccine adjuvant, and as an immune support agent — though not approved in the EU or US.
What does the research show?
What to look for when buying in Europe
Among the better-validated peptides clinically. Research-grade Tα1 should be ≥98% HPLC with mass-spec confirmation. PeptideCompare tracks several EU vendors.
Molecular information
Pharmacokinetics
Potency retained over time
Each line is one storage condition: it starts at 100% and falls as potency is lost. Above the dashed 80% line the material is considered reliable — hover for exact values.
⚠ Modelled per compound from molecular structure — chain length, cyclisation, oxidation- and deamidation-prone residues and light sensitivity. Indicative only, not lab-measured per batch.
Compare Thymosin Alpha-1 across EU suppliers
7 EU vendors · COA-verified · from €30.19 · Updated monthly
References
- ETASS, a multicentre randomised controlled trial of thymosin alpha-1 in severe sepsis across six Chinese teaching hospitals, with 28-day all-cause mortality as the primary outcome. The largest single trial behind the sepsis claims. Wu J, et al. Crit Care. 2013;17(1):R8. (ETASS trial) PMC4056079
- Systematic review of 19 randomised trials. Mortality was reported in 10 of them, covering 530 patients, with a pooled risk ratio of 0.59 (95% CI 0.45–0.77). The authors themselves flag small sample sizes and weak study design as the limiting factor. Li C, et al. BMC Infect Dis. 2016;16:488. PMC5025565
- More recent meta-analysis restricted to monotherapy and excluding the COVID-19 period: 11 trials, 967 versus 960 patients, 28-day mortality odds ratio 0.73 (95% CI 0.59–0.90). A smaller effect than the 2016 review — the usual direction of travel as trial quality improves. Zhang Y, et al. Front Cell Infect Microbiol. 2025;15:1673959. PMC12440967
- Pharmacokinetics after subcutaneous injection of three formulations in healthy volunteers — the human study behind the half-life shown above, rather than a literature estimate. Rost KL, et al. Int J Clin Pharmacol Ther. 1999;37(1):51–57.