What Is Thymosin Alpha-1? Immune Peptide Research Guide

An overview of Thymosin Alpha-1 — an immune-modulating peptide — covering how it is studied in immunology research, its approved use elsewhere, and its research-use-only status in the UK.

7 min read · Published 2026-06-23

What Is Thymosin Alpha-1?

Thymosin Alpha-1 (Tα1, also called thymalfasin) is a 28-amino-acid peptide derived from prothymosin alpha and originally isolated from the thymus. It is studied as an immune-modulating peptide.

Research use only. This material is supplied for in-vitro laboratory research. It is not a medicine and is not for human or veterinary consumption, administration, or therapeutic use.

How Thymosin Alpha-1 Is Studied to Work

In research Tα1 is associated with modulation of T-cell function, dendritic-cell activity and other components of immune signalling. It has been studied as an immune adjuvant and in models of infection and immune dysfunction.

Evidence & Regulatory Status

Thymosin Alpha-1 is approved as a medicine (thymalfasin) in a number of countries for specific indications such as certain viral hepatitis and as an immune adjuvant; it does not hold a UK marketing authorisation for general use. Research-grade Tα1 is supplied for laboratory research only.

Research Handling & Quality

As a lyophilised (freeze-dried) peptide it is typically stored frozen and reconstituted with bacteriostatic water for in-vitro work — see our reconstitution guide and storage guide. Identity and purity should be verified against a batch-matched Certificate of Analysis (COA) with HPLC and mass-spectrometry data. View thymosin-alpha-1 product details and COA.

Frequently Asked Questions

Is Thymosin Alpha-1 approved in the UK?

It is approved as thymalfasin in some countries for specific indications, but has no UK marketing authorisation for general use. Research-grade material is for laboratory use only.

What is Thymosin Alpha-1 studied for?

It is examined for immune-modulating effects, including T-cell and dendritic-cell function, in research models.

How is Thymosin Alpha-1 stored?

As a lyophilised peptide it is kept frozen and reconstituted with bacteriostatic water for research. See our storage and reconstitution guides.

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