Thymosin Beta-4
Also known as: TB4, TB-4, beta-thymosin
By GLPeptideSciences Editorial Team · How we evaluate evidence · Reviewed by Dr. George S. Watson, MD, Cardiothoracic Surgeon · Updated 2026-06-02
A naturally occurring peptide central to cell migration and tissue repair — the parent molecule of the commonly discussed fragment TB-500.
What it is & how it works
What it is
Thymosin Beta-4 is a naturally occurring peptide central to cell migration and tissue repair. It’s the parent molecule of TB-500, the fragment usually sold on the research market.
How it is thought to work
It regulates actin, a building block of the cytoskeleton, supporting the cell movement involved in wound healing — alongside anti-inflammatory and angiogenic effects in models.
The evidence and the caveat
The basic biology and animal data are solid, and there’s been some early clinical interest, but human outcome data is limited and it isn’t approved. Recovery claims should be read cautiously.
What it's discussed & studied for
- Tissue repair and wound healing (preclinical/limited)
- Anti-inflammatory and recovery discussion
Discussion of a use is not a claim that it works or is approved.
Research status
An endogenous peptide with real preclinical interest and some early clinical work; not approved for general use. The research-market 'TB-500' is a related fragment.
Evidence quality
Solid basic biology and animal data, limited human trial outcomes. Read recovery claims cautiously.
Dosing discussion
No approved label or validated human protocol; community use is extrapolated from animal work and the TB-500 fragment.
Educational summary of what is discussed in the literature and community — not a dosing recommendation or medical advice.
Safety & harm reduction
Human safety as an administered compound is not well characterized; preclinical tolerability does not establish human safety.
Sourcing literacy
No approved product; research-market material (often sold as TB-500) is unverified.
Selected literature
FAQ
What's the difference between Thymosin Beta-4 and TB-500?
Thymosin Beta-4 is the full natural peptide; TB-500 is a synthetic fragment of it that's commonly sold on the research market. They're related but not identical.