TB-500
Also known as: Thymosin beta-4 fragment, TB4 fragment
A synthetic peptide related to the naturally occurring protein thymosin beta-4; studied in animal and laboratory research and not approved for humans.
This page is informational and scientific in nature. It is not medical advice and not a set of instructions for use. Consult a physician for health questions.
Key facts
- Substance class
- Synthetic peptide related to thymosin beta-4
- Research stage
- Predominantly preclinical research
- Regulatory status
- Not approved — not a medicine; not approved by the EMA, FDA or CBG
- Category
- Repair & tissue, Experimental research
What it is
TB-500 is a synthetic peptide related to thymosin beta-4, a naturally occurring protein found in nearly all human cells. In trade and in research, "TB-500" usually refers to a fragment or variant of that protein rather than the complete molecule. That distinction matters: properties of thymosin beta-4 cannot simply be attributed to TB-500.
Mechanism of action
Thymosin beta-4 has been described in research in connection with processes around cell movement and tissue organisation. To what extent a fragment such as TB-500 reproduces that behaviour has not been established. There is no generally accepted, detailed mechanism of action for TB-500 as a separate substance.
Research status
Research into TB-500 and thymosin beta-4 takes place largely in laboratory and animal studies. Sound clinical evidence in humans is absent. Statements about efficacy or safety in humans are therefore not scientifically supported.
Regulatory status
TB-500 is not approved by the EMA, the FDA or the CBG and is not a registered medicine. In sport, thymosin beta-4-type substances additionally appear on the prohibited list of the World Anti-Doping Agency (WADA).
What remains unknown
Mechanism of action, pharmacokinetics and safety in humans are largely unknown. The relationship between what a label states and what grey-market material actually contains is equally uncertain — see Quality & provenance.
Terms used on this page
Sources
Last updated: 2026-07-31
To repeat the essentials: this information is not medical advice and not a set of instructions for use. Research peptides that are not approved are not medicines; their safety outside controlled research has not been established.