TB-500
TB-500 is a synthetic fragment related to thymosin beta-4, a natural protein involved in tissue repair. It has not been tested in human trials and is not approved for any use.
What it is
A short peptide marketed as a version of thymosin beta-4. The full protein has been studied in a few human trials, but TB-500 itself has not.
What the evidence shows
In people
None for TB-500 itself. Small trials of thymosin beta-4 products (for example eye drops) do not apply to injected TB-500.
In animals and labs
Animal studies of thymosin beta-4 suggest roles in wound healing and blood vessel growth.
Legal status
Not FDA-approved. Prohibited in sport by WADA and has been found in doping cases in racing and athletics.
Dosing
There is no established human dose
No regulator has approved a dose for human use. Numbers shared online come from animal studies, small early trials, or seller protocols, and none of them have been shown to be safe or effective. BOTH does not publish dosing, mixing, or injection instructions for unapproved compounds.
Known risks
- No human safety data
- Theoretical concern about effects on tumor growth
- Contamination and mislabeling in research-grade products