When recovery becomes the limiting factor.

TB-500 commonly refers to N-acetylated LKKTETQ, a seven-amino-acid fragment corresponding to residues 17–23 of thymosin beta-4. TB-500 free base and TB-500 acetate are distinct substances; the prescription label must identify which one the finished formulation contains.

The LKKTETQ sequence includes thymosin beta-4’s actin-binding region. Related laboratory and animal research has measured cell movement, blood-vessel formation, wound closure, and collagen—processes that explain the recovery interest around this peptide family.

No human TB-500 studies were identified. In one fibroblast scratch assay, 50 µg/mL TB-500 for eight hours produced no significant difference in wound closure versus vehicle. A metabolite, N-acetylated LKKTE, produced a small significant change under the same conditions.

The planned format is a 10 mg injection vial. Orders are closed. The availability update will include the exact substance, concentration, package, directions, storage, supply, price, states served, and refill timing.

If TB-500 becomes available, the prescription will be dispensed by a licensed U.S. compounding pharmacy. The patient-specific label will list the finished formulation, concentration, storage instructions, and beyond-use date.

No human exposure or clinical safety studies were identified for TB-500. Human safety data are unavailable for a TB-500 injection.

TB-500 appears in WADA’s 2026 Prohibited List under growth factors and growth-factor modulators. Tested athletes should check the rules that apply to them.