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Healing & Recovery
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TB-500 (Thymosin Beta-4): Soft Tissue Repair & Flexibility

TB-500 mimics the active region of Thymosin Beta-4, a naturally occurring repair protein. It's the long-loading counterpart to BPC-157.

TB-500 is a synthetic fragment of Thymosin Beta-4, a 43-amino-acid protein present in almost every cell of the body. The synthetic version contains the actin-binding region that drives cell migration to injured tissue, which is why researchers pair it with BPC-157 for serious soft-tissue work.

What TB-500 Does

TB-500 promotes actin polymerization, which underpins how cells move into wounded areas. It also upregulates VEGF, modulates inflammation, and appears to improve flexibility — likely via fascial hydration. Veterinary use in racehorses is widespread for this reason.

Dosing Protocols

Most protocols load with 2,000–2,500 mcg twice weekly for 4–6 weeks, then drop to a 1x weekly maintenance dose. TB-500 has a long half-life relative to BPC-157, so daily injections are unnecessary. Subcutaneous administration is standard.

Stacking with BPC-157

The BPC-157 + TB-500 stack is the most common combination in tendon and ligament recovery protocols. BPC-157 drives local angiogenesis and growth factor signaling; TB-500 drives systemic cell migration and flexibility. The two are complementary, not redundant.

Reference page

Reconstitution chart, dose calculator, and storage notes for this peptide.

Open the reference card

FAQ

Is TB-500 the same as Thymosin Beta-4?
No. TB-500 is a shorter synthetic fragment containing the active actin-binding region. It is cheaper to produce and easier to dose, but not identical to the full TB-4 protein.

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