TB-500 is the most common research-grade name for a synthetic version of thymosin beta-4 fragment, a peptide that binds actin and regulates cell migration, angiogenesis, and tissue repair. Most peptide vendors sell either the full thymosin-beta-4 peptide or shorter fragments (1-4 or 17-23). Published research is preclinical; there is no FDA-approved TB-500 product.
Research notes
How does TB-500 work?
TB-500 is a synthetic peptide based on a fragment of thymosin beta-4, a naturally occurring 43-amino-acid protein involved in actin regulation, cell migration, and tissue repair. Preclinical research focuses on its role in cell migration to injury sites and angiogenesis.
What doses are used in research?
Twice-weekly injection at 2–5 mg per dose is the most commonly cited research protocol. Loading-phase variants front-load higher doses for the first 4–6 weeks.
Audit focus
For TB-500, the variance between vendors is mostly on identity confirmation rather than purity. We've seen multiple grey-market batches that were under-strength rather than off-spec; mass-spec identity tests catch these.
What it's researched for
- recovery
- tissue repair
Where to source it
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Frequently asked about TB-500
What is TB-500?
TB-500 is the research-grade name for a synthetic version of thymosin beta-4 (or one of its active fragments). Thymosin beta-4 is a 43-amino-acid peptide that binds actin and is involved in cell migration, angiogenesis, and tissue-repair processes. The peptide-vendor product line sometimes includes the full molecule and sometimes just the active fragment.
How does TB-500 work?
The published mechanism centers on actin sequestration. Thymosin beta-4 binds G-actin and modulates actin-cytoskeleton dynamics, which affects cell migration during wound repair. Secondary mechanisms include angiogenesis promotion and anti-inflammatory effects, similar in framing to BPC-157 but through different molecular targets.
Is TB-500 the same as thymosin beta-4?
TB-500 is sometimes used as a synonym for thymosin beta-4, but research-peptide vendors often sell shorter active fragments (e.g., TB-500 1-4 or TB-500 17-23) under the same product name. Check the SKU description carefully — full TB-500 (43 aa) and the shorter fragments are not equivalent for cross-vendor pricing comparison.
Is TB-500 FDA-approved?
No. TB-500 (thymosin beta-4) is not FDA-approved for any human indication and is not on any country's approved-drug list. It is sold only as research-grade material. Veterinary use in racehorses is banned by every major racing authority.
What doses are used in TB-500 research?
Published research literature cites 2–10 mg weekly subcutaneous, often in loading + maintenance protocols (e.g., higher dose for 4–6 weeks, then a maintenance taper). Half-life is multi-day; most protocols use weekly or twice-weekly schedules.