Thymosin Beta-4 fragment (TB4-derived) · Evidence-based safety and harm-reduction overview.
| Also known as | Thymosin Beta-4 fragment (TB4-derived) |
| Category | Peptide |
| Class | Synthetic thymosin derivative (43-amino-acid peptide) |
| Route in research | Intravenous, intramuscular, or subcutaneous injection in animal models |
| Half-life | Unknown in humans; estimated hours in animal studies |
| US legal status | Not FDA-approved for human use. Banned in sport by WADA. Sold as a research chemical only. |
TB-500 is a synthetic peptide comprising the first 43 amino acids of Thymosin Beta-4, a naturally occurring protein involved in immune function and cell migration. It is marketed as a research compound derived from, but not identical to, the full Thymosin Beta-4 molecule. The truncated form has different pharmacokinetic properties than the native protein.
TB-500 is proposed to promote cell migration and actin polymerization, a process essential for cell motility and tissue remodeling. It may also stimulate angiogenesis (new blood-vessel formation) and upregulate anti-inflammatory pathways. The precise human receptors and signaling cascades remain incompletely characterized; most data come from cell culture and rodent studies.
Thymosin Beta-4 was first identified as a major immunoactive peptide in the thymus gland in the 1970s. TB-500, a truncated synthetic derivative, emerged in research in the 1990s as a potential therapeutic for tissue repair. It entered early-stage clinical trials for certain wound-healing indications but did not advance to FDA approval. The compound became popular in sports and biohacking communities despite the absence of human efficacy data.
Animal and in-vitro studies suggest roles in cell migration, blood-vessel formation, and wound healing. Research in mice, rats, and other models reports accelerated recovery from muscle and tendon injury. Human clinical efficacy evidence is minimal; no large randomized controlled trials in humans exist.
In animal studies, TB-500 has been administered intravenously, intramuscularly, or subcutaneously at doses of approximately 2-10 milligrams per kilogram per day over days or weeks. Some human case reports describe much lower doses, though these are not part of any approved clinical protocol.
This is general research/context information, not medical advice or a recommended protocol.
Anecdotal reports describe combining TB-500 with BPC-157, ipamorelin, or other recovery-focused compounds. No clinical evidence supports the safety or efficacy of such combinations.
If you are going to research a compound, verifying identity and purity is the single most protective step. Independent analytical testing and sterile-handling supplies reduce risk.
Compare testing optionsIt is related but not identical; TB-500 refers to a synthetic fragment/version sold for research.
No. It is on the WADA Prohibited List.
There is no robust clinical evidence. Animal studies are promising, but human trials have not established efficacy.
Thymosin Beta-4 has immunomodulatory roles, but TB-500's effects on human immune function are not well characterized.
Medical & legal disclaimer. This site is for informational and harm-reduction purposes only. It is not medical advice and is not a substitute for a licensed healthcare professional. The compounds discussed are largely not approved by the FDA for human use and many are sold strictly as research chemicals 'not for human consumption.' Nothing here is an endorsement to purchase, possess, or use any substance. Laws vary by jurisdiction. Always consult a qualified physician and follow the law where you live.
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