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Editorial caution Not FDA-approved. Restricted on the FDA bulk substances list. This page is an editorial overview, not medical advice or a recommendation. Many peptides have limited human-trial evidence. Always work with a licensed, board-certified clinician.

What it is

TB-500 is a synthetic fragment of Thymosin Beta-4, studied for tissue repair, wound healing, and endothelial function.

Mechanism of action

TB-500 is a synthetic version of a 17-amino-acid fragment of thymosin beta-4 (the active LKKTETQ region). Thymosin beta-4 is a naturally occurring protein involved in actin sequestration and remodeling. The peptide promotes cell migration (key to wound healing), upregulates VEGF and other pro-angiogenic factors, and modulates inflammatory cytokine signaling. The actin-binding mechanism is the dominant explanation for tissue-repair effects.

Reported uses

Evidence base

Preclinical animal models and limited human data.

Regulatory status

Not FDA-approved. Restricted on the FDA bulk substances list.

Typical dosing context

Common research and clinical-use protocols:

Dosing in research and clinical-use contexts varies. Specific protocols should always be set by a prescribing clinician, not by patient-direct sources.

Side effects and safety

Reported side effects are mild and similar to BPC-157: injection-site irritation, mild lethargy in the first week. Pre-clinical safety data is reasonable; human safety data is limited. Like BPC-157, TB-500 is on the FDA 503A bulk substances restricted list.

Common stacking protocols

The standard healing stack is BPC-157 + TB-500. Some protocols add GHK-Cu for additional tissue-repair signaling, or pair with growth-hormone secretagogues (ipamorelin/CJC-1295) for systemic recovery.

How to access TB-500

Most peptides discussed on this page are compounded products requiring a prescription from a licensed clinician. Reputable telehealth peptide programs include physician-led oversight, accredited compounding pharmacies, and clear regulatory framing. For weight-management GLP-1 programs, see our provider reviews.

Frequently asked questions

What is TB-500?

TB-500 is a synthetic fragment of Thymosin Beta-4, studied for tissue repair, wound healing, and endothelial function.

Is TB-500 FDA-approved?

Not FDA-approved. Restricted on the FDA bulk substances list.

What are the typical uses of TB-500?

Uses include: Soft-tissue healing (research), Endothelial repair (research), Anti-inflammatory effects (research). This is research and clinical-use context, not a recommendation. Always work with a licensed clinician.

What is the evidence behind TB-500?

Preclinical animal models and limited human data.

What is the typical dosing for TB-500?

Reported dosing: 2 mg subcutaneous twice weekly (research context). Actual dosing should always be determined by your prescribing clinician, not by online sources.

Is TB-500 banned in sports?

Yes. The World Anti-Doping Agency (WADA) lists thymosin beta-4 and its analogs as prohibited substances. Athletes subject to WADA testing should not use TB-500.

How is TB-500 different from thymosin alpha-1?

Thymosin beta-4 (the source of TB-500) is involved in tissue repair and cell migration. Thymosin alpha-1 (a different peptide) is involved in immune function. They are not interchangeable.

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