TB-500 / Thymosin Beta-4 Fragment

TB-500 is a synthetic version of the active region of thymosin beta-4 (TB4), a 43-amino acid protein found in virtually all human cells. The fragment contains the actin-binding domain responsible for many of TB4's regenerative effects on wound healing, tissue repair, and cellular migration.

PubMed results: 1 · Human studies: 1 · Animal studies: 1

Ranges reflect protocols studied in published research and animal-model extrapolation. Presented for research purposes only, not a recommendation or instruction for human use.

No established human dosing

• Subcutaneous Injection — standard range 2-5 mg, Twice weekly

Unknown in humans (low confidence)

• Tissue repair and wound healing research (Strong preclinical): As a synthetic fragment of thymosin beta-4 containing the actin-binding domain, TB-500 has been studied in animal models for effects on wound healing, cell migration, and tissue repair processes.
• Actin regulation and cellular migration (Strong preclinical): Research on thymosin beta-4 and related fragments demonstrates roles in actin sequestration and cytoskeletal dynamics that influence endothelial and epithelial cell migration during tissue remodeling.
• Cardiovascular and endothelial research interest (Limited): Investigational work has explored thymosin beta-4 pathway activity in atherosclerotic and endothelial dysfunction contexts, though human clinical evidence for the TB-500 fragment specifically remains limited.

• Injection site reactions — Mild, Anecdotal. Human published adverse-event data for TB-500 are sparse; injection site discomfort is the most commonly described anecdotal local effect in research-use contexts.
• Limited documented systemic adverse effects — Mild, Not established. No robust human clinical safety database establishes frequency of systemic side effects; most evidence remains preclinical or anecdotal.

• Active cancer (Theoretical / Preclinical): Pro-angiogenic and tissue-regenerative properties of thymosin beta-4 pathway activity raise theoretical concern about supporting tumor vascularization or growth.
• Pregnancy and lactation (research caution) (Theoretical / Preclinical): Reproductive safety data for TB-500 are lacking; investigational peptide protocols standardly exclude pregnant and lactating populations.

Lyophilized (powder): Refrigerated (2-8°C), Up to 24 months. Light sensitive: yes, store dark

Reconstituted (solution): Refrigerated (2-8°C), 4-6 weeks. Solvent: Bacteriostatic water

• NCT07487363 — TB-500 (Thymosin Beta 4 17-23 Fragment) for Cardiovascular Biomarkers in Stable ASCVD (PHASE1 / PHASE2), status: RECRUITING. Indications: Atherosclerotic Cardiovascular Diseases, Endothelial Dysfunction