Full 43-amino-acid thymosin beta-4 molecule (parent compound; tb500 is the active fragment). Studied for cardiac repair, wound healing, hair follicle stimulation, and anti-inflammatory signaling. Different pharmacology from tb500 fragment.
Short plasma half-life; tissue-level biological effects sustained
SKUs
2
Evidence
Moderate Evidence
Thymosin Beta-4 (TB4) is the full-length, naturally occurring 43-amino-acid protein found in virtually every type of cell in the human body. It is one of the most abundant proteins inside cells and plays essential roles in regulating actin dynamics, wound healing, anti-inflammatory responses, and cardiac regeneration. TB-500 is a synthetic peptide corresponding to the active region of TB4, but the full-length protein has additional properties and a somewhat different research profile.
Cardiac Regeneration Research
Full-length Thymosin Beta-4 has been studied extensively for cardiac regeneration. It activates dormant epicardial progenitor cells — stem-like cells on the heart's surface — and can stimulate the formation of new cardiac muscle cells after injury in animal models. This is one of the most clinically exciting areas of TB4 research.
Wound Healing
Full-length TB4 promotes wound healing through multiple mechanisms: promoting the migration of skin cells, fibroblasts, and endothelial cells into the wound; reducing inflammation; and stimulating collagen synthesis. Clinical studies with eye drops containing TB4 have been conducted for dry eye and corneal wound healing.
Neurological Recovery
Research has examined TB4 for neurological recovery, showing it promotes remyelination in models of multiple sclerosis and reduces damage in models of traumatic brain and spinal cord injury through mechanisms including anti-inflammatory and stem cell activation effects.
Dry Eye Disease Research
Thymosin Beta-4 eye drops (RGN-259) have completed clinical trials for dry eye disease and neurotrophic keratopathy. Phase 3 trials showed improvements in dry eye symptoms and corneal repair, making this one of the closest TB4 applications to potential regulatory approval.
Cardiac regeneration in animal models through epicardial progenitor cell activation.
Wound healing acceleration including corneal wound repair in clinical trials.
Neurological protection and remyelination in animal models.
Phase 3 dry eye trials completed with positive results.
TB4 is the parent compound of TB-500, which contains its active region.
Full-length TB4 has more complex biology than TB-500 but also a more difficult production profile. Most human clinical data are in the dry eye/corneal application. The cardiac regeneration findings in animals have not yet been translated into approved human therapies. Not FDA-approved for systemic use. The full protein requires careful handling and storage.
Every cell in your body contains a dynamic scaffold made of actin protein that gives the cell its shape and allows it to move. Thymosin Beta-4 is the molecule that sequesters actin monomers — the building blocks of this scaffold — controlling when and where the scaffold assembles. When a wound occurs, TB4 is released in large amounts and directs a coordinated response: it helps repair cells migrate toward the wound, signals new blood vessels to grow into the repair area, and tells the body to keep inflammation in check rather than going overboard. In the heart specifically, TB4 appears to awaken progenitor cells on the heart's surface that normally lie dormant, potentially activating them to produce new heart muscle tissue after injury.
Full-length Thymosin Beta-4 has been well-tolerated in clinical trials, including the eye drop trials. No significant systemic safety concerns have been identified. Not FDA-approved for systemic indications. Pharmaceutical-grade production is complex and important for ensuring safety of injectable forms.
Moderate Evidence
This compound has been studied in Phase 1 or Phase 2 human trials. Evidence is encouraging but more large-scale trials are needed.
Published Research Ranges
1.5–6mg per dose, varying frequency in tissue repair contexts
Research Context Only: These are ranges reported in published scientific studies for educational reference. They are not dosing recommendations. This is not medical advice. Always consult a qualified healthcare professional.
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Thymosin Beta-4 Induces Epicardial Progenitor Cell Migration into the Myocardium
Research Education Only: This profile is for educational purposes only. All information is sourced from published scientific literature. This is not medical advice. Not for human consumption. Consult qualified medical professionals for any health decisions.
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