TB-500
Pending PCACAlso known as: Thymosin Beta-4 Fragment, TB4-Frag
Healing & RecoveryLast reviewed: April 28, 2026
A synthetic fragment of thymosin beta-4, a naturally occurring peptide involved in tissue repair and regeneration. Widely used in the biohacking community for injury recovery.
Mechanism of Action
Promotes cell migration, blood vessel formation, and reduces inflammation. Upregulates actin, a cell-building protein critical for healing and cell migration to injury sites.
Common Uses
- Muscle and tendon repair
- Wound healing
- Reducing inflammation
- Hair regrowth (emerging research)
- Cardiac tissue repair
Known Risks
- Limited human clinical data
- Potential tumor growth concerns (theoretical)
- Injection site reactions
- Headaches reported anecdotally
Regulatory Status
On April 15, 2026, the FDA announced TB-500 will be removed from the Category 2 'significant safety risks' list effective April 22, 2026. Scheduled for PCAC review on July 23, 2026 to determine eligibility for the 503A bulk drug substances list. Compounding pharmacies should exercise caution until PCAC takes action.
Get notified when the PCAC decides on TB-500
Scheduled review: July 23, 2026. We'll email you the same day results are announced.
Common Protocols
Protocol information is for educational reference only. Dosing varies significantly by individual, condition, and physician guidance. Always work with a licensed healthcare provider.
Subcutaneous injection
Typical Dose
5–20 mg per week (loading), 2–5 mg per week (maintenance)
Frequency
2–3x per week
Cycle Length
4–6 weeks loading, then maintenance as needed
Often stacked with BPC-157. Higher loading doses used for acute injuries. Reconstitute with bacteriostatic water.
Related Compounds
Research References
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This information is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy. Data is compiled from published research and regulatory sources and may not reflect the most recent developments.