Direct Answer
TB-500 refers to a synthetic peptide related to thymosin beta-4 (Tβ4), a naturally occurring regenerative peptide. Most published evidence concerns Tβ4 in preclinical (cell and animal) models of tissue repair. TB-500 is sold as a research chemical and is not approved for human use. As of June 2026 it sits in a regulatory gray zone: thymosin beta-4 / TB-500 was removed from the FDA 503A Category 2 bulk-substances list in April 2026 but not added to Category 1, and it remains not FDA-approved; it is under FDA PCAC review (July 2026).
Summary Table
Evidence Level
High
Key Information
Classification
Key Takeaways
- TB-500 is based on thymosin beta-4, studied mainly in cell and animal models
- Human evidence is early and limited
- TB-500 is a research chemical not approved for human use
Scientific Overview
In Plain English
TB-500 is a lab-made peptide based on thymosin beta-4, a protein the body produces that is involved in tissue repair. The science is mostly from cell and animal studies; some early human research exists for thymosin beta-4 in specific conditions. TB-500 itself is not an approved medicine.
Scientific Details
Thymosin beta-4 is an actin-binding peptide studied in models of wound healing, cardiac repair, and neural regeneration. Review literature summarizes effects on cell migration and angiogenesis observed mainly in vitro and in animals. Controlled human outcome data are limited, and research-grade TB-500 differs from the Tβ4 preparations used in earlier clinical research.
How It Works
Research describes thymosin beta-4 in relation to actin regulation, cell migration, and angiogenic signaling. These mechanisms are characterized primarily in laboratory and animal studies.
Mechanism of Action
Actin regulation
cell
Thymosin beta-4 is an actin-binding peptide; research describes it in relation to cell migration during tissue repair.
Angiogenesis
animal
Animal studies associate thymosin beta-4 with new blood-vessel formation in injury models.
Evidence Level
Human Evidence
Review literature describes thymosin beta-4 as providing a foundation for ongoing and projected clinical development; specific human-outcome data remain limited, and data for research-grade TB-500 are lacking.
Animal Evidence
Animal models address cardiac, dermal, corneal, and neural repair.
Cell Evidence
In vitro work describes actin binding and cell-migration effects.
Limitations
Much of the evidence is preclinical; the relationship between research-grade TB-500 and clinically studied Tβ4 is not well characterized in human studies.
References
- Thymosin β4: a multi-functional regenerative peptide. Basic properties and clinical applications. Expert Opinion on Biological Therapy.Reviewdoi:10.1517/14712598.2012.634793 →
- Animal studies with thymosin beta, a multifunctional tissue repair and regeneration peptide. Annals of the New York Academy of Sciences.Animal Studydoi:10.1111/j.1749-6632.2010.05479.x →
- Thymosin beta-4 denotes new directions towards developing prosperous anti-aging regenerative therapies. International Immunopharmacology.Reviewdoi:10.1016/j.intimp.2023.109741 →
Alternative Names
- TB-500
- Thymosin Beta-4
- Tetradecapeptide TB-500
- TB4
Claim Boundaries
ION BLUE is an educational research aggregator. This content summarizes published scientific literature. It is not medically reviewed, is not medical advice, and is not a recommendation to use any substance. Several peptides discussed are research chemicals not approved for human use. Consult a licensed healthcare provider. This entry does not assert that TB-500 is safe or beneficial in humans and is not a recommendation to use it.
This page summarizes published research and is for informational purposes only; it is not medical advice.