TB-500

TB-500, also known as Thymosin Beta-4 Acetate, is a synthetic fragment of thymosin beta-4, a naturally occurring peptide in the beta-thymosin family. Research interest centers on its relationship with actin, the structural protein that underpins cell movement, and on the migration of repair-associated cells. It is typically grouped with recovery-focused research compounds and is supplied for laboratory research use only.

Research describes TB-500 as binding actin monomers and influencing assembly of the cytoskeleton, the internal scaffolding cells use to move and reorganize. By sequestering actin monomers, it is studied for effects on how cells migrate toward sites of tissue stress. A related line of research explores its role in recruiting repair-associated cells to stressed areas. These mechanisms are drawn largely from laboratory and animal work rather than controlled human trials.

Studies have examined TB-500 and its parent protein, thymosin beta-4, in several regenerative contexts. A rat study assessed Achilles tendon healing using histopathological and biomechanical measures. Reviews have discussed thymosin beta-4 as a multi-functional regenerative peptide, and a recent review covered unapproved peptides studied for musculoskeletal injuries and athletic performance. Thymosin beta-4 has also been investigated as a target in human brain organoid models of Alzheimer disease. Evidence remains early.

Human safety data for TB-500 are limited. The animal studies focus on tissue and mechanical outcomes, and adverse events are not summarized in them. A 2026 review in Sports Medicine discussed the safety and efficacy of approved and unapproved peptides for musculoskeletal injuries, placing compounds like TB-500 within the unapproved category. TB-500 is not an approved therapeutic and is supplied only for laboratory research.

Research protocols have used 500 to 2,000 mcg per administration by the subcutaneous route, once weekly in the morning, with a loading phase before a lower-frequency maintenance phase. These protocols have run in 8-week blocks followed by 4 weeks off. Each CoreX order ships with a protocol guide describing these research parameters. This information describes published research practice only.