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Medicine TB-500

studies and official rules behind each claim

A healing claim catches your eye: check the TB-500 references

You can match every numbered note to a study or official page. The list covers TB-500, full thymosin beta-4, FDA rules, and sport bans.

Return to the study findingsCheck the current legal rules

What each source helps you check

The numbered notes on each page lead you to these references. Entries 1–18 are studies or reviews about TB-500 and thymosin beta-4.

A DOI is a permanent number that helps you find one study. PubMed is a free catalog where you can search a study's title or number.

Entries 19–22 are FDA pages behind the TB-500 legal status facts. Each main page tells you whether researchers used TB-500 or full thymosin beta-4, so you can keep the two apart.

  1. Irobi E, Aguda AH, Larsson M, et al. Structural basis of actin sequestration by thymosin-beta4: implications for WH2 proteins. EMBO J. 2004;23(18):3599-3608. ↗
  2. Bock-Marquette I, Saxena A, White MD, DiMaio JM, Srivastava D. Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair. Nature. 2004;432(7016):466-472. ↗
  3. Malinda KM, Sidhu GS, Mani H, et al. Thymosin beta4 accelerates wound healing. J Invest Dermatol. 1999;113(3):364-368. ↗
  4. Morris DC, Cui Y, Cheung WL, et al. A dose-response study of thymosin β4 for the treatment of acute stroke. J Neurol Sci. 2014;345(1-2):61-67. ↗
  5. Goldstein AL, Hannappel E, Sosne G, Kleinman HK. Thymosin β4: a multi-functional regenerative peptide. Basic properties and clinical applications. Expert Opin Biol Ther. 2012;12(1):37-51. ↗
  6. Ruff D, Crockford D, Girardi G, Zhang Y. A randomized, placebo-controlled, single and multiple dose study of intravenous thymosin β4 in healthy volunteers. Ann N Y Acad Sci. 2010;1194:223-229. ↗
  7. Qiu P, Wheater MK, Qiu Y, Sosne G. Thymosin beta4 inhibits TNF-alpha-induced NF-kappaB activation, IL-8 expression, and the sensitizing effects by its partners PINCH-1 and ILK. FASEB J. 2011;25(6):1815-1826. ↗
  8. Sosne G, Qiu P, Christopherson PL, Wheater MK. Thymosin beta 4 suppression of corneal NFkappaB: a potential anti-inflammatory pathway. Exp Eye Res. 2007;84(4):663-669. ↗
  9. Kumar S, Vijayan M, Bhatti JS, et al. Thymosin β4 alleviates renal fibrosis and tubular cell apoptosis through TGF-β pathway inhibition in UUO rat models. BMC Nephrol. 2017;18(1):314. ↗
  10. Evans MA, Smart N, Dubé KN, et al. Thymosin β4: A Multi-Faceted Tissue Repair Stimulating Protein in Heart Injury. Curr Med Chem. 2020;27(37):6294-6305. ↗
  11. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance. Sports Med. 2026. ↗
  12. Zhu J, et al. Mechanism of thymosin β4 in ameliorating liver fibrosis via the MAPK/NF-κB signaling pathway. J Biochem Mol Toxicol. 2023;37(8):e23338. ↗
  13. Anti-doping LC-MS characterization of TB-500 (the Ac-LKKTETQ thymosin β4 fragment) and its metabolites in equine plasma and urine for detection (representative of the WADA-prohibited / detection literature; see Goldstein 2012 [5] and the Sports Med review [11] for the regulatory framing). ↗
  14. Kim J, et al. Targeted Deletion of Thymosin Beta 4 in Hepatic Stellate Cells Ameliorates Liver Fibrosis. Cells. 2023;12(12):1658. ↗
  15. Wei Y, et al. Inhaled exogenous thymosin beta 4 suppresses bleomycin-induced pulmonary fibrosis. J Pharm Pharmacol. 2024;76(12):1631-1642. ↗
  16. Sosne G, Dunn SP, Kim C. Thymosin β4 and the eye: the journey from bench to bedside (clinical-grade topical thymosin β4, RGN-259, in corneal healing and dry-eye trials). Reviewed in Goldstein AL et al., Expert Opin Biol Ther. 2012;12(1):37-51. ↗
  17. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance (on the scarcity of human safety data, the regulatory-oversight gap, and research-material quality concerns for unapproved peptides). Sports Med. 2026. ↗
  18. Xing Y, Ye Y, Zuo H, Li Y. Progress on the Function and Application of Thymosin β4. Front Endocrinol (Lausanne). 2021;12:767785. ↗
  19. U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee (calendar listing BPC-157, KPV, TB-500, and MOTS-c as bulk drug substances being considered for inclusion on the 503A bulks list). ↗
  20. U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act (Category 1 and Category 2 definitions; enforcement-discretion policy; January 7, 2025 finalized interim policy on categorization). ↗
  21. U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks (Category 2 entry for 'Thymosin beta-4, fragment (LKKTETQ), also known as TB-500'; effective with the September 29, 2023 update; safety rationale including potential immunogenicity for certain routes and a lack of important safety information). ↗
  22. U.S. Food and Drug Administration. Compounding and the FDA: 503A compounding pharmacies and 503B outsourcing facilities; the prescriber-evaluation and valid-prescription pathway, and the bulk-substance eligibility requirement (USP/NF monograph, component of an approved drug, or on the applicable bulks list). ↗
  23. Cha HJ, Jeong MJ, Kleinman HK. Role of thymosin beta4 in tumor metastasis and angiogenesis. J Natl Cancer Inst. 2003. ↗
  24. Zhang Y, et al. Thymosin beta 4 is overexpressed in human pancreatic cancer cells and stimulates proinflammatory cytokine secretion and JNK activation. Cancer Biol Ther. 2008. ↗
  25. Ho EN, et al. Doping control analysis of TB-500, a synthetic version of an active region of thymosin β4, in equine urine and plasma by liquid chromatography-mass spectrometry. J Chromatogr A. 2012. ↗
  26. Spurney CF, et al. Evaluation of skeletal and cardiac muscle function after chronic administration of thymosin beta-4 in the dystrophin deficient mouse. PLoS One. 2010. ↗
  27. Delcourt V, et al. TB500/TB1000 and SGF1000: A scientific approach for a better understanding of misbranded and adulterated drugs. Drug Test Anal. 2023. ↗