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Telehealth TB-500

A plain-language reading of the TB-500 / thymosin beta-4 literature — what the cardiac, wound and repair studies actually measured, where the human evidence stops, and how compounded access really stands.

The full list of studies and FDA pages

TB-500 References: Open the source behind a claim

The numbered entries appear below the guide. Most repair sources tested whole thymosin beta-4, not the fragment.

Go back to the findingsRead the legal limit

How to find the study behind a claim

The source entries sit directly below this note. Entries 1–15 cover cells, wounds, hearts, and strokes. The work runs through 2024–2026. Most repair tests used whole thymosin beta-4 [5]. Entries 16–19 cover the law. They include a 2026 review of TB-500. Three FDA pages from 2026 follow it [16][17][18][19]. Each entry gives the study name and a link. DOI means a lasting web address for a paper. PubMed is a U.S. government library page. Either link lets you inspect what researchers tested.

For a TB-500 claim you want to check, match its number to the same number below.

  1. Irobi E, 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, et al. Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair. Nature. 2004;432(7016):466-472. ↗
  3. Malinda KM, et al. Thymosin beta4 accelerates wound healing. J Invest Dermatol. 1999;113(3):364-368. ↗
  4. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance (review noting mixed and negative preclinical results, including the mdx-mouse and porcine ischemia-reperfusion findings). Sports Med. 2026. ↗
  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, et al. 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. Smart N, et al. Thymosin β4 is an essential paracrine factor of embryonic endothelial progenitor cell-mediated vasculogenesis. Circulation. 2008. ↗
  8. Bock-Marquette I, et al. Thymosin beta4 is cardioprotective after myocardial infarction. Ann N Y Acad Sci. 2007;1112:51-62. ↗
  9. Stark C, et al. Cardioprotection by systemic dosing of thymosin beta four following ischemic myocardial injury. Front Pharmacol. 2013;4:149. ↗
  10. Peng H, et al. Thymosin-β4 prevents cardiac rupture and improves cardiac function in mice with myocardial infarction. Am J Physiol Heart Circ Physiol. 2014;307(5):H741-H751. ↗
  11. Srivastava D, Saxena A, Dimaio JM, Bock-Marquette I. Thymosin beta4 and cardiac repair. Ann N Y Acad Sci. 2010;1194:87-96. ↗
  12. Sosne G, et al. Activation of pro-resolving pathways mediate the therapeutic effects of thymosin beta-4. Front Immunol. 2024;15:1458684. ↗
  13. Morris DC, et al. A dose-response study of thymosin β4 for the treatment of acute stroke. J Neurol Sci. 2014;345(1-2):61-67. ↗
  14. Zhang Y, et al. Tβ4-exosome-loaded hemostatic and antibacterial hydrogel to improve vascularized wound repair. Mater Today Bio. 2025;31:101585. ↗
  15. Wang L, et al. Thymosin β4 improves the survival of cutaneous flaps of rat and activates Wnt/β-catenin signaling. Arch Med Sci. 2024. ↗
  16. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance (lists TB-500/thymosin β4 and BPC-157 among unapproved peptides; notes scarce human safety data and WADA-prohibited standing). Sports Med. 2026. ↗
  17. U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks — list entry 'Thymosin beta-4, fragment (LKKTETQ), also known as TB-500' placed in 503A Category 2, effective with the September 29, 2023 nominated-substances update. FDA.gov (verified 2026-05-29). ↗
  18. U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act — Category 1/Category 2 definitions, the 503A/503B framework, the bulks-list and PCAC nomination process, and the January 7, 2025 interim-policy revision. FDA.gov (verified 2026-05-29). ↗
  19. U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee — published agenda listing 'TB-500 (free base)' / 'TB-500 acetate' (with BPC-157, KPV, and MOTs-C) as bulk drug substances 'being considered for inclusion on the 503A Bulks List.' FDA.gov (verified 2026-05-29). ↗
  20. Cha HJ, Jeong MJ, Kleinman HK. Role of thymosin beta4 in tumor metastasis and angiogenesis. J Natl Cancer Inst. 2003. ↗
  21. 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. ↗
  22. 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. ↗
  23. 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. ↗
  24. Delcourt V, et al. TB500/TB1000 and SGF1000: A scientific approach for a better understanding of misbranded and adulterated drugs. Drug Test Anal. 2023. ↗