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TB-500 Medicine

A dark research console on TB-500 (Ac-LKKTETQ) — what the thymosin beta-4 literature actually maps, where the human data stop, and how compounded access really stands.

SOURCES / WHERE EACH CLAIM CAME FROM

Where can you check the TB-500 claims?

You can open the studies and FDA pages below. They show whether a claim came from people or from lab work. None can predict what the beta-4 copy will do for you.

Return to the findingsCheck the legal status

What each source can help you check

Every numbered TB-500 claim points to a source below. Entries 1–15 are studies or reviews of the beta-4 protein and its small copy. Each entry gives the paper's title and a web link. I would start with the source beside the claim that matters most to you.

Entries 16–20 are FDA records used on the FDA pharmacy rules page, which also says when a finding used the full beta-4 protein instead of TB-500. That difference matters because the two haven't proved the same effects. Some links open PubMed, a free U.S. medical-library page; others open the paper or FDA.gov. I would bring the paper to your doctor and ask which source best fits your health question.

  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. 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. ↗
  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. Grant DS, et al. Thymosin beta4 and angiogenesis: modes of action and therapeutic potential. Angiogenesis. 2007;10(2):137-145. ↗
  8. Jo JO, et al. Thymosin β4 induces the expression of vascular endothelial growth factor (VEGF) in a hypoxia-inducible factor (HIF)-1α-dependent manner. Biochim Biophys Acta. 2010;1803(11):1244-1251. ↗
  9. Sosne G, Qiu P, Christopherson PL, Wheater MK. Thymosin β4 Promotes Dermal Healing. Vitam Horm. 2016;102:251-275. ↗
  10. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance. Sports Med. 2026. ↗
  11. Gao X, et al. Thymosin Beta-4 Induces Mouse Hair Growth. PLoS One. 2015;10(6):e0130040. ↗
  12. Philp D, et al. Thymosin beta4 promotes angiogenesis, wound healing, and hair follicle development. Mech Ageing Dev. 2004;125(2):113-115. ↗
  13. Xiao X, et al. Multiple potential roles of thymosin β4 in the growth and development of hair follicles. J Cell Mol Med. 2021;25(3):1350-1358. ↗
  14. Chen Y, et al. Thymosin β4 released from functionalized self-assembling peptide activates cardiac cells and promotes cardiac repair. Theranostics. 2021;11(10):4974-4986. ↗
  15. Zhang Y, et al. Tβ4-exosome-loaded hemostatic and antibacterial hydrogel to improve vascularized wound repair. Mater Today Bio. 2025;32:101585. ↗
  16. U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks (entry: "Thymosin beta-4, fragment (LKKTETQ), also known as TB-500"; Category 2, effective with the September 29, 2023 update). ↗
  17. U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act (503A/503B framework; Category 1 and Category 2 definitions; nomination and PCAC process). ↗
  18. U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee (agenda listing "TB-500 (free base)" / "TB-500 acetate," alongside BPC-157, KPV, and MOTs-C, as substances being considered for inclusion on the 503A Bulks List; scheduled discussion, not a decision). ↗
  19. U.S. Food and Drug Administration. Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the FD&C Act (finalized January 2025); note: reported early-2026 reclassification of Category 2 peptides could not be confirmed as a completed, effective FDA action as of 2026-05-29 and is not stated here as fact. ↗
  20. U.S. Food and Drug Administration. Compounding pathway under Sections 503A and 503B of the FD&C Act: licensed-prescriber evaluation (including compliant telehealth as a front-end channel), valid patient-specific prescription, dispensing by a state-licensed 503A pharmacy or FDA-registered 503B outsourcing facility, subject to bulk-substance ingredient eligibility. ↗
  21. Cha HJ, Jeong MJ, Kleinman HK. Role of thymosin beta4 in tumor metastasis and angiogenesis. J Natl Cancer Inst. 2003. ↗
  22. 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. ↗
  23. 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. ↗
  24. 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. ↗
  25. Delcourt V, et al.. TB500/TB1000 and SGF1000: A scientific approach for a better understanding of misbranded and adulterated drugs. Drug Test Anal. 2023. ↗