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TB-500 Order

How can you find the full report?

Where do the sources behind TB-500 claims lead?

The lab substance is smaller than the natural protein behind most repair experiments. You’ll find studies and official pharmacy sources here. A claim’s small number leads to the matching report below.

Return to what happened in the experimentsReturn to the prescription questions

How can you find out who was actually treated?

TB-500 differs from thymosin beta-4, the protein behind most of the repair experiments. These reports can help with the questions you bring to your doctor. Match the small number beside a finding with the numbered source below. Check who received treatment and whether the study gave thymosin beta-4 or the smaller substance.

The prescription discussion uses FDA sources to explain ingredient rules [16][17][18]. Those rules concern medicine a pharmacy prepares for a particular patient. Permission to prepare medicine doesn’t show that your injury will improve. Treatment evidence and pharmacy rules answer different questions for you.

Which numbers lead to the health studies?

Reports 1–15 cover the health research discussed here. You can find a study by looking for your topic below. Each entry includes a link and the study details.

  • Hair experiments in animals: 1–5; wound healing: 8.
  • How the proteins fit together: 6.
  • Reviews examining several kinds of repair: 7 and 12.
  • Mouse hearts: 9; stroke rats: 10; new vessels: 11.
  • Phase 1, the early safety test of thymosin beta-4 in people: 13.
  • The heart-attack trial ending before anyone joined: 14.
  • Sports Medicine’s 2026 review of unapproved repair treatments: 15.

Which reports address what your pharmacy may prepare?

Sources 16–19 address the pharmacy rules and the advisers’ meeting. FDA’s page current as of April 22, 2026 describes the withdrawn TB-500 request and retains the Category 2 safety concerns [16]. That group warned about serious possible harm, without giving temporary pharmacy permission. Section 503A, the law for a particular patient’s specially prepared medicine, is covered at [17].

The July 23–24, 2026 papers show FDA staff opposed allowing TB-500 as an ingredient [18]. The advisers’ vote hadn’t been published by September 2026. General prescription and pharmacy rules appear at [19]. Your pharmacist still lacks a settled answer about permission after withdrawal.

  1. Philp D, et al. Thymosin beta4 increases hair growth by activation of hair follicle stem cells. FASEB J. 2004;18(2):385-387. ↗
  2. Philp D, et al. Thymosin beta 4 induces hair growth via stem cell migration and differentiation. Ann N Y Acad Sci. 2007;1112:95-103. ↗
  3. Gao X, et al. Thymosin Beta-4 Induces Mouse Hair Growth. PLoS One. 2015;10(6):e0130040. ↗
  4. 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. ↗
  5. Philp D, et al. Thymosin beta4 promotes angiogenesis, wound healing, and hair follicle development. Mech Ageing Dev. 2004;125(2):113-115. ↗
  6. Irobi E, et al. Structural basis of actin sequestration by thymosin-beta4: implications for WH2 proteins. EMBO J. 2004;23(18):3599-3608. ↗
  7. 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. ↗
  8. Malinda KM, et al. Thymosin beta4 accelerates wound healing. J Invest Dermatol. 1999;113(3):364-368. ↗
  9. 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. ↗
  10. 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. ↗
  11. 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. ↗
  12. Kleinman HK, Sosne G. Animal studies with thymosin beta, a multifunctional tissue repair and regeneration peptide. Ann N Y Acad Sci. 2010;1194:118-122. ↗
  13. 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. ↗
  14. RegeneRx (sponsor). A Study of the Safety and Efficacy of Injectable Thymosin Beta 4 for Treating Acute Myocardial Infarction (WITHDRAWN). ClinicalTrials.gov, 2011. Identifier NCT01311518. ↗
  15. Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance. Sports Med. 2026. ↗
  16. 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'; effective 2023-09-29). ↗
  17. 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; bulks-list and nomination framework). ↗
  18. U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee (agenda listing BPC-157, KPV, TB-500, and MOTs-C as bulk drug substances being considered for inclusion on the 503A Bulks List). ↗
  19. U.S. Food and Drug Administration. Human Drug Compounding — Section 503A patient-specific compounding and 503B outsourcing-facility framework (access pathway: licensed-prescriber evaluation, valid prescription, dispensing by a 503A pharmacy or sourcing from a 503B outsourcing facility, subject to ingredient-eligibility requirements). ↗
  20. RegeneRx (sponsor). A Study of the Safety and Efficacy of Injectable Thymosin Beta 4 for Treating Acute Myocardial Infarction. ClinicalTrials.gov. 2011. ↗
  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. ↗