TB-500 Order

REFERENCES

TB-500 references and sources

Every quantitative claim on this site maps to a numbered entry below — peer-reviewed studies, FDA pages, and the PCAC meeting agenda.

Back to the researchRead the legal status

How these references are used

This is the full study reference list for the digest. Research findings come from the peer-reviewed literature on thymosin beta-4 and the Ac-LKKTETQ fragment; the regulatory facts on the TB-500 legal status page come from FDA pages and the FDA Pharmacy Compounding Advisory Committee agenda, listed separately below [16][17][18]. Where a study used full-length thymosin beta-4 rather than the 7-mer, that is noted in the body where the finding appears.

Peer-reviewed studies and reviews

Entries 1–15 are the research citations carried inline across the digest. Hair-follicle and tissue-repair findings (1–5, 8), mechanism and structural work (6), consolidated reviews (7, 12), cardiac, neurological and angiogenic studies (9, 10, 11), the human Phase 1 of full-length thymosin beta-4 (13), the withdrawn stroke trial (14), and the 2026 Sports Medicine review of unapproved peptides (15) are all listed in the index with DOIs, PMIDs or trial identifiers.

Regulatory sources

Entries 16–19 are the FDA and FDA-advisory sources behind the legal-status page: the FDA significant-safety-risks listing that places the LKKTETQ fragment (also known as TB-500) in Category 2 [16], the FDA Section 503A bulk-substances framework page [17], the July 23–24, 2026 PCAC meeting agenda naming TB-500 among substances being considered for the bulks list [18], and the FDA access-pathway framework for compounded medications [19].

  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 Stroke (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). ↗