# TB-500 References: The Cited Thymosin Beta-4 and Regulatory Sources

> The full TB-500 reference list — peer-reviewed thymosin beta-4 studies with PubMed and DOI links, plus the primary FDA 503A and PCAC sources for the legal-status page.

The peer-reviewed thymosin beta-4 literature and the primary FDA sources behind the legal-status page — checkable, with DOIs, PMIDs, and FDA URLs.

## How to read this list

Each entry below carries the identifier needed to verify it — a PubMed ID, a DOI, an NCT registration number, or an FDA URL. Where an experiment used full-length thymosin beta-4 rather than the TB-500 fragment, that distinction is stated in the body of the relevant page, and most efficacy entries here are full-length-protein studies [5]. The regulatory entries (18 through 23) are the primary and authoritative sources for the legal-status page, drawn from FDA.gov and verified loading on 2026-05-29. The full numbered list renders below.

## References

[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. https://pubmed.ncbi.nlm.nih.gov/15329672/
[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. https://pubmed.ncbi.nlm.nih.gov/15565145/
[3] Malinda KM, Sidhu GS, Mani H, et al. Thymosin beta4 accelerates wound healing. J Invest Dermatol. 1999;113(3):364-368. https://pubmed.ncbi.nlm.nih.gov/10469335/
[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. https://pubmed.ncbi.nlm.nih.gov/25060418/
[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. https://pubmed.ncbi.nlm.nih.gov/22074294/
[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. https://pubmed.ncbi.nlm.nih.gov/20536472/
[7] Smart N, Risebro CA, Melville AAD, et al. Thymosin β4 induces adult epicardial progenitor mobilization and neovascularization. Nature. 2007;445(7124):177-182. https://doi.org/10.1038/nature05383
[8] Smart N, Rossdeutsch A, Riley PR. Thymosin β4 and angiogenesis: modes of action and therapeutic potential. Circulation. 2008;117(15):1907-1909. https://doi.org/10.1161/circulationaha.107.758904
[9] Bock-Marquette I, Shrivastava S, Srivastava D. Thymosin beta4 is cardioprotective after myocardial infarction. Ann N Y Acad Sci. 2007;1112:343-357. https://pubmed.ncbi.nlm.nih.gov/17600280/
[10] Stark C, Taimen P, Tarkia M, et al. Cardioprotection by systemic dosing of thymosin beta four following ischemic myocardial injury. Front Pharmacol. 2013;4:149. https://pubmed.ncbi.nlm.nih.gov/24348421/
[11] ClinicalTrials.gov. Thymosin beta-4 in acute myocardial infarction (NCT05984134), registered as completed; an earlier injectable thymosin β4 acute-stroke trial was withdrawn. (Trial-registry record establishing the absence of completed human efficacy data for the TB-500 fragment.) https://clinicaltrials.gov/study/NCT05984134
[12] Morris DC, Chopp M, Zhang L, Lu M, Zhang ZG. Thymosin beta4 improves functional neurological outcome in a rat model of embolic stroke. Neuroscience. 2010;169(2):674-682. https://pubmed.ncbi.nlm.nih.gov/20627173/
[13] Peng H, Xu J, Yang XP, 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. (Cardiac-rupture / function finding; the tumor-angiogenesis safety signal is reviewed in Goldstein 2012 [5].) https://pubmed.ncbi.nlm.nih.gov/25015963/
[14] Mendias CL, Awan TM. Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance. Sports Med. 2026. https://pubmed.ncbi.nlm.nih.gov/41966639/
[15] Sosne G, Qiu P, Kurpakus-Wheater M, et al. Activation of pro-resolving pathways mediate the therapeutic effects of thymosin beta-4. Front Immunol. 2024;15:1458684. https://pubmed.ncbi.nlm.nih.gov/39380984/
[16] Zhang Y, et al. Tβ4-exosome-loaded hemostatic and antibacterial hydrogel to improve vascularized wound repair. Mater Today Bio. 2025;31:101585. https://doi.org/10.1016/j.mtbio.2025.101585
[17] U.S. Food and Drug Administration. Bulk Drug Substances Used in Compounding Under Section 503A of the FD&C Act. FDA.gov (verified 2026-05-29). Definitions of Category 1 and Category 2 and the bulks-list / nomination framework. https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a-fdc-act
[18] U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks. FDA.gov. Category 2 entry for 'Thymosin beta-4, fragment (LKKTETQ), also known as TB-500'; effective with the September 29, 2023 update (page verified 2026-05-29). https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
[19] U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee. FDA.gov (verified 2026-05-29). Public calendar listing BPC-157, KPV, TB-500, and MOTs-C as substances 'being considered for inclusion on the 503A Bulks List' — a scheduled discussion, not a decision. https://www.fda.gov/advisory-committees/advisory-committee-calendar/july-23-24-2026-meeting-pharmacy-compounding-advisory-committee-07232026
[20] U.S. Food and Drug Administration. Interim Policy on Compounding Using Bulk Drug Substances Under Section 503A of the FD&C Act (guidance landing page). FDA.gov (guidance finalized January 2025; verified 2026-05-29). Underlies the January 7, 2025 change to how nominated bulk substances are categorized, and the 503A/503B access framework. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/interim-policy-compounding-using-bulk-drug-substances-under-section-503a-federal-food-drug-and
[21] McDermott Will & Emery. End of an Era: FDA Retires 2017 Interim Policies for Bulk Drug Lists. mcdermottlaw.com (analysis of the January 7, 2025 FDA action; verified 2026-05-29). Secondary legal analysis confirming that existing Category 1 substances retain enforcement discretion while Category 2 substances do not regain it. https://www.mcdermottlaw.com/insights/end-of-an-era-fda-retires-2017-interim-policies-for-bulk-drug-lists/
[22] World Anti-Doping Agency. The Prohibited List. wada-ama.org. TB-500 and thymosin beta-4 fall under prohibited peptide, growth-factor, and tissue-repair categories, banned in and out of competition; detected by LC-MS anti-doping assays in equine and human matrices. https://www.wada-ama.org/en/prohibited-list

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A deadpan twilight digest of the TB-500 record — the seven-residue fragment read honestly against the forty-three-residue protein it is mistaken for, its FDA and WADA standing stated first, with no clinic behind the frame and nothing here prescribed or sold.