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

> TB-500 references: every study and FDA source cited across this thymosin beta-4 research console, with PMIDs, DOIs, and direct links to the primary literature and FDA pages.

The full source register behind this console — peer-reviewed thymosin beta-4 studies and the FDA pages underlying the 503A status, each with its identifier.

## How to read this register

Every quantitative claim across this TB-500 console resolves to a numbered source below. Entries 1–15 are peer-reviewed studies and reviews on thymosin beta-4 and its LKKTETQ fragment, each with its PMID or DOI. Entries 16–20 are the FDA and regulatory sources behind the [FDA 503A compounding access](/legal-status) page. Where a finding rests on full-length thymosin beta-4 rather than the TB-500 heptapeptide, the body copy says so at the point of citation — the distinction is load-bearing throughout this site. Links resolve to PubMed, the journal of record, or FDA.gov.

## References

[1] Irobi E, 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, et al. 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, 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, 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, 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. https://pubmed.ncbi.nlm.nih.gov/20536472/
[7] Grant DS, et al. Thymosin beta4 and angiogenesis: modes of action and therapeutic potential. Angiogenesis. 2007;10(2):137-145. https://pubmed.ncbi.nlm.nih.gov/17632766/
[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. https://pubmed.ncbi.nlm.nih.gov/20691219/
[9] Sosne G, Qiu P, Christopherson PL, Wheater MK. Thymosin β4 Promotes Dermal Healing. Vitam Horm. 2016;102:251-275. https://pubmed.ncbi.nlm.nih.gov/27450738/
[10] 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/
[11] Gao X, et al. Thymosin Beta-4 Induces Mouse Hair Growth. PLoS One. 2015;10(6):e0130040. https://pubmed.ncbi.nlm.nih.gov/26083021/
[12] Philp D, et al. Thymosin beta4 promotes angiogenesis, wound healing, and hair follicle development. Mech Ageing Dev. 2004;125(2):113-115. https://pubmed.ncbi.nlm.nih.gov/15037013/
[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. https://pubmed.ncbi.nlm.nih.gov/33393222/
[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. https://pubmed.ncbi.nlm.nih.gov/33754060/
[15] Zhang Y, et al. Tβ4-exosome-loaded hemostatic and antibacterial hydrogel to improve vascularized wound repair. Mater Today Bio. 2025;32:101585. https://doi.org/10.1016/j.mtbio.2025.101585
[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). https://www.fda.gov/drugs/human-drug-compounding/certain-bulk-drug-substances-use-compounding-may-present-significant-safety-risks
[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). 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. 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). https://www.fda.gov/advisory-committees/advisory-committee-calendar/july-23-24-2026-meeting-pharmacy-compounding-advisory-committee-07232026
[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. https://www.fda.gov/regulatory-information/search-fda-guidance-documents/interim-policy-compounding-using-bulk-drug-substances-under-section-503a-federal-food-drug-and
[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. https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a-fdc-act

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A luminous console reading of the thymosin beta-4 literature — the Ac-LKKTETQ fragment mapped apart from the full-length protein it is sold as, the empty human-trial node and the FDA 503A status left lit, and no clinic behind the readout nor anything here dispensed.