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

> TB-500 references: the full citation list behind this digest — the thymosin beta-4 structural, wound, cardiac, neurological and Phase 1 studies, the 2024-2026 literature, and the FDA 503A sources.

The complete citation list — peer-reviewed studies on thymosin beta-4 and the TB-500 fragment, the 2024-2026 literature, and the FDA pages behind the legal-status page.

## About this reference list

Every quantitative claim on this site maps to a numbered TB-500 reference below. The peptide literature is cited to PubMed, with DOIs where available; the regulatory facts on the [TB-500 legal status](/legal-status) page are cited to the FDA. Where a study used full-length thymosin beta-4 rather than the `Ac-LKKTETQ` heptapeptide, that distinction is stated in the body text that cites it. The numbering matches the inline `[N]` markers throughout the digest.

## 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, 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, 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] 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/
[8] Qiu P, Wheater MK, Qiu Y, Sosne G. Thymosin beta4 promotes matrix metalloproteinase expression during wound repair. J Cell Physiol. 2006;208(2):361-368. https://pubmed.ncbi.nlm.nih.gov/16607611/
[9] Tumor and angiogenesis safety signal for thymosin β4 (overexpression in several cancers; implication in metastasis and tumor angiogenesis), as summarized in Goldstein AL, Hannappel E, Sosne G, Kleinman HK. Thymosin β4: a multi-functional regenerative peptide. Expert Opin Biol Ther. 2012;12(1):37-51. https://pubmed.ncbi.nlm.nih.gov/22074294/
[9b] Kim S, Kwon J. Thymosin beta 4 improves dermal burn wound healing via downregulation of receptor for advanced glycation end products in db/db mice. Biochim Biophys Acta. 2014;1840(12):3452-3459. https://pubmed.ncbi.nlm.nih.gov/25230158/
[10] Human clinical record for full-length thymosin β4 (Phase 1 IV safety/PK; topical ophthalmic RGN-259 dry-eye randomized trials; registered cardiac trials; an early injectable trial withdrawn), as documented in Ruff D, et al. Ann N Y Acad Sci. 2010;1194:223-229, and Goldstein AL, et al. Expert Opin Biol Ther. 2012;12(1):37-51. https://pubmed.ncbi.nlm.nih.gov/20536472/
[11] 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/
[12] El-Sayed N, et al. The combined impact of thymosin beta 4 and selenium on diabetic ulcers: a comparative study. Discover Biotechnology. 2025. https://doi.org/10.1007/s44340-025-00015-0
[13] Sosne G, 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/
[14] 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
[15] Wang L, et al. Thymosin β4 improves the survival of cutaneous flaps of rat and activates Wnt/β-catenin signaling. Arch Med Sci. 2024. https://doi.org/10.5114/aoms/186188
[16] Compliance and analytical record for TB-500 / thymosin β4: not approved for human consumption (research-supply use only); WADA-prohibited in and out of competition for the relevant classes and detected by LC-MS in equine and human matrices; predominant research routes intraperitoneal, intravenous, and topical/ophthalmic; no validated human PK half-life for the heptapeptide. Compiled in domains/tb500store-com/research.json (compound corpus tb-500@rev2). https://en.wikipedia.org/wiki/TB-500
[17] U.S. Food and Drug Administration. Certain Bulk Drug Substances for Use in Compounding That May Present Significant Safety Risks. Category 2 entry: "Thymosin beta-4, fragment (LKKTETQ), also known as TB-500" (effective with the September 29, 2023 nominated-substances 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
[18] 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; the 503A/503B framework; the bulks-list nomination and PCAC process; verified 2026-05-29). https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a-fdc-act
[19] U.S. Food and Drug Administration. July 23-24, 2026: Meeting of the Pharmacy Compounding Advisory Committee. Published agenda lists "TB-500 (free base)" / "TB-500 acetate" (with BPC-157, KPV, and MOTs-C) as bulk drug substances being considered for inclusion on the 503A Bulks List — a scheduled discussion, not a decision (verified 2026-05-29). 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, Section 503A access framework (licensed-prescriber evaluation, including compliant telehealth, to a valid patient-specific prescription dispensed by a state-licensed 503A pharmacy or sourced from an FDA-registered 503B outsourcing facility; bulk ingredient must be eligible under 503A/503B rules; flagged substances are not eligible for routine 503A compounding while that status stands), as compiled in the audited config/regulatory-access-503a.json (verified 2026-05-29). https://www.fda.gov/drugs/human-drug-compounding/bulk-drug-substances-used-compounding-under-section-503a-fdc-act

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TB-500 Store runs the thymosin beta-4 literature as a single luminous pipeline — the Ac-LKKTETQ fragment traced from actin binding to tissue repair, every full-length-protein substitution flagged in line, the empty human-trial node left lit, and FDA's 503A standing read before anything else; a research repository, not a clinic, a vendor, or a prescription.