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healing · recovery

TB-500

Also known as: Thymosin Beta-4, TB4, Tβ4, Timbetasin
FDA: Not FDA-approved WADA: Prohibited

TB-500 is a synthetic version of Thymosin Beta-4 (Tβ4), a naturally occurring 43-amino-acid peptide found in virtually all human and animal cells. It is the primary actin-sequestering molecule in mammalian cells and plays a central role in cell migration, wound healing, and tissue repair. Unlike BPC-157, which works best when injected near the injury site, TB-500 is fully systemic — inject it anywhere and it travels to sites of injury throughout the body. Originally isolated from thymus extract in the 1960s, Tβ4 is encoded by the X-linked TMSB4X gene and is one of the most highly conserved peptides in nature.

This content is for educational and research purposes only. VialBase does not provide medical advice. Consult a healthcare professional before using any peptide.

Molecular weight 4,963.44 Da
Half-life ~14 days
CAS number —
Route Subcutaneous · Intramuscular · Topical subcutaneous preferred
02

Mechanism

Upregulates actin, promotes cell migration via Akt/mTOR pathway, reduces inflammation, stimulates angiogenesis, modulates NF-κB

03

Dosing

DOSE RANGE 2000–5000 mcg
FREQUENCY 2x weekly
CYCLE LENGTH 4-8 weeks loading, 4 weeks maintenance

Systemic — inject anywhere, not site-specific like BPC-157

04

Research summary

Study Type Year Key Finding
Therapeutic peptides: molecular signaling networks in orthopaedic medicine Narrative review 2026 TB-500 and TB-4 promote angiogenesis and tissue repair in preclinical models
A revised model of nuclear actin import: Importin 9 competes with cofilin, profilin, and RanGTP for actin binding Basic research 2026 Importin 9 competes with cofilin, profilin, and RanGTP for actin binding
The Tβ4-Ac-SDKP Axis in Kidney Disease: Renoprotective Efficacy Review Review 2026 Tβ4 and its metabolite Ac-SDKP act as dynamic mediators of renal injury and repair
Comparative Proteomic Analysis of the Secretome of Control and BRAF/MEK Inhibitor-Resistant Melanoma Cells Proteomic analysis 2026 Thymosin Beta-4 identified in secretome of BRAF/MEK inhibitor-resistant melanoma cells
TB-500 (Thymosin Beta-4) for Cardiovascular Disease / ASCVD — — —
Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair animal study 2004 Thymosin beta-4 promotes cardiac cell survival after ischemia
Thymosin beta 4 promotes corneal wound healing and decreases inflammation in vivo following alkali injury animal study 2002 Tβ4 accelerated corneal wound healing after alkali burn
Thymosin beta 4 speeds corneal wound healing and decreases inflammation in the clinical setting review 2016 RGN-259 (Tβ4 eye drops) advanced through clinical trials for corneal healing
Thymosin β4, a multi-functional actin-sequestering protein involved in tissue repair review 2012 Comprehensive review of Tβ4 tissue repair mechanisms
05

Stacking & interactions

Local + systemic healing synergy

Enhanced wound healing and tissue remodeling

GH-mediated recovery amplification

Stacks containing TB-500

Marquee

Glow Stack

GHK-Cu + BPC-157 + TB-500

 Marquee

Wolverine Stack

BPC-157 + TB-500

Athletic Recovery

BPC-157 + TB-500 + CJC/Ipamorelin

Recovery & Repair

BPC-157 + TB-500 + GHK-Cu

Tendon Armor

BPC-157 + TB-500 + Pentadecapeptide

28-day resets featuring TB-500

06

Sourcing

Current prices

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5mg

10mg

Size unspecified

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Also vetted at
What bloodwork do I need?

Reference ranges are general guidelines. Consult your physician for interpretation.

PRE-CYCLE
  • CMP
  • CBC
  • CRP
DURING CYCLE
  • CBC
  • CRP
POST-CYCLE
  • CMP
  • CBC
Safety & Regulatory Status
FDA STATUS Not FDA-approved. FDA Category 2 (under evaluation for compounding)
WADA STATUS Prohibited (S0 — non-approved substances, effective 2011)

Regulatory status for TB-500 may change. Verify current status with your jurisdiction before use. This is not legal or medical advice.

References

  1. Various. Therapeutic peptides: molecular signaling networks in orthopaedic medicine. Orthopaedic Review (2026). PMID: 41476424
  2. Keplinger AJ, Srinivasan PA, Christensen SM, Suarez C, Ruthenburg AJ. A revised model of nuclear actin import: Importin 9 competes with cofilin, profilin, and RanGTP for actin binding. Journal of Biological Chemistry (2026). PMID: 41570941
  3. Various. The Tβ4-Ac-SDKP Axis in Kidney Disease: Renoprotective Efficacy Review. Renal Review (2026). PMID: 41742019
  4. Simiczyjew A, Surman M, Kot M, Przybyło ME, Nowak D. Comparative Proteomic Analysis of the Secretome of Control and BRAF/MEK Inhibitor-Resistant Melanoma Cells. Journal of Proteome Research (2026). PMID: 41966639
  5. TB-500 (Thymosin Beta-4) for Cardiovascular Disease / ASCVD.
  6. Bock-Marquette, I., Saxena, A., White, M.D. et al.. Thymosin beta4 activates integrin-linked kinase and promotes cardiac cell migration, survival and cardiac repair. Nature (2004). PMID: 15538359
  7. Sosne, G., Szliter, E.A., Barrett, R. et al.. Thymosin beta 4 promotes corneal wound healing and decreases inflammation in vivo following alkali injury. Experimental Eye Research (2002). PMID: 12137760
  8. Sosne, G., Dunn, S.P., Kim, C.. Thymosin beta 4 speeds corneal wound healing and decreases inflammation in the clinical setting. Expert Opinion on Biological Therapy (2016). PMID: 27537216
  9. Goldstein, A.L., Hannappel, E., Sosne, G. et al.. Thymosin β4, a multi-functional actin-sequestering protein involved in tissue repair. Expert Opinion on Biological Therapy (2012). PMID: 22171665