Thymosin Beta-4 (TB-4)
Also known as TB-4, Tβ4, Thymosin Beta 4, Thymosin β4
Thymosin Beta-4 is the full 43-amino acid peptide from which TB-500 (the 17–23 fragment) is derived. While TB-500 contains the primary actin-binding motif, the full TB-4 molecule has broader biological activity including cardiac repair, neuroregeneration, and stem cell mobilization. Used for advanced recovery and anti-aging protocols.
How it works
Binds G-actin monomers, regulating actin dynamics critical to cell migration and repair. Activates ILK (Integrin-Linked Kinase) signaling, promotes angiogenesis via upregulation of HIF-1α and VEGF, and stimulates stem cell homing to sites of injury. The full peptide also has distinct activity at receptors not engaged by the TB-500 fragment.
Benefits
- Promotes actin polymerization and cell migration for tissue repair
- Cardiac protection and regeneration after injury
- Neuroregeneration and axonal growth
- Reduces inflammation and scar tissue formation
- Mobilizes stem cells from bone marrow
- Angiogenesis — promotes new blood vessel formation in damaged tissue
- Broader biological activity than TB-500 alone
Dosing
1000–5000 mcg · 2–3x per week
Loading phase: higher doses for 4 weeks. Maintenance: lower doses 1–2x/week. Can be used alongside TB-500 for complementary activity.
Ranges reflect commonly cited research protocols, not a prescription. Dose with a licensed provider.
Reconstitution
Reconstitute 5mg vial with 2mL BAC water = 2.5mg/mL
Helix’s free reconstitution calculator gives you the exact draw volume → get the app
Common stacks
Reported side effects
- Generally well tolerated
- Injection site irritation
- Potential mild fatigue
- Theoretical concern with promoting angiogenesis in cancerous tissue — avoid if active cancer
Who it’s for
Advanced users seeking maximum tissue repair, cardiac support, or neurological recovery. Most appropriate when TB-500 alone is insufficient or for specific indications like cardiac or neural injury. Requires more careful dosing than TB-500.
Track Thymosin Beta-4 (TB-4) in Helix
Dose reminders, reconstitution math, vial tracking, and AI guidance — free on iOS.
Download free