TB-500 vs Thymosin Beta-4
A neutral, side-by-side comparison of two healing & recovery peptides — their mechanisms, dosing ranges, administration routes, side effects, and research evidence. For research and educational purposes only.
TB-500
TB-500 is a synthetic fragment of Thymosin Beta-4, an endogenous protein involved in cell migration, tissue repair, and inflammation regulation. It has shown significant healing properties in preclinical models across muscle, tendon, ligament, and cardiac tissue.
Full profileThymosin Beta-4
Thymosin Beta-4 (TB4) is the full-length 43-amino acid peptide produced naturally in high concentrations in platelets, wound fluid, and regenerating tissue. It is the parent molecule from which the popular TB-500 research peptide (the 17-23 fragment Ac-LKKTETQ) is derived. TB4 promotes actin polymerization, accelerates wound healing, reduces inflammation, and supports cardiac and neurological repair in preclinical models.
Full profile| TB-500 | Thymosin Beta-4 | |
|---|---|---|
| Category | Healing & Recovery | Healing & Recovery |
| Also known as | Thymosin Beta-4, Tβ4, TB500 | TB4, Tβ4, Tβ4 full-length |
| Evidence | Preclinical only | Investigational (in trials) |
| Dosing range | 2mg–10mg mg, twice weekly (loading), weekly (maintenance) | 500mcg–2000mcg mcg, 2–3x weekly |
| Administration | Subcutaneous injection, Intramuscular injection | Subcutaneous injection, Intramuscular injection, Intravenous (clinical studies only) |
| Key side effects | Head rush / lightheadedness (transient), Lethargy at higher doses, Injection site discomfort, Nausea (rare) | Injection site discomfort (mild), Transient fatigue post-injection, Headache (uncommon), Theoretically may accelerate growth of pre-existing malignant tumors (promotes angiogenesis and cell migration — use with caution) |
| Cited sources | 2 references | 3 references |
Key differences
- Evidence level differs: TB-500 is preclinical only, while Thymosin Beta-4 is investigational (in trials).
- Administration: TB-500 — Subcutaneous injection, Intramuscular injection; Thymosin Beta-4 — Subcutaneous injection, Intramuscular injection, Intravenous (clinical studies only).
- Dosing units differ: TB-500 is dosed in mg, Thymosin Beta-4 in mcg — they operate at different scales.
- Frequency: TB-500 is typically twice weekly (loading), weekly (maintenance); Thymosin Beta-4 is 2–3x weekly.
- Research depth: this profile cites 2 sources for TB-500 vs 3 for Thymosin Beta-4.
How each works
TB-500
TB-500 promotes healing by upregulating actin, which drives cell migration to injury sites. Animal studies show accelerated repair of muscle tears, tendon injuries, and corneal wounds. It also demonstrates anti-inflammatory properties and has been studied for cardiac tissue repair following ischemic injury.
Thymosin Beta-4
TB4's primary mechanism involves sequestering G-actin monomers (via its LKKTET actin-binding domain) to regulate actin cytoskeleton dynamics — critical for cell migration, wound closure, and tissue remodeling. Clinical trials have evaluated TB4 for corneal wound healing (Phase 2), pressure ulcers, and cardiac repair after MI. The FACT trial investigated TB4 in patients with ischemic heart failure, showing trends toward improved cardiac function. Anti-inflammatory effects are mediated partly through NF-κB pathway downregulation.
This comparison aggregates public research and structured profile data for informational purposes only. It is not medical advice and does not recommend either compound for human use. Consult a qualified healthcare provider before considering any peptide.