Compare Peptides
Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.
Popular comparisons
The full-length 43-amino acid peptide from which TB-500 is derived. Thymosin Beta-4 is the most abundant member of the beta-thymosin family and plays a central role in tissue repair, cell migration, and anti-inflammatory signaling.
A thymic peptide that plays a central role in immune system regulation. Approved as a drug in over 35 countries (though not in the US) for hepatitis B and C treatment and as an immune booster.
Sequesters G-actin monomers, regulating actin polymerization critical for cell motility and wound healing. Promotes angiogenesis, reduces inflammation via NF-κB modulation, and supports stem cell differentiation. TB-500 is a synthetic fragment of the active region.
Enhances T-cell function, promotes dendritic cell maturation, and modulates cytokine production. Acts as an immune system regulator rather than a simple stimulant, helping to balance immune responses.
- Tissue repair and wound healing
- Cardiac tissue protection
- Corneal healing
- Anti-inflammatory support
- Hair regrowth
- Immune system support
- Chronic infection management
- Cancer adjunct therapy (in some countries)
- Post-illness recovery
- Autoimmune condition management
- Limited human clinical data for injectable form
- Theoretical oncogenesis concerns (promotes cell migration)
- More expensive than TB-500 fragment
- Injection site reactions
- Generally well-tolerated in clinical use
- Injection site reactions
- Rare allergic reactions
- May interact with immunosuppressive drugs
No FDA regulatory category for the full-length peptide. TB-500 (the fragment) is pending PCAC review. The full-length Thymosin Beta-4 is available only as a research chemical.
Reclassified to Category 1 in February 2026 as part of the HHS announcement restoring compounding access. Not affected by the April 15, 2026 Category 2 removal action. Approved as Zadaxin in 35+ countries but not FDA-approved in the US. Available through licensed 503A compounding pharmacies with a physician prescription.
- Thymosin β4 and its role in tissue repair
2012 · PubMed
This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.