TB-500 vs Thymosin Alpha-1
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 Alpha-1
Thymosin Alpha-1 (Tα1) is a 28-amino acid peptide naturally derived from the thymus gland. It plays a central role in regulating immune function — specifically in the maturation and differentiation of T-cells. Unlike most research peptides, Thymosin Alpha-1 has approved clinical use in multiple countries (China, Italy, and others) for hepatitis B, hepatitis C, and as an immune adjuvant in cancer patients undergoing chemotherapy. In the US it is sold as Zadaxin and used as a research compound.
Full profile| TB-500 | Thymosin Alpha-1 | |
|---|---|---|
| Category | Healing & Recovery | Healing & Recovery |
| Also known as | Thymosin Beta-4, Tβ4, TB500 | Tα1, Thymalfasin, Zadaxin |
| Evidence | Preclinical only | Research-stage |
| Dosing range | 2mg–10mg mg, twice weekly (loading), weekly (maintenance) | 900mcg–3.2mg mg, 2–3 times per week subcutaneously |
| Administration | Subcutaneous injection, Intramuscular injection | Subcutaneous injection |
| Key side effects | Head rush / lightheadedness (transient), Lethargy at higher doses, Injection site discomfort, Nausea (rare) | Generally very well tolerated, Mild injection site reactions (most common), Transient fatigue in initial doses, Flu-like symptoms (rare) |
| Cited sources | 2 references | 4 references |
Key differences
- Evidence level differs: TB-500 is preclinical only, while Thymosin Alpha-1 is research-stage.
- Administration: TB-500 — Subcutaneous injection, Intramuscular injection; Thymosin Alpha-1 — Subcutaneous injection.
- Frequency: TB-500 is typically twice weekly (loading), weekly (maintenance); Thymosin Alpha-1 is 2–3 times per week subcutaneously.
- Research depth: this profile cites 2 sources for TB-500 vs 4 for Thymosin Alpha-1.
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 Alpha-1
Extensive human clinical research documents Tα1's immune-modulating effects. It increases T-cell counts, enhances NK cell activity, and promotes Th1 cytokine balance. Multiple randomized trials have shown efficacy in treating chronic hepatitis B and C, reducing infection severity in critically ill patients, and improving outcomes in sepsis. More recent research investigates its role in long COVID immune dysregulation. It is considered one of the best-studied peptides in immunology.
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.