The immune-modulating peptide approved in 35+ countries — strengthens T-cell immunity without overstimulation, used for chronic infection, post-COVID recovery, and Lyme.
Thymosin Alpha-1 (TA1 or Tα1) is a 28 amino acid peptide naturally produced by the thymus gland. Its synthetic form (branded Zadaxin / Thymalfasin) is approved in more than 35 countries for chronic hepatitis B, hepatitis C, sepsis, and as an adjunctive immune therapy in cancer.
Unlike broad immune stimulants, TA1 modulates — it boosts under-functioning T-cell responses without triggering inflammatory overshoot. This makes it valuable for chronic infections, immunosenescence, and post-illness recovery.
Approved in 35+ countries (not US). Not WADA prohibited. Available through international pharmacies and research suppliers.
Promotes maturation of naive T-cells into effector cells in the thymus — compensating for age-related thymic involution.
Restores balance between Th1 (antiviral, antibacterial) and Th2 (antibody) responses. Corrects the skew toward chronic inflammation seen in aging and chronic infection.
Enhances natural killer cell activity and dendritic cell antigen presentation — critical for clearing infected or transformed cells.
Paradoxically tamps down excessive inflammation — protective in sepsis and autoimmune settings. It is a regulator, not just a booster.
| Benefit | Evidence |
|---|---|
| Chronic hepatitis B/C | Phase 3 trials show meaningful viral response and histological improvement |
| Sepsis | ETASS meta-analyses: reduced 28-day mortality in severe sepsis |
| COVID-19 | Liu et al. (2020): reduced mortality in severely ill COVID patients with lymphocytopenia |
| Chronic Lyme | Used off-label for immunomodulation in chronic Lyme protocols |
| Cancer adjunct | Improves response to chemo and immunotherapy in several cancer trials |
| Vaccine response | Enhanced antibody response to influenza and hepatitis B vaccines in elderly |
Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeSome protocols use 1.6 mg daily for the first 2–4 weeks during acute infection, then drop to 2×/week maintenance.
Commonly supplied as 5 mg or 10 mg lyophilized powder.
5 mg vial + 2 mL BAC water = 2500 mcg/mL
| Dose | Volume | Syringe Units |
|---|---|---|
| 800 mcg | 0.32 mL | 32 units |
| 1.6 mg | 0.64 mL | 64 units |
5 mg vial at 1.6 mg 2×/week = ~10 days
Use our free peptide calculator to figure out your reconstitution volume, draw amount, and syringe units.
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One of the most tolerable peptides in clinical use — decades of approved use worldwide with excellent safety.
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Build your protocol, log every dose, monitor your body's response, and get reminders so you never miss a dose.
Start Tracking FreeDisclaimer: This guide is for educational and informational purposes only and is not intended as medical advice, diagnosis, or treatment. The compounds discussed are not FDA approved for human use. Always consult a qualified healthcare provider before starting any new supplement or peptide protocol. StackTrax does not sell peptides or supplements directly — purchase links go to third-party vendors. StackTrax is not responsible for the products, quality, or business practices of any third-party vendor. This page contains affiliate links — StackTrax may earn a commission on purchases at no extra cost to you.
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StackTrax guides cover peptides and compounds that are not FDA-approved for the uses discussed. The dosing, reconstitution, and safety information is compiled from published research and community protocols for educational purposes only.
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