Thymosin Alpha-1 Tracker App
Log Clinical and Research Doses, Monitor Immune Labs, and Track T Cell Response
Thymosin Alpha-1 (Ta1) is a 28-amino-acid thymic peptide that acts as a potent modulator of adaptive and innate immune function — increasing T cell maturation, NK cell activity, dendritic cell activation, and cytokine balance. Unlike most peptides on this list, Thymosin Alpha-1 has received clinical approval in some countries under the brand name Zadaxin (SciClone Pharmaceuticals) for hepatitis B and hepatitis C treatment in immunocompromised patients. Shotlee tracks your dose logs, immune lab results, infection frequency, and cycle progress in one free app.
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What Is Thymosin Alpha-1?
Thymosin Alpha-1 is the N-terminal fragment of thymosin fraction 5, a thymic hormone complex first isolated in the 1970s by Allan Goldstein. It is a 28-amino-acid peptide that has since been identified as the primary immunologically active component of the thymic fraction, driving T cell precursor maturation into functional T helper and cytotoxic T cells in the thymus and periphery.
Thymosin Alpha-1 is the only peptide on the immune tracker list with formal clinical approvals: Zadaxin is approved in over 35 countries — including throughout Asia and parts of Europe — for hepatitis B, hepatitis C, and as an adjunct therapy in immunocompromised patients. Clinical trials have also studied it in the context of sepsis, COVID-19 severity reduction, and as a vaccine adjuvant. Its unique regulatory standing makes it the most clinically validated compound in the immune peptide category.
Unique Clinical Standing
Unlike most immune peptides, Thymosin Alpha-1 (Zadaxin) is clinically approved in over 35 countries for hepatitis and immune deficiency applications. It may require a prescription depending on your jurisdiction. Consult a physician.
Protocol Options
1.6 mg
Subcutaneous, twice weekly
Standard clinical dosing used in Zadaxin hepatitis B and C trials. Two injections per week, typically for 6–12 months in chronic viral hepatitis protocols.
900 mcg
Subcutaneous, daily
Higher-frequency research protocol for general immune support, chronic infection, or adjunct use. Daily dosing used in some COVID-19 and sepsis adjunct studies.
Clinical Research Highlights
Hepatitis B Response
Phase 3
Phase 3 trials in chronic HBV showed significant increases in HBe seroconversion and normalised ALT compared to placebo with 1.6 mg twice-weekly Zadaxin.
COVID-19 Adjunct
Studied
Multiple prospective cohort studies in China (2020) showed reduced ICU progression and 28-day mortality in severe COVID-19 patients receiving Thymosin Alpha-1.
Countries Approved
35+
Zadaxin (thymalfasin) is approved in over 35 countries for hepatitis B, hepatitis C, and immunocompromised patient management — unmatched regulatory breadth for an immune peptide.
Mechanism of Action
Promotes maturation of immature thymocytes into functional CD4+ T helper and CD8+ cytotoxic T cells — restoring cell-mediated immunity in immune-suppressed states.
Increases NK (natural killer) cell activity and cytotoxicity, enhancing surveillance and clearance of virally infected and neoplastic cells.
Upregulates dendritic cell (DC) activation and antigen presentation, improving the efficiency with which adaptive immune responses are mounted.
Modulates cytokine balance — promoting Th1 responses (IFN-gamma, IL-2) for antiviral defence while tempering excessive Th2 or Th17 inflammatory states that drive autoimmunity.
What to Track in Shotlee
Build a comprehensive immune monitoring record — doses, T cell counts, NK activity, infection frequency, and energy.
Dose Logs
Record every Thymosin Alpha-1 injection: date, dose (mcg/mg), site, and lot number. Track adherence across long clinical dosing cycles.
Immune Labs (CD4/CD8)
Log CD4 and CD8 T cell counts from each blood draw. Tracking the CD4/CD8 ratio over time reveals immune reconstitution progress.
NK Cell Activity
Record NK cell percentage and activity values from immunology panels. NK cell enhancement is a primary Thymosin Alpha-1 outcome marker.
Infection Frequency
Log every infection episode: type, severity, duration, and treatment. Track whether infection frequency and severity decline with ongoing Ta1 use.
Energy & Fatigue
Score daily energy and fatigue (0–10). Immune dysfunction is a major driver of chronic fatigue — track the correlation with immune recovery.
Cycle Tracking
Mark protocol start date, phase milestones (6-week, 12-week), and any dose adjustments. Long Zadaxin cycles require structured timeline logging.
Thymosin Alpha-1 vs Thymosin Beta-4 (TB-500): Understanding the Difference
Despite sharing the "Thymosin" name, Thymosin Alpha-1 and Thymosin Beta-4 (TB-500) are structurally unrelated and act through completely different mechanisms. Thymosin Alpha-1 is an immune modulator — its therapeutic target is the immune system (T cells, NK cells, dendritic cells). TB-500 is a tissue repair peptide — its target is actin-mediated cell migration, muscle and tendon healing.
Some advanced protocols combine both: TB-500 for structural tissue repair and Thymosin Alpha-1 for immune support during recovery or chronic illness. If stacking, log each compound separately in Shotlee to clearly attribute effects and avoid confounding your clinical data.
Log Each Peptide Separately in Shotlee
Thymosin Alpha-1 and TB-500 work via unrelated pathways. Separate Shotlee logs for each compound let you see clearly which is driving which effects in your protocol.
Protocol FAQs
Thymosin Alpha-1 (Zadaxin) is clinically approved in over 35 countries for chronic hepatitis B and C, and for immune support in immunocompromised patients. Research applications include chronic infections, sepsis adjunct therapy, COVID-19 severity reduction, and cancer immunotherapy adjunct. Track your protocol in Shotlee.
The standard clinical Zadaxin dose is 1.6 mg subcutaneously twice weekly. Clinical hepatitis protocols typically run for 6–12 months. Research protocols for general immune support may use 900 mcg daily. Always follow physician guidance for clinical indications.
As of 2026, Thymosin Alpha-1 (Zadaxin) is not FDA-approved in the United States. However, it is approved in over 35 other countries, including throughout Asia and parts of Europe, for hepatitis B, hepatitis C, and immunocompromised patient management. It is the most clinically validated immune peptide in this category.
Priority labs include CD4/CD8 T cell counts and ratio, NK cell percentage, lymphocyte subsets, and for hepatitis patients, HBV/HCV viral load, ALT, and AST. Log all values with dates in Shotlee to build a longitudinal immune monitoring record.
No. Despite sharing the Thymosin name, they are structurally unrelated peptides with completely different mechanisms. Thymosin Alpha-1 is an immune modulator targeting T cell maturation and NK cell activity. Thymosin Beta-4 (TB-500) is an actin-binding tissue repair peptide. They act on entirely different biological systems.
References
- [1]ReviewGoldstein AL, et al. "Thymosin alpha 1: biology and therapeutic applications." Expert Opin Biol Ther. 2009;9(5):593-608.
- [2]Clinical TrialLiu Q, et al. "Thymosin alpha 1 (Thymalfasin) for Severe COVID-19 Pneumonia." Front Immunol. 2020;11:2081.
- [3]FDASciClone Pharmaceuticals. Zadaxin (thymalfasin) prescribing information.
Track Your Thymosin Alpha-1 Protocol in Shotlee
Log every dose, record immune labs, monitor infection frequency, and track your adaptive immune response — all free in Shotlee.
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