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Thymosin Alpha-1

Immune Modulation

Thymosin Alpha-1 (Tα1) is a synthetic peptide that enhances the immune system's ability to defend against infections, tumors, and chronic inflammation. It is widely studied for its immunomodulatory effects in cancer therapy, hepatitis, HIV, and other conditions involving immune suppression. Though not FDA-approved in the U.S., it is approved in several countries for adjuvant use in immunocompromised patients.

Reconstitute
3 mL BAC + 5mg vial
17 mcg/unit
Daily Range
0.8–3.2 mg Subcutaneous (SQ)
2-3 times per week
Standard Dose
1.6 mg
Cycle
4–8 weeks
then reassess
immunostimulatoryToll-like receptorimmune modulationchronic infectionThymosin Alpha-1

Dosing & Reconstitution Guide

Clinical use abroad typically involves 1.6 mg injected subcutaneously 1–2 times weekly. These regimens are not approved in the U.S.

Standard / Gradual Approach

5mg Vialstandard
PhaseDoseVolume
Week 1300 mcg (0.3 mg)18 units (0.18 mL)
Weeks 2–8500 mcg (0.5 mg)30 units (0.30 mL)

Standard / Gradual Approach

10mg Vialstandard
PhaseDoseVolume
Week 1300 mcg (0.3 mg)9 units (0.09 mL)
Weeks 2–8500 mcg (0.5 mg)15 units (0.15 mL)

Protocol Summary

Subcutaneous (SQ): 2-3 times per week · Dose range 0.8–3.2 mg with gradual titration
Cycle Length: 4–8 weeks typical; reassess before extending

Frequency & Cycling

SubQ Injection

Administer 1.6 mg SubQ injection 2–3 times weekly. Standard cycle: 6–12 weeks. Maintenance protocols vary by condition; periodic reassessment of immune markers recommended.

🧪 Quick Start

Vial Size
5 mg
BAC Water
3 mL
Concentration
1.67 mcg/unit
Starting Dose
300 mcg (0.3 mg) (18 units (0.18 mL))
Maintenance Dose
500 mcg (0.5 mg) (30 units (0.30 mL))

Potential Benefits & Use Cases

Thymosin Alpha-1 is not FDA-approved. The information reflects published research and region-specific clinical use.
Enhances T-cell function and overall immune competence (human trial)
Reduces sepsis mortality by ~9% in clinical studies (human trial)
Improves vaccine response in elderly populations (human trial)
FDA orphan drug approval for melanoma, hepatocellular carcinoma, and lung cancer (FDA-approved)
Approved for chronic active hepatitis B treatment (human trial)
Excellent safety profile — doses up to 16 mg SC over 12 months with no significant toxicity (human trial)
Clinical data Strong preclinical Limited data

Mechanism of Action

→Activates toll-like receptors TLR3/4/9 on dendritic cells and monocytes
→Promotes T cell maturation and cytokine signaling via TLR2/NF-κB and TLR7/MyD88 pathways
→Enhances activity of natural killer (NK) cells and CD8+ cytotoxic T lymphocytes

Lifestyle & Optimization

timing

2x weekly SubQ injection.

diet

Nutrient-dense diet (vitamins C, D, zinc). Avoid excessive alcohol and smoking.

exercise

Moderate physical activity.

sleep

Adequate sleep and stress management for immune function.

Peptide Research & Preclinical Studies

Evidence-Based Research Findings

Study TitleType
Expert Opinion on Biological Therapy — Thymosin alpha 1 reviewReference
PMC — Thymosin alpha 1 in infectious diseasesReference
Annals of the New York Academy of Sciences — Thymalfasin for hepatitis B and C treatmentReference
Clinical Cancer Research — Thymosin alpha 1 in cancer treatment: preclinical and clinical studiesReference

Side Effects & Safety

Common Side Effects

• Mild fever, muscle aches, fatigue, chills

Contraindications & Warnings

• When combined with interferon: rare neutropenia, joint pain, rash
• ALT flares in chronic hepatitis B; TSH abnormalities in chronic hepatitis C

🧮 Dose Calculator

Concentration
16.7
mcg/unit
Draw Volume
30
units (0.300 mL)
For a 500 mcg dose, draw 30 units on a U-100 insulin syringe
🧬

Bioavailability & Absorption

SubQ Injection
High bioavailability due to direct lymphatic absorption into systemic immune compartments
Oral Administration
Poor absorption due to gastrointestinal degradation
Half-Life
Approx. 2 hours; biological activity may persist longer through immune cell stimulation
Degradation
Primarily degraded by proteolytic enzymes in the liver and kidney
Tissue Specificity
Acts on immune cells—T cells, dendritic cells, monocytes, NK cells
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Peptide Details

Molecular Weight
3108.32
Formula
C129H215N33O55
Sequence
Ac-Ser-Asp-Ala-Ala-Val-Asp-Thr-Ser-Ser-Glu-Ile-Thr-Thr-Lys-Asp-Leu-Lys-Ser-Glu-Ile-Ile-Cys-Cys-Thr-Tyr-Ile-Gln-Glu.THR-VAL-HIS
⚖️

Legal Status & Regulatory

RegionStatus
FDANot Approved
EUApproved
AustraliaNot Approved
CanadaNot Approved

Storage Instructions

Lyophilized (Powder)
refrigerate at 2–8 °C (35.6–46.4 °F) or freeze at −20 °C (−4 °F); after reconstitution, refrigerate and use within 7 days
Reconstituted (Mixed)
Refrigerate at 2–8 °C (35.6–46.4 °F); use within 7 days when using bacteriostatic water; avoid freeze–thaw