NOT MEDICAL ADVICE

Thymosin Alpha-1

Estimated Market Price
$119.99 $134.99
Based on verified supplier pricing for research-grade compounds
MW: 3108.21 g/mol | Purity: >=98% HPLC | Lyophilized powder, 5mg/vial
How it works

Trains your immune system by maturing T-cells, activating natural killer cells, and boosting antigen presentation. Acts as an immune "tune-up" that strengthens defenses while also promoting tolerance to prevent overreaction.

Recovery & Longevity

What to Expect
Week 1–2 Dendritic cell and NK cell activation ramping up. No obvious feeling; immune system quietly strengthening.
Week 3–4 T-cell maturation enhanced; improved immune surveillance. May notice you're getting sick less often.
Week 5–8 Th1 response optimized; reduced infection susceptibility. Immune resilience up; recovery from illness faster.
Week 9–12 Full immunomodulatory benefit; reassess based on labs. Overall health feels more robust and consistent.

Verified Suppliers

For research purposes only. These suppliers have been independently verified by PepSpace. We do not process sales directly.

PepSpace is not affiliated with any listed supplier
Protocol & Dosage
Typical Dosage 1.6 mg SC, 2x weekly
Administration Subcutaneous injection
Schedule Twice weekly (e.g., Mon/Thu)
Protocol Duration 4–12 weeks
Half-Life ~2 hours
Side Effects & Safety
Tolerability Profile Favorable

Very well tolerated; side effects are rare and mild

Common Side Effects

  • Injection site rednessmost users
  • Mild warmth at injection sitesome users

Less Common

  • Temporary fatigueoccasional
  • Headacheoccasional
  • Mild flu-like symptoms (immune activation)occasional

Discontinue If

  • Severe allergic reaction
  • Signs of autoimmune flare (new or worsening symptoms)
  • Persistent fever

Contraindications

  • Active autoimmune disease (unmonitored)
  • Organ transplant recipients on immunosuppressants
  • Pregnancy or breastfeeding

Data note: Approved in 35+ countries (Zadaxin) for hepatitis B/C and as immune adjunct. Extensive safety record over 20+ years of clinical use.

Always consult a qualified healthcare professional before use. This information is for research reference only and does not constitute medical advice.

Ask about Thymosin Alpha-1
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How to Apply

1

Gather

Peptide vial, BAC water, alcohol swabs, insulin syringe

2

Sanitize

Wipe tops of both vials with alcohol swabs

3

Draw

Pull 1–2 mL of BAC water into syringe

4

Add Water

Release water slowly along vial wall, not directly on powder

5

Swirl

Roll between palms until dissolved. Never shake.

6

Store

Refrigerate 2–8°C, use within 30 days

Frequently Asked Questions

Yes. Bacteriostatic water (BAC water) is required to reconstitute lyophilized (freeze-dried) peptides. It contains 0.9% benzyl alcohol which prevents bacterial growth, keeping your reconstituted peptide safe for multiple uses over up to 30 days.

Unreconstituted: store at -20°C (freezer) for long-term, or 2–8°C (fridge) for short-term. After reconstitution: always refrigerate at 2–8°C and use within 30 days. Keep away from direct sunlight.

Results vary by individual and protocol. In research settings, measurable effects are typically observed within 1–4 weeks depending on the specific peptide, dosage, and application. Consult a qualified professional for guidance.

Verified suppliers typically include a full third-party COA verifying purity (99%+), identity, and sterility. We recommend only sourcing from vendors that provide batch-specific testing data.

We list verified suppliers above that have been independently reviewed for product quality, testing transparency, and shipping reliability. Always verify COA data before sourcing.

Compound Profile

Scientific data & classification for Thymosin Alpha-1

Also Known As Thymalfasin, Tα1, Zadaxin
Classification Polypeptide · Immunomodulator
Sequence Ac-SDAAVDTSSEITTKDLKEKKEVVEEAEN (28 aa)
Molecular Formula C₁₂₉H₂₁₅N₃₃O₅₅
Molecular Weight 3,108.27 Da
CAS Number 62304-98-7
Half-Life ~2 hours
Origin Naturally produced by the thymus gland
Administration Subcutaneous injection
Status Approved in 35+ countries - hepatitis B/C, immunodeficiency
Mechanism of Action Trains your immune system by maturing T-cells, activating natural killer cells, and boosting antigen presentation. Acts as an immune "tune-up" that strengthens defenses while also promoting tolerance to prevent overreaction.
Research Overview Thymosin alpha-1 (Tα1) is a 28-amino-acid polypeptide originally isolated from thymus gland tissue extracts by Allan Goldstein at the George Washington University in the 1970s, representing one of the first thymic peptides to be identified, sequenced, and developed as a pharmaceutical agent. The synthetic form, thymalfasin (marketed as Zadaxin), has been approved for clinical use in over 35 countries - primarily in Asia and Europe - for the treatment of chronic hepatitis B, chronic hepatitis C (as adjunct therapy), and for immune enhancement in immunocompromised patients. Tα1's mechanism of action centers on its role as a biological response modifier that amplifies T-cell-mediated immune responses without the risks of generalized immune stimulation. The peptide activates dendritic cells through Toll-like receptor 9 (TLR9) signaling, promotes the maturation and differentiation of T-cell precursors in the thymus, enhances the function of natural killer cells, and stimulates the secretion of type I interferons and IL-2. A particularly elegant aspect of its mechanism was elucidated by Romani and colleagues, who demonstrated that Tα1 activates the indoleamine 2,3-dioxygenase (IDO) pathway in dendritic cells, promoting tryptophan catabolism via the kynurenine pathway - this simultaneously enhances anti-pathogen immune responses while maintaining immune tolerance and preventing autoimmune pathology, a dual action rarely achieved with immunomodulatory agents. Clinical studies in chronic hepatitis B demonstrated that Tα1 treatment, either alone or in combination with interferon-alpha, produced significantly higher rates of sustained virological response and HBeAg seroconversion compared to interferon alone. During the COVID-19 pandemic, several clinical studies from China suggested that Tα1 treatment reduced mortality and accelerated immune recovery in severely ill patients, though these studies had methodological limitations. The compound has also been investigated as an adjunct to cancer immunotherapy and vaccination in elderly immunocompromised individuals.

Citations

Published findings on Thymosin Alpha-1 from peer-reviewed journals.

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