Is thymosin alpha-1 FDA-approved?

No. Despite being approved in over 35 countries as Zadaxin and having FDA orphan drug designation for hepatitis B, it has not received full FDA approval. It is available through compounding pharmacies in the US.

How does thymosin alpha-1 differ from thymosin beta-4 (TB-500)?

They are different peptides with different functions. Thymosin alpha-1 (28 amino acids) primarily modulates immune function via TLR2/TLR9. Thymosin beta-4 (43 amino acids) is involved in tissue repair and cell migration. Different genes, different receptors, different applications.

What is the standard clinical protocol?

The Zadaxin protocol uses 1.6 mg SC twice weekly. For general immune support, 1.6 mg twice weekly for 4-8 weeks. For acute illness, 1.6 mg daily for 7-14 days. Even at much higher doses, Ta1 shows no toxicity -- the body simply breaks down excess peptide into amino acids.

What is the recommended dose range for Thymosin Alpha-1?

The research dose range is 1.6 mg SC per dose (approved dose); research range 0.8–6.4 mg, administered via Subcutaneous, Once daily or every other day.

peptide dosing

Thymosin Alpha-1 Dosing & Reconstitution Guide

Complete dosing reference for Thymosin Alpha-1 (Immune Modulator). Covers reconstitution, dose range, titration schedule, pharmacokinetics, and storage protocols for research use.

Dosing Protocol

Route: Subcutaneous Frequency: Once daily or every other day Dose Range: 1.6 mg SC per dose (approved dose); research range 0.8–6.4 mg Cycle Length: Approved for chronic use (hepatitis B/C); typical research cycles 4–12 weeks Timing: Any consistent time

Reconstitution

Vial Size: 5mg Water Volume: 2.5mL Concentration: 2mg/mL

Storage

Lyophilized: −20 °C (−4 °F) Reconstituted: 2–8 °C (35.6–46.4 °F) Shelf Life: 28 days

Injection Sites

Abdomen, Thigh, Upper arm

Safety & Contraindications

Safety: One of the safest immune therapies available; well-tolerated even at doses 100x higher than therapeutic standard Most common complaint: temporary redness or stinging at injection site (10-15% of users), similar to a mosquito bite, lasting 30-60 seconds Mild "immune flu" possible: low-grade fatigue, body aches from cytokine circulation (sign of immune activation, not infection)

Contraindications: Organ transplant recipients (ABSOLUTE contraindication -- immune boosting can trigger fatal organ rejection); Patients on immunosuppressive therapy post-transplant; Hypersensitivity to thymosin alpha-1

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Thymosin Alpha-1 Dosing Guide Peptides for Immune Support

Research Use Only. The information on this page is compiled from published research literature and is provided for educational purposes only. It does not constitute medical advice. All compounds referenced are intended for in vitro research use by qualified laboratories and institutions.