Educational reference only — not medical advice. Nothing is sold on this site. Research compounds are not for human use.
Home>>Peptides>>Thymosin Alpha-1
Approved medicineHealing / anti-inflammatory

Thymosin Alpha-1

A thymic peptide approved in several countries — notably as Zadaxin — as an adjunct in chronic hepatitis B and as an immunomodulator, though it is not FDA-approved in the United States.

CompoundThymosin Alpha-1
CategoryImmunomodulatory thymic peptide
ClassHealing and Anti-Inflammatory Peptides
Evidence tierApproved medicine
WADA statusNot individually listed; verify current status if subject to testing
Sold on this siteNo — this is a reference database

Overview

Thymosin Alpha-1 — a immunomodulatory thymic peptide — sits in the "Approved medicine" tier of this catalog. This compound exists as an approved medicine in at least one major jurisdiction. Approval applies to specific, labeled indications and to the regulated product — not to compounded or research-grade copies.

A thymic peptide approved in several countries — notably as Zadaxin — as an adjunct in chronic hepatitis B and as an immunomodulator, though it is not FDA-approved in the United States.

Mechanism of Action

Thymosin alpha-1 is thought to modulate dendritic cell and T-cell function, promoting a more effective adaptive immune response. Its approved uses leverage this immunomodulation in viral hepatitis and, in some markets, as a vaccine adjuvant.

Research and Evidence

Clinical trial literature includes randomized studies in chronic hepatitis B and trials in sepsis and other immune contexts, with heterogeneous results. Regulatory approval varies widely by country.

Evidence in context: the Healing and Anti-Inflammatory Peptides class page collects the shared evidence themes and study-reading guidance for this category.

Safety and Side Effects

Approved formulations have a generally tolerable profile (injection-site reactions are the most common complaint). Unregulated "research" versions carry none of the manufacturing assurances of the registered product.

Educational notice: this entry describes published research and, where they exist, regulator labels. It is not medical advice and not a recommendation for use. Research-grade compounds have no verified human-safety data.

Frequently Asked Questions

What is the evidence tier of Thymosin Alpha-1?

Thymosin Alpha-1 is graded "Approved medicine" on this site. This compound exists as an approved medicine in at least one major jurisdiction. Approval applies to specific, labeled indications and to the regulated product — not to compounded or research-grade copies.

Is Thymosin Alpha-1 an approved medicine?

Thymosin Alpha-1 exists as an approved medicine in at least one major jurisdiction — but approval covers the regulated product and its labeled indications only. Compounded or research-grade versions of the same molecule are not the approved product.

Where can I read the primary studies for Thymosin Alpha-1?

The references section at the end of this entry links the key primary sources — regulator labels, trial registrations, and peer-reviewed papers. Our "How to Read a Peptide Study" guide explains how to evaluate them.

References

  1. ClinicalTrials.gov — registered thymosin alpha-1 studies. [source]
EM
Dr. Elena Marsh, PhDMolecular Pharmacology · Lead Editor

Written and maintained by the editorial team. Medically reviewed by Dr. James Okafor, MD (Internal Medicine).

Evidence tier: Approved medicine · Last reviewed: 2026-09-05 · Sources cited below.

Advertisement