peptideThymosin Alpha-1
peptide

Thymosin Alpha-1.

4.3
Reviewed by Pierson Riley — Founder, UtritionReviewed under Utrition’s editorial methodologyLast reviewed Mar 2026Allergen-free

Immune-modulating peptide approved in some countries.

peptideimmuneresearch
Evidence
B
Moderate evidence
Best time
Morning
Medical supervision required
Typical dose
Primary use
Peptide
Quick answer

Thymosin Alpha-1 in one minute. Immune-modulating peptide approved in some countries. Take in the morning. Should be used under medical care.

What is Thymosin Alpha-1?

Thymosin Alpha-1 (Zadaxin) is a thymic peptide approved in multiple countries (not US) for immune support in hepatitis and cancer. It has more clinical data than many research peptides.

Immune support under medical supervision

Keep reading

What is Thymosin Alpha-1?

Immune-modulating peptide approved in some countries.

Thymosin Alpha-1 (Zadaxin) is a thymic peptide approved in multiple countries (not US) for immune support in hepatitis and cancer. It has more clinical data than many research peptides.

What the evidence says

The overall evidence grade for Thymosin Alpha-1 is B (moderate — mixed or smaller trials, reasonable mechanistic support). Approved in multiple countries. Clinical trial data exists.

Specific findings with supporting evidence:

Best-supported outcomes:

Where marketing outpaces evidence:

Dose and timing

Take it in the morning. Medical supervision required.

Who it's for, and who should skip it

Most relevant for:

Not appropriate for:

Safety and cautions

Caution: Not FDA approved. Approved elsewhere but not in US. Important: Medical supervision. Should be used under medical care.

Common mistakes

Myths vs reality

A common misconception: TA1 is a general immune booster anyone can use. In reality, it has specific approved indications requiring medical supervision.

How it interacts with other compounds

Questions people ask

Where is Thymosin Alpha-1 approved? Multiple countries including some in Asia and Europe, but not the US.

Editorial note

This guide summarizes the published evidence on Thymosin Alpha-1. It is educational content, not medical advice. Confirm with your clinician if you take prescription medications or manage a chronic condition.