Thymosin Alpha-1

What is Thymosin Alpha-1?

Thymosin Alpha-1, also called thymalfasin or TA-1, is a 28-amino-acid thymic peptide used internationally as Zadaxin and in the United States through non-FDA-approved peptide channels. Its core role is immune modulation: TA-1 helps dendritic cells bridge innate and adaptive immunity, nudges T-helper signaling toward antiviral Th1 activity, supports CD4/CD8 recovery in lymphopenic states, and may improve monocyte HLA-DR expression in sepsis-induced immune suppression.

From the BioHarmony report, reviewed 2026-09-08.

How it is thought to work

TLR9 and TLR2 signaling on dendritic cells, NF-kB activation, Th1 polarization, CD4/CD8 normalization, NK-cell support, and IDO-mediated immune tolerance.

Safety watch-outs

• Injection-site infection
• Autoimmune flare symptoms

Full risk profile in the BioHarmony report.

Dosing as published

No approved-label or study protocol is recorded for Thymosin Alpha-1 yet.

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