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HomeThymosin Alpha-1Legal status

Educational — Not Legal AdviceReviewed

Is Thymosin Alpha-1 legal? FDA status and US regulatory standing

Current status

Compounding nomination withdrawn. Thymosin Alpha-1 was nominated for the FDA bulk drug substances compounding list and was previously placed in a safety-review category before the nomination was withdrawn, so it does not appear on the current bulk substances lists.

Primary source: www.fda.gov

Federal legal status

FDA approval status

Thymosin Alpha-1 was nominated for the FDA bulk drug substances compounding list and was previously placed in a safety-review category before the nomination was withdrawn, so it does not appear on the current bulk substances lists. Approved as Zadaxin in China, Italy, and other countries but NOT FDA-approved. Not on FDA 503A Category 1 bulks list. Research use only in US. Immunomodulatory thymic peptide.

Also known as

Tα1 · Zadaxin

Frequently asked questions

Is Thymosin Alpha-1 FDA approved?
Thymosin Alpha-1 was nominated for the FDA bulk drug substances compounding list and was previously placed in a safety-review category before the nomination was withdrawn, so it does not appear on the current bulk substances lists. Primary source linked on this page.
Is Thymosin Alpha-1 legal to buy?
Thymosin Alpha-1 is available in the U.S. as a research-use-only compound. It was nominated for the FDA bulk drug substances compounding list and was previously placed in a safety-review category before the nomination was withdrawn, so it does not appear on the current bulk substances lists. Sale for human consumption is not permitted.
PeptideBase provides educational research tools and provider discovery. It does not provide medical advice, diagnosis, treatment, prescribing guidance, or dosing instructions. Consult a qualified healthcare professional before making health decisions.

Content review: Regulatory status is sourced from the linked primary records and reviewed by the PeptideBase editorial team. This page is educational — not legal or medical advice. Last reviewed: .

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