MyPepShelf.

← Shelf·Thymic 28-residue peptide (acetylated)·XXVI.

Thymosin Alpha-1.

A 28-amino-acid N-acetylated peptide originally isolated from thymic tissue by Allan Goldstein and Abraham White in the mid-1970s at what became George Washington University. The compound corresponds to the INN thymalfasin, which is approved as a prescription drug in roughly 35 countries for hepatitis B, hepatitis C, and certain immunocompromised patient populations — but is NOT FDA-approved in the United States.

Your thymus (in youth) and other tissues produce prothymosin α, which is processed to yield thymosin α-1. Circulating levels decline substantially with thymic involution across the adult lifespan. This is a synthetic version of the same sequence, produced to a research-grade specification.


Marketed across the wellness and longevity market with immune-modulation claims that read differently in the FDA-authorized labeling of the approved product overseas. The compound is real; the international approval record is real; the specific claims common in US-market consumer copy substantially overstate what any approved label authorizes.

Straight talk

Straight talk: thymosin α-1 has an unusually well-documented international regulatory record for a compound in this catalog — approved in ~35 countries, decades of clinical trial data, particularly in Hep B and Hep C. What is available in the US-affiliate market is not that regulated pharmaceutical. Whether the research-grade compound in a given vial IS the same molecule as the internationally-approved drug of the same INN is exactly what a third-party COA is for. Buy on documentation, not on brand adjacency.

What the research studies

The literature, not a summary of it.

The foundational work is Allan Goldstein's group at GW University. International clinical development anchored by SciClone (US) and various national programs. Journals: Ann N Y Acad Sci, Expert Opin Biol Ther, Int Immunopharmacol, J Hepatol. Read the research yourself:

Recommended vendor · Amino Club

≥ 99% by HPLC on the current lot — ILS Laboratories (ISO/IEC 17025).

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