Educational content only. Not medical advice, and no doctor-patient relationship is created. Read the medical disclaimer
Peptide
Thymosin Alpha-1
Also known as: Thymalfasin
A thymus peptide that helps tune the immune system, approved abroad for hepatitis B and as a vaccine add-on.
Tier 3 · Education only
Grade B · Strong evidence, different label
Educational content only, not medical advice. Discussion here does not mean this therapy is prescribed by Youthful Medicine or available to you. Read the medical disclaimer
U.S. regulatory status
Not FDA-approved in the U.S. Approved as thymalfasin in more than 30 countries. Not eligible for U.S. compounding after a 2024 advisory review; the subject of ongoing litigation.
What it is
A 28-amino-acid peptide first isolated from the thymus, the gland where T cells mature.
How it is thought to work
It supports T-cell maturation and the cells that present threats to them. It acts more as a modulator than a stimulant.
Animations simplify biology for teaching. They are not a claim that this peptide works this way in people.
What the research shows
Human trials exist in chronic hepatitis B and C, as an add-on to cancer therapy and in severe infections, with mixed but real results.
Safety and considerations
Generally well tolerated in trials. Its role in autoimmune disease is unclear and needs specialist judgment.
Our position
The natural anchor of this quadrant and a strong teaching example of modulation versus stimulation. Education only in the U.S. today.
Video lesson
AT A GLANCE
Quadrant
Autoimmunity & Inflammation
Tier
Tier 3 · Education only
Evidence grade
Grade B · Strong evidence, different label
Last reviewed
Is this right for you?
Only a physician who has evaluated you can answer that. Consultations are with licensed Youthful Medicine providers.
Never use products labeled “research use only” or “not for human use.” Purity, dose and sterility are unverified.