Immune SupportStrong Evidence

Thymosin Alpha-1 Peptide Therapy

Benefits, Side Effects, Cost & Protocols

Thymosin Alpha-1 peptide molecular structure diagram from PubChem

Thymosin alpha-1 (thymalfasin) is a peptide naturally produced by the thymus gland that plays a critical role in immune system modulation. It enhances T-cell function, natural killer cell activity, and dendritic cell maturation. It is approved in several countries for hepatitis B and C treatment and as an immune adjuvant.

ByChris Riley(CFA)&Alex Evans, PharmD, MBA(PharmD, MBA)|Updated May 19, 2026

Clinically Reviewed

Reviewed by Alex Evans, PharmD, MBA · Updated May 2026

Evidence-Based

Sourced from FDA, PubMed & ClinicalTrials.gov · View sources

FDA Status

Banned from Compounding March 2024 Removed from bulk drug substance list for compounding. FDA found insufficient evidence for compounding use.

Evidence

Strong Evidence

Who Is Thymosin Alpha-1 Best For?

Immune modulationT-cell supportTissue repair support

How Thymosin Alpha-1 Works

Enhances T-cell function, dendritic cell maturation, and overall immune response modulation.

Thymosin Alpha-1 FAQ

What is THYMOSIN ALPHA-1?

Thymosin Alpha-1 is a thymic peptide with established immune-modulating properties, researched for immune enhancement and as an adjunct in various health conditions.

How does THYMOSIN ALPHA-1 work?

Enhances T-cell function, dendritic cell maturation, and overall immune response modulation.

Is THYMOSIN ALPHA-1 legal to buy?

THYMOSIN ALPHA-1 is sold as a research chemical for laboratory use only. It is not approved for human use by the FDA. Regulations vary by jurisdiction.

Where can I buy THYMOSIN ALPHA-1?

THYMOSIN ALPHA-1 has mixed availability - it can be found through both compounding pharmacies (with prescription) and research suppliers.

What category does THYMOSIN ALPHA-1 belong to?

THYMOSIN ALPHA-1 is primarily classified as a immune support peptide. Peptides researched for immune modulation, antimicrobial activity, and immune system support.

What are the research benefits of THYMOSIN ALPHA-1?

THYMOSIN ALPHA-1 has been studied for: Immune modulation, T-cell support, Tissue repair support. Immune modulation; established research peptide.

Key Studies

858 total on PubMed0

Thymosin alpha-1

Am J Health Syst PharmPhase 3

Thymosin alpha-1 shows modest efficacy for hepatitis B and improved outcomes when combined with interferon for hepatitis C

Thymosin Alpha 1 Plus Routine Treatment for the Acute Exacerbation of Chronic Obstructive Pulmonary Disease: A Systematic Review and Meta-Analysis

J Coll Physicians Surg Pak

Thymosin alpha 1 improved pulmonary function, blood oxygen, and shortened hospital stay in AECOPD patients

Comparison of the efficacy of thymosin alpha-1 and interferon alpha in the treatment of chronic hepatitis B: a meta-analysis

Yang YF, Zhao W, Zhong YD et al

Antiviral Res · Antiviral Res

6 months treatment plus 6 months follow-up

Talpha1 showed delayed benefit versus IFNalpha, with superior virological response at 6-month follow-up

The efficacy of thymosin alpha-1 therapy in moderate to critical COVID-19 patients: a systematic review, meta-analysis, and meta-regression

Soeroto AY, Suryadinata H, Yanto TA et al

Inflammopharmacology

Thymosin alpha-1 reduced COVID-19 mortality in moderate-to-critical patients versus placebo

Thymosin Alpha-1 Compound Data

Molecular Formula

C129H215N33O55

Molecular Weight

3108.3 g/mol

IUPAC Name

(4S)-4-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S,3R)-2-[[(2S,3R)-2-[[(2S,3S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S,3R)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-[[(2S)-2-acetamido-3-hydroxy-propanoyl]amino]-3-carboxy-propanoyl]amino]propanoyl]amino]propanoyl]amino]-3-methyl-butanoyl]amino]-3-carboxy-propanoyl]amino]-3-hydroxy-butanoyl]amino]-3-hydroxy-propanoyl]amino]-3-hydroxy-propanoyl]amino]-4-carboxy-butanoyl]amino]-3-methyl-pentanoyl]amino]-3-hydroxy-butanoyl]amino]-3-hydroxy-butanoyl]amino]-6-amino-hexanoyl]amino]-3-carboxy-propanoyl]amino]-4-methyl-pentanoyl]amino]-6-amino-hexanoyl]amino]-4-carboxy-butanoyl]amino]-6-amino-hexanoyl]amino]-6-amino-hexanoyl]amino]-4-carboxy-butanoyl]amino]-3-methyl-butanoyl]amino]-3-methyl-butanoyl]amino]-4-carboxy-butanoyl]amino]-4-carboxy-butanoyl]amino]propanoyl]amino]-5-[[(1S)-3-amino-1-carboxy-3-oxo-propyl]amino]-5-oxo-pentanoic acid

View full compound on PubChem

Thymosin Alpha-1 News

I Reviewed Over 100 Peptide Studies—These 4 Findings Stood Out the Most - Men's Health

Men's Health · today

Thymosin α1 alleviates pulpitis by inhibiting ferroptosis of dental pulp cells - Nature

Nature · 7 months ago

Q&A: Should you trust trending peptide injections? - UVA Today

UVA Today · 1 month ago

RFK Jr. May Reverse a Peptide Ban He Calls “Illegal.” Former FDA Officials Say He Mischaracterized Their Work. - ProPublica

ProPublica · 1 month ago

Peptide Stacking Is Everywhere—But Should You Be Doing It? - Goop

Goop · 1 month ago

News aggregated via Google News. Inclusion does not imply endorsement.

Medical Disclaimer: The information on this page is for educational purposes only and does not constitute medical advice. Peptide therapies have not been evaluated by the FDA for most listed indications.All prices shown are estimates based on publicly available data and may not reflect current pricing — providers and brands set their own prices and can change them at any time. Always verify pricing directly with the provider before purchasing. Consult a licensed healthcare provider before starting any peptide protocol.

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