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Research / clinical peptide

Thymosin Alpha-1

Thymosin alpha-1 is a 28-amino-acid immune-modulating peptide used or approved in some countries and widely studied in immunology research worldwide.

By The Peptides Codex Editorial TeamIndividual review date not recorded

Page data last changed: . Chemistry registry snapshot: . Registry refreshes and identity assessments are separate from scientific content review.

Length
28 aa
Class
Research / clinical peptide
Function
Immune-modulating thymic peptide
Context
Approved or used in some countries for specific indications; research use elsewhere

Immune peptide with real clinical history in some markets — not just forum lore.

Also known as: Tα1 · thymalfasin · Zadaxin

Part of the Repair & recovery peptides cluster

Overview

Thymosin alpha-1 is a 28-amino-acid immune-modulating peptide used or approved in some countries and widely studied in immunology research worldwide.

Source & context

Biological / chemical source: Synthetic version of thymic peptide

Primary research or clinical context: Approved or used in some countries for specific indications; research use elsewhere

Immune education angle

Tα1 is discussed in contexts of T-cell related immune function and vaccine-response research. Regulatory availability differs sharply by country.

Structure & chemistry

Molecular identity & reference confidence

Source-supported reference

Reference values are taken from the cited molecular record or curated profile. A database match is not independent laboratory verification; modifications, counter-ions, and formulations can change the measured mass.

Molecular form
Thymosin Alpha-1 (source record; form not independently established)
Species
Not established by this molecular identity audit
Termini (N / C)
Not specified / Not specified

Average reference mass

Reference policy updated: 2026-10-05

Molecular formula
C129H215N33O55
Average reference mass
≈ 3,108.3
Identifiers

Chemistry values: PubChem · fetched 2026-10-01.

Clinical development snapshot

ClinicalTrials.gov lists 64 registered studies with “Thymosin Alpha-1” as an intervention (snapshot 2026-10-01). A registry footprint is not evidence of efficacy or approval.

Registered studies
64
Highest phase reached
Phase 4
Active in latest 100
18
Most recent update
2026-09-14
Most recently updated studies
NCTTitlePhaseStatusUpdated
NCT05339529Protective Effect of Thymosin α1 Against Negative Immune Dysregulation and Organ Dysfunction After Acute AortiNot applicablecompleted2026-09-14
NCT07780721Study of Adebrelimab Combined With Thymalfasin and Chemotherapy for Neoadjuvant Treatment of Esophageal CancerPhase 2not yet recruiting2026-08-21
NCT06139419The Impact of Thymosin α-1 on the Efficacy of Concurrent Chemoradiotherapy Followed by Immunotherpay ConsolidaPhase 2completed2026-08-03
NCT06821100Thymalfasin (Thymosin Alpha 1; Ta1) as an Enhancer of Vaccine Response Among Older Adults Receiving Booster DoPhase 1recruiting2026-07-16
NCT07675980Thymosin-α1 for Recurrent Implantation FailurePhase 3recruiting2026-06-30
NCT06024356Neoadjuvant Chemoradiotherapy Combined With PD-1 Inhibitor and Thymalfasin for Locally Advanced Mid-low Rectal—completed2026-06-18
See all on ClinicalTrials.gov →
Concentration math

Thymosin Alpha-1 — reconstitution calculator

Enter how much peptide is in the vial and how much diluent (e.g. bacteriostatic water) is added. The tool returns the resulting solution concentration — and, for any amount you type, the volume it corresponds to. This is educational arithmetic, not a dosing recommendation.

Reference form: Thymosin Alpha-1 (source record; form not independently established)Average reference mass: 3,108.3 Da

Syringe graduation
Solution concentration
5 mg/mL5,000 mcg/mL
mcg

Enter an amount to see the volume it corresponds to.

Educational concentration mathematics only. This tool does not recommend a dose, amount, or protocol, and nothing here is medical advice. Many peptides are not authorized by Health Canada for human use — see our reconstitution and bacteriostatic-water guides for context.

Open the Thymosin Alpha-1 calculator on its own page →

FAQ about Thymosin Alpha-1

What is Thymosin Alpha-1?+

Thymosin alpha-1 is a 28-amino-acid immune-modulating peptide used or approved in some countries and widely studied in immunology research worldwide.

What Canadian product status is recorded for Thymosin Alpha-1?+

Canadian product status for Thymosin Alpha-1 has not been verified in this profile. No verified record here does not mean no authorization exists. Status depends on the product, formulation and use; consult Health Canada's product records.

What is the typical length of Thymosin Alpha-1?+

Thymosin Alpha-1 is commonly described as approximately 28 amino acids (Research / clinical peptide).

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References & further reading

  1. 1.Simonova et al. (2025). Aging and Thymosin Alpha-1. Int J Mol Sci
  2. 2.Panatto et al. (2011). Utility of thymosin alpha-1 (Zadaxin) as a co-adjuvant in influenza vaccines: a review. J Prev Med Hyg
  3. 3.Goldstein (1994). Clinical applications of thymosin alpha-1. Cancer Invest
  4. 4.Wu et al. (2015). Thymosin alpha-1 treatment in chronic hepatitis B. Expert Opin Biol Ther
  5. 5.Garaci et al. (2024). Phenotypic drug discovery: a case for thymosin alpha-1. Front Med (Lausanne)
  6. 6.Chuang et al. (2026). Thymosin α-1 in Cancer Therapy: Immunomodulatory Mechanisms, Clinical Applications, and Translational Perspectives. Eur J Pharmacol
  7. 7.Wang et al. (2021). Thymosin Alpha-1 Has no Beneficial Effect on Restoring CD4+ and CD8+ T Lymphocyte Counts in COVID-19 Patients. Front Immunol
  8. 8.Yang et al. (2020). Thymosin alpha-1 blocks the accumulation of myeloid suppressor cells in NSCLC by inhibiting VEGF production. Biomed Pharmacother
  9. 9.PubChem — compound summary for Thymalfasin (CID 16130571)
  10. 10.Wikipedia — Thymosin alpha-1 (thymalfasin)
Disclaimer: Educational content only. Not medical advice. Not instructions for human use. Research peptides and unapproved products may be restricted or illegal to market for human consumption in your jurisdiction. Consult qualified professionals and applicable law.
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