For research use only. Not for human consumption. Not medical advice — consult a licensed clinician.

Immune Modulator

Thymosin Alpha-1

Also known as: Thymalfasin (trade name Zadaxin)

Thymosin Alpha-1 (Ta1) is a 28-amino-acid thymic peptide (Ac-SDAAVDTSSEITTKDLKEKKEVVEEAEN) approved as Zadaxin in 35+ countries for chronic hepatitis B/C and as an immune adjuvant. It is NOT FDA-approved in the US.

Real-time market data

Pricing for Thymosin Alpha-1

Live vendor pricing, normalized to $/mg so sizes compare fairly — fused with each seller's Merit trust score and latest independent COA purity. Prices refresh daily.

Average price

$9.01/mg

range $0.07–$40.00/mg

Sellers

65

from $0.00

45-day trend

-5.2%

vs 45-day avg $/mg

59 of 65 sellers have a current price· 37 stale listings hidden (not seen in 7 days)

Prices observed from public storefronts (last 24h), normalized to $/mg. "Evidence" is Merit's 0–100 Merit Score, derived only from observable verification evidence (methodology on /about); "Purity" is the latest independent COA. Some buy links are affiliate links — Merit may earn a commission at no extra cost to you, and where a vendor offers one, the code shown gets you a discount at their checkout. Affiliate status never affects price data, ranking, or the Merit Score (full policy on /disclosure). Research use only.

Independent evidence

COAs for Thymosin Alpha-1

106 third-party tests across 23 vendors. Each card links to the full report.

All 106 COAs for Thymosin Alpha-1 →
Measured purity 98.9%–100.0% across 76 COAs
Measured purity over time
Aggregated · 3rd-party listing
99.47 %
Jul 2026
ILS Labs Strong

For

Thymosin Alpha-1

by NG Peptide· batch TA1-05

Aggregated · 3rd-party listing
99.65 %
Jun 2026
Janoshik Analytical Limited

For

Thymosin Alpha-1

by EZ Peptides· batch EZP-TA11006052026-04

Aggregated · 3rd-party listing
99.56 %
Jun 2026
Janoshik Analytical Limited

For

Thymosin Alpha-1

by Verified Peptides· batch TA05260910H

Aggregated · 3rd-party listing
99.57 %
May 2026
Janoshik Analytical Limited · HPLC

For

Thymosin Alpha-1

by Skye Peptides· batch TA126-10-001

Aggregated · 3rd-party listing
99.68 %
May 2026
Freedom Diagnostics Moderate

For

Thymosin Alpha-1

by Real Peptides· batch Black Cap

Aggregated · 3rd-party listing
99.32 %
Apr 2026
Horizon Analytical

For

Thymosin Alpha-1

by Pepsgpt· batch P-1947064-P

Aggregated · 3rd-party listing
98.89 %
Apr 2026
ILS Labs Strong

For

Thymosin Alpha-1

by Riptide Wellness· batch RWTA1-10-1003

✓ Vendor-published
99.98 %
Apr 2026
Kovera Labs

For

Thymosin alpha-1

by Ion Peptide· batch TA110-04202026

COA on file
Aggregated · 3rd-party listing
99.58 %
Apr 2026
Freedom Diagnostics Moderate · HPLC

For

Thymosin Alpha-1

by Peptide Supply Co.· batch TA1004132026

Aggregated · 3rd-party listing
99.00 %
Apr 2026
Ethos Analytics Strong · HPLC

For

Thymosin Alpha-1

by OROS Research· batch OR-LPTA5-326-B1

Aggregated · 3rd-party listing
99.81 %
Apr 2026
Janoshik Analytical Limited · HPLC

For

Thymosin

by Verified Peptides· batch cmojb57q300trkirxximley58

Aggregated · 3rd-party listing
99.91 %
Apr 2026
Biogenica Labs · HPLC

For

Thymosin Alpha-1

by Amino Club· batch THA0001

Aggregated · 3rd-party listing
99.97 %
Mar 2026
Kovera Labs

For

Thymosin alpha-1

by Ion Peptide· batch TA110-03232026

✓ Vendor-published
99.97 %
Mar 2026
Kovera Labs

For

Thymosin alpha-1

by Ion Peptide· batch TA110-03232026

COA on file
Aggregated · 3rd-party listing
99.75 %
Mar 2026
Janoshik Analytical Limited · HPLC

For

Thymosin Alpha-1

by Profound Aminos· batch cmojb89io01hzkirx1zv5axqw

Aggregated · 3rd-party listing
99.39 %
Mar 2026
Janoshik Analytical Limited · HPLC

For

Thymosin Alpha-1

by Verified Peptides· batch TA032608106

Aggregated · 3rd-party listing
99.95 %
Feb 2026
Kovera Labs · HPLC

For

Thymosin Alpha-1

by Peptide Partners· batch TA202602

✓ Vendor-published
99.95 %
Feb 2026
Kovera Labs

For

Thymosin alpha-1

by Peptide Partners· batch TA202602

COA on file
✓ Vendor-published
99.80 %
Feb 2026
Analytical Formulations, Inc.

For

Thymosin Alpha-1

by Ion Peptide· batch TA110-02122026

COA on file
Aggregated · 3rd-party listing
99.68 %
Feb 2026
Kovera Labs · HPLC

For

Thymosin Alpha-1

by Glacier Aminos· batch TA10GA-03

Aggregated · 3rd-party listing
99.51 %
Feb 2026
Freedom Diagnostics Moderate · HPLC

For

Thymosin Alpha-1

by Crush Research· batch CR-TAT10-0212-1

Aggregated · 3rd-party listing
99.80 %
Feb 2026
Analytical Formulations, Inc.

For

Thymosin Alpha-1

by Ion Peptide· batch TA110-02122026

Aggregated · 3rd-party listing
99.44 %
Feb 2026
Freedom Diagnostics Moderate · HPLC

For

Thymosin Alpha-1

by Peptide Supply Co.· batch PSCTA110001

Aggregated · 3rd-party listing
99.83 %
Feb 2026
BioRegen Moderate · HPLC

For

Thymoген

by BioLongevity Labs· batch 44-3-46035

Research depth

20 citations indexed for Thymosin Alpha-1

All research on Thymosin Alpha-1 →

Study · 2026

Thymosin Alpha-1 Restores Chemotherapy-Induced Antitumor Immunity by Chaperoning a MicroRNA Ligand of TLR7 in Dendritic Cells

Chemotherapy induces cancer cell apoptosis and the release of apoptotic bodies (ABs) that are poorly immunogenic or immunosuppressive, creating a major barrier to the success of co-administered or second-line immunotherapies.

Study · 2026

A Case Report of a Multisystemic Immune-Related Adverse Event Caused by Sintilimab in Combination With Thymosin Alpha-1

To report a case of a nasopharyngeal carcinoma patient who developed multisystem immune-related adverse events (irAEs) after treatment with sintilimab (PD-1 inhibitor) in combination with thymosin alpha-1 (Tα1). The patient presents with high fever, rash, interstitial pulmonary edema, and multiple organ failure.

review · 2025

Aging and Thymosin Alpha-1

Aging is characterized by immune decline, mainly due to thymic involution-the age-related shrinkage of the thymus gland. This leads to reduced T-cell production, chronic inflammation, and increased susceptibility to age-related diseases.

Study · 2025

The Immunomodulatory Activity of Thymosin Alpha 1 on Tumor Cell Lines and Distinct Immune Cell Subsets

Background The immune-balancing role of thymosin alpha 1 (Tα1) is well-recognized in contexts of immune dysregulation. Within the anti-tumor context, Tα1 demonstrated to act as an immune-enhancer, with potential roles in immunotherapy-based treatments.

meta-analysis · 2025

Thymosin alpha 1 alleviates inflammation and prevents infection in patients with severe acute pancreatitis through immune regulation: a systematic review and meta-analysis

Background Immune and inflammatory disorders are part of the complex pathophysiological processes that exacerbate severe acute pancreatitis (SAP) and subsequent infection.

Study · 2025

The efficacy and safety of thymosin alpha-1 combined with lenvatinib plus sintilimab in unresectable hepatocellular carcinoma: a retrospective study

To validate the efficacy and safety of thymosin α-1 combined with lenvatinib plus sintilimab in the treatment of unresectable hepatocellular carcinoma.