Why do Thymosin Alpha-1 prices vary so much between vendors?

Vial sizes differ, so always compare the same vial size across vendors. Batch testing, stock status, and pack discounts also move the true cost.

How does Peptide Watchdogs verify Thymosin Alpha-1 vendors?

A vendor earns a Verified badge only after independent batch testing (HPLC purity plus mass-spec identity) checks out against its published COA. Verification is never for sale.

Price index / Thymosin Alpha-1

Recovery

Thymosin Alpha-1

Also known as thymalfasin

CAS 62304-98-7 Also sold as Thymalfasin, TA1, Ta-1, Zadaxin

A recovery research peptide. Current market pricing by vial size, and vendor listings as they are verified.

For research use only. Not for human consumption. No health, dosing, or usage claims are made.

What Thymosin Alpha-1 is

Thymosin Alpha-1 (thymalfasin) is a synthetic 28-amino-acid, N-acetylated peptide identical to the N-terminal fragment of the naturally occurring thymic protein prothymosin alpha. In the research literature it is described as an immunomodulator that signals through Toll-like receptors to influence T-cell and dendritic-cell maturation. In the United States it is an unapproved research chemical sold for laboratory research use only.

Type28 amino acids (a linear, N-terminally acetylated octacosapeptide)

Molecular formulaC129H215N33O55

Molecular weight3108.32 g/mol

CAS number62304-98-7

Amino-acid sequenceAc-Ser-Asp-Ala-Ala-Val-Asp-Thr-Ser-Ser-Glu-Ile-Thr-Thr-Lys-Asp-Leu-Lys-Glu-Lys-Lys-Glu-Val-Val-Glu-Glu-Ala-Glu-Asn (N-terminally acetylated; linear, no disulfides)

CategoryRecovery

Regulatory status: Not FDA-approved in the United States, and the FDA has moved to restrict its compounding. It is approved and marketed in roughly 35 countries (as thymalfasin / Zadaxin) for indications such as chronic hepatitis B and C and as an immune adjuvant; those approvals do not apply in the US.

Vial price (low)

$35

Vial price (high)

$110

Vial sizes

5, 10 mg

Vendors listing

—

Verified

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Price by vial size

sourced market ranges · Jul 2026

5 mg vial

$35–$70

10 mg vial

$55–$110

Typical vendor vial prices, Jul 2026. Exact prices load with verified listings.

Compare vendors

vendor prices · lowest first

Vendor	Vial price	Coupon
Simple Peptide	$0.05Best	—	View vendor ›
Precision Research Peptides	$0.13	WATCHDOG20	View vendor ›
Prime Lab Peptides	$0.16	—	View vendor ›
Koi Peptides	$0.18	—	View vendor ›
Protide Health	$0.20	—	View vendor ›
BioInfinity Lab	$0.22	—	View vendor ›
Kaia Peptides	$0.33	—	View vendor ›
BioLongevity Labs	$0.50	—	View vendor ›
Mile High Compounds	$1	—	View vendor ›
PSPeptides	$3.60	—	View vendor ›
Skye Peptides	$8.80	—	View vendor ›

Comparing vial prices. Vial price is what you actually pay — no derived math to get wrong. Just match the vial size across vendors: a 10 mg vial against another 10 mg vial. Sizes for this compound are listed above. Need to plan a reconstitution? Use the calculator.

Where it shows up in research

literature areas · not a health claim

Immune-modulation and immune-support researchAntiviral research (hepatitis and infectious disease)Adjuvant research in oncology and vaccination

These are areas where the compound appears in the scientific literature. Listing a research area is not a health claim and does not indicate any effect you should expect.

Storage & handling

Freeze-dried (lyophilized) vials are typically kept cold and out of direct light.
Once mixed with bacteriostatic water, peptides are generally refrigerated and used within a limited window.
Always follow the storage details on the vendor's COA and vial label.

Planning a reconstitution? Use the calculator — it is math for handling a vial, not dosing.

Looking at this for yourself? Thymosin Alpha-1 is a research compound — whether it is right for a person is a medical question we cannot answer. Talk to a licensed clinician. Everything on this page is for laboratory research use only.

Sources & further reading: PubChem CID 16130571 — thymalfasin identity (NCBI) · Thymosin alpha 1: a comprehensive review (NCBI PMC) · Thymosin alpha 1 review (PubMed 33362999)
How we source this ›

Frequently asked

How much does Thymosin Alpha-1 cost?

About $35–$110 per vial, depending on vial size. Compare the same size across vendors.

Why do Thymosin Alpha-1 prices vary so much?

Vial sizes differ, so always compare the same vial size across vendors. Batch testing, stock, and pack discounts move the true cost too — see what "Verified" means.

How are Thymosin Alpha-1 vendors verified?

A vendor earns a Verified badge only after independent batch testing (HPLC purity + mass-spec identity) checks out against its COA. Verification is never for sale.

Related compounds

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BPC-157 $40+ / vial TB-500 $55+ / vial KPV $35+ / vial ARA-290 $45+ / vial