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TB-500 vial

TB-500 5 mg

Also searched as: tb 500, tb500

$45 In stock

Strength
Ships from

For research use only. Not for human or veterinary use.

Ships from the USA or Canada. Shipping details

TB-500 is a lab-made peptide of seven amino acids (Ac-LKKTETQ) that matches amino acids 17 to 23 of thymosin beta-4, a natural 43-amino-acid protein.1 It is a research compound and is not part of any FDA-approved drug.1 Each vial holds 5 mg of TB-500 as a powder for reconstitution in the lab.

Specifications

SequenceAc-Leu-Lys-Lys-Thr-Glu-Thr-Gln-OH (one-letter code: Ac-LKKTETQ)12
Length7 amino acids, acetylated at the N-terminus (thymosin beta-4 positions 17 to 23)1
Molecular formulaC38H68N10O14 (free base); acetate salt C38H68N10O14·CH3COOH31
Molar mass889.0 g/mol (free base); 949.1 g/mol (acetate)31
CAS number885340-08-92
PubChem CID627076623
Solubility50 mg per 1 mL of water (vendor data cited by FDA)1
FormPowder for reconstitution1
Vial contents5 mg per vial
Strength5 mg
Ships fromUSA, Canada
CategoryHealing and Recovery Peptides
StorageVendor data cited by FDA keep sealed TB-500 free base powder away from moisture and light for up to 1 year at -20°C or 2 years at -80°C.1 For the acetate form, the sources FDA cites give 2 to 8°C or below -15°C, so a -20°C freezer meets the figures for both forms.1

Supplies for TB-500

Bulk and wholesale orders

Labs that need TB-500 in larger quantities can apply for a wholesale account. Terms are confirmed on application.

Wholesale detailsApply for a wholesale account

Questions about TB-500

About TB-500

TB-500 is a short synthetic peptide: seven amino acids, the first one (leucine) carrying an acetyl cap.1 Its sequence matches positions 17 to 23 of thymosin beta-4, a 43-amino-acid protein originally isolated from calf thymus.1 That stretch contains LKKTET, the part of thymosin beta-4 that binds actin, a protein of the cell skeleton.1

The name is informal. FDA notes it is not an official drug name, and it has found different salts and even different active molecules sold under it.1 FDA also says TB-500 and thymosin beta-4 are different substances, though several websites use the names interchangeably.1 Molar mass tells them apart: 889.0 g/mol for TB-500 and about 4963 g/mol for thymosin beta-4.34 For testing documents, see lab results.

This page lists TB-500 for sale as a 5 mg research vial in the healing and recovery peptides category. The current TB-500 price and stock appear in the selector. For a plain-language overview, read What is TB-500?

Research highlights

  • In an exploratory 2026 study of 32 rats after Achilles tendon repair, the 8 given TB-500 for 4 weeks had better tissue scores (p = 0.016) and stronger tendons than controls.5
  • In the same study, combining TB-500 with BPC-157 gave no extra benefit over either peptide alone.5
  • In cultured fibroblasts, TB-500 itself showed no significant wound-healing activity; of the compounds tested, only its breakdown product Ac-LKKTE did.6
  • In horses given one injection under the skin, plasma levels peaked 1 to 2 hours later and could no longer be quantified after 6 to 10 hours.17
  • A 2012 analysis of a TB-500 product suspected of doping use identified Ac-LKKTETQ in it by mass spectrometry.8
  • FDA's 2026 review found no published article in which TB-500 was given to people.1 A 2026 report on 3 patients used it in an uncontrolled multi-drug mix.9
  • FDA found no animal or lab toxicity studies of TB-500, including none on reproduction or cancer.1

Regulatory status

TB-500 is not FDA-approved, has no USP or National Formulary monograph, and is not part of any approved drug.1 FDA staff proposed not adding TB-500 or its acetate to the 503A Bulks List for pharmacy compounding.1 In July 2026 an advisory committee voted 8 to 6, with 1 abstention, to recommend adding both.10 The vote is nonbinding, and FDA still has to act.10

In a 2023 warning letter, FDA told an online seller that its "TB-500" products were unapproved new drugs, not generally recognized as safe and effective.11 Despite "research purpose only" labeling, FDA said evidence from the seller's website showed the products were intended for human use.11 WADA's 2026 Prohibited List bans TB-500 in sport at all times, under class S2.3.12

Handling and storage

TB-500 is sold as a powder that is reconstituted (dissolved) before lab use.1 Vendor data cited by FDA report that the free base dissolves in water at 50 mg per mL, so solubility does not limit a 5 mg vial.1 FDA cautions that peptides like TB-500 can aggregate or degrade with changes in pH, heat, concentration, impurities or added ingredients.1

The supplies listed with this vial are bacteriostatic water, a 3 mL Luer-Lok syringe, an 18G 1-inch needle, insulin syringes and alcohol swabs. The TB-500 reconstitution guide covers lab steps, concentration math and storage after mixing. The reconstitution calculator does the arithmetic.

Researchers can buy TB-500 online here by the vial, or apply for wholesale supply. Browse all research peptides.

Frequently asked questions

Where can I buy TB500 peptide?

You can buy TB-500 on this page as a 5 mg research vial from D2C Peptides. Stock and ship-from options show in the selector, and delivery details are on the shipping page. The vial is sold for laboratory research use only. No TB-500 product is FDA-approved for use in people.1

What is the price of TB-500 peptide?

The 5 mg vial is $45. The selector on this page shows the current price for each ship-from option and whether it is in stock. Delivery options and costs are on the shipping page. Labs that need larger quantities can apply for a wholesale account, with terms confirmed on application.

Which is the best TB 500?

No TB-500 product is FDA-approved, so no regulator has verified a best version.1 A representative certificate of analysis that FDA found covered only appearance, identity and purity; it did not test assay (active content), impurities, bacterial endotoxins or aggregates.1 A stronger certificate covers those tests and reports a measured mass near 889 g/mol, the value for TB-500.3 See lab results for testing information.

What supplies are used with a TB-500 vial?

The supplies listed with this vial are bacteriostatic water, a 3 mL Luer-Lok syringe, an 18G 1-inch needle, insulin syringes and alcohol swabs. The TB-500 reconstitution guide shows where each one fits in the lab steps, and the reconstitution calculator works out the concentration.

How should TB-500 be stored when it arrives?

Put the sealed vial in a -20°C freezer, away from light and moisture, when it arrives. Vendor data cited by FDA give the free base powder up to 1 year at -20°C, and the sources FDA cites for the acetate give 2 to 8°C or below -15°C.1 No source used here gives a safe time at room temperature. Once mixed, the same vendor data allow only 1 month at -20°C.1 See the TB-500 reconstitution guide.

Written by D2C Peptides Editorial Team.

Pending qualified review.

Updated .

Sources

  1. FDA Briefing Document, Pharmacy Compounding Advisory Committee, July 23-24, 2026: TB-500-Related Bulk Drug Substances (TB-500 (Free Base) and TB-500 acetate). U.S. Food and Drug Administration, 2026.
  2. PubChem Compound CID 62707662: synonyms. PubChem, National Center for Biotechnology Information (NIH), 2026.
  3. PubChem Compound CID 62707662 (TB-500): computed properties. PubChem, National Center for Biotechnology Information (NIH), 2026.
  4. PubChem Compound CID 45382195 (Thymosin Beta 4): computed properties. PubChem, National Center for Biotechnology Information (NIH), 2026.
  5. Effects of BPC-157 and TB-500 on Achilles tendon healing in rats: A histopathological and biomechanical study (Biçer et al., PMID 42542926). Joint Diseases and Related Surgery, 2026.
  6. Simultaneous quantification of TB-500 and its metabolites in in-vitro experiments and rats by UHPLC-Q-Exactive orbitrap MS/MS and their screening by wound healing activities in-vitro (Rahaman et al., PMID 38382158). Journal of Chromatography B, 2024.
  7. Doping control analysis of TB-500, a synthetic version of an active region of thymosin β4, in equine urine and plasma by liquid chromatography-mass spectrometry (Ho et al., PMID 23084823). Journal of Chromatography A, 2012.
  8. Synthesis and characterization of the N-terminal acetylated 17-23 fragment of thymosin beta 4 identified in TB-500, a product suspected to possess doping potential (Esposito et al., PMID 22962027). Drug Testing and Analysis, 2012.
  9. Case Report: Regenerative peptides for Inferior alveolar nerve injury: a narrative review with hypothesis-generating three clinical cases (full text, PMC13661421). Frontiers in Oral Health (via PubMed Central), 2026.
  10. FDA committee recommends looser restrictions for several peptides. Healio, 2026.
  11. Warning Letter: Warrior Labz SARMS (MARCS-CMS 655280), June 12, 2023. U.S. Food and Drug Administration, 2023.
  12. World Anti-Doping Code International Standard: Prohibited List 2026. World Anti-Doping Agency (PDF hosted by the International Testing Agency), 2025.
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