TB-500 is a synthetic fragment of thymosin beta-4 (Tβ4), a naturally occurring 43-amino-acid peptide found throughout human tissues. TB-500 contains the active healing region (sequence: Ac-LKKTETQ, MW ~889 g/mol) responsible for cell migration and tissue repair. It has a handful of human RCTs for wound healing and dry eye, plus a dedicated safety trial in 40 healthy adults showing minimal adverse effects. Despite this, it remains unapproved for human therapeutic use in all major markets and is banned by WADA and in horse racing.
42 vendors tracked by PeptideAtlas list TB-500, priced from $18.00 to $165. The lowest price per milligram is $1.95/mg at Archer Peptides (20MG). 32 independent Janoshik purity tests cover TB-500 across 26 vendors. Results range from 98.5% to 100.0%.
Category: Healing & Recovery. Evidence rating: D (animal/preclinical only).
Clinical status: Research-only / Veterinary use in some jurisdictions. Limited human RCTs completed.
TB-500 works primarily through actin sequestration — it binds to G-actin monomers, preventing premature polymerization, which allows repair cells to migrate rapidly to injured areas. Research in Trends in Cell Biology showed Tβ4 acts as a "battery for cell movement." It promotes angiogenesis by…
Research base: 10 registered clinical trials and 44 indexed publications reference TB-500.
Safety considerations: A safety-focused RCT in 40 healthy adults (2010) was designed expressly to assess safety and found minimal adverse effects with synthetic thymosin-beta 4; No significant safety concerns in published human studies to date; TB-500 administration has produced minimal side effects in animal and human studies alike; Common anecdotal side effects: injection site pain/redness, lightheadedness, mild headache, nausea, fatigue.
Reviewed by the PeptideAtlas Editorial Team.
| Amino-acid sequence | Ac-LKKTETQ (active heptapeptide region of thymosin beta-4) |
|---|---|
| Molecular weight | ~889 g/mol |
| Half-life | <2 hours plasma half-life; tissue effects persist 2–3 days |
| Bioavailability | Subcutaneous injection; rapid systemic distribution |
| Production method | synthetic |
| Anti-doping status | Prohibited in sport (WADA) |
| US regulatory status | Not FDA-approved. Removed from Category 2 on April 15, 2026. PCAC review pending July 2026. Previously classified as Category 2 since September 2023. WADA-banned (S2 growth factor). |
| Vendor | Size | Price | Price per mg |
|---|---|---|---|
| Archer Peptides | 20MG | $39.00 | $1.95/mg |
| Sigma Peptides | 10MG | $34.99 | $3.50/mg |
| Great Lakes Peptides | 5mg | $18.00 | $3.60/mg |
| Evolve BioPep | 10mg | $40.00 | $4.00/mg |
| Legendary Peptides | 10mg | $42.00 | $4.20/mg |
| All Peptides USA | 10MG | $44.00 | $4.40/mg |
| PureRx Peptides | 10mg | $45.00 | $4.50/mg |
| Peptide Labs | 10mg | $49.99 | $5.00/mg |
| Choice Peps | 5MG | $25.00 | $5.00/mg |
| Athena Peptides | 10MG | $54.00 | $5.40/mg |
| Astra Peptides | 10MG | $56.99 | $5.70/mg |
| Blue Line Research | 10mg | $59.00 | $5.90/mg |
| Atomix Research | 5 mg | $29.99 | $6.00/mg |
| Orbitrex Peptides | 10mg | $59.99 | $6.00/mg |
| Lucky Link Peptides | 10MG | $60.00 | $6.00/mg |
| AminoVault | 10mg | $63.00 | $6.30/mg |
| Great Northern Peptides | 10mg | $65.00 | $6.50/mg |
| The Peptide Labs | 10MG | $65.00 | $6.50/mg |
| NUPEPS Peptides | 10mg | $66.00 | $6.60/mg |
| Petratide Science | 5mg | $34.95 | $6.99/mg |
| Pepix Labs | 10MG | $70.00 | $7.00/mg |
| Growth Guys | 10mg | $70.00 | $7.00/mg |
| Red Fox Peptides | 10 mg | $70.00 | $7.00/mg |
| Wholesale Peptide | 5mg | $37.39 | $7.48/mg |
| Protide Health | 10mg | $75.00 | $7.50/mg |
| Vendor | Best tested purity |
|---|---|
| MOB Peptides | 100.0% |
| Idenex | 99.9% |
| Peptira | 99.9% |
| Amino Alchemy | 99.9% |
| Hangzhou Mandy Biotechnology | 99.8% |
| Pink Pony Peptides | 99.8% |
| lunapharm.diag | 99.8% |
| Heman Peptide HM | 99.7% |
| PACIFIC WAVE PEPTIDES | 99.6% |
| Inno Peptides | 99.6% |
| XL Peptides | 99.6% |
| Optima Chemical Supply, Inc. | 99.5% |
| XTP | 99.5% |
| Peptide Gurus | 99.5% |
| [email protected] | 99.4% |
| [email protected] | 99.3% |
| Cocer Peptides | 99.3% |
| Freedom Health | 99.3% |
| newwavepeptides.co.uk | 99.3% |
| Kensingtonlabs.co | 99.2% |
| Homopeptide | 99.2% |
| Amino Pure Canada | 99.2% |
| Imperial Peptides | 99.1% |
| cellpept | 99.1% |
| Panda Peptides LLC | 98.5% |
Related peptides: BPC-157, Thymosin Beta-4, Larazotide.
TB-500 is a synthetic fragment of thymosin beta-4, a 43-amino-acid peptide found naturally in virtually all human and animal cells. TB-500 contains a shorter chain focused on the healing and tissue repair active region (the first 15 amino acids contain the cell protection potential). They are structurally and functionally very similar, and the names are often used interchangeably.
This combination (sometimes called the "Wolverine Stack") is discussed anecdotally. TB-500 works systemically through actin sequestration and angiogenesis, while BPC-157 targets localized tissue repair through different pathways. There is no controlled human research on the combination. TB-500 can also be combined with IGF-1 or GHK-Cu.
A loading phase of 4-8 mg per week (split into 2-3 smaller doses) for the first 4 weeks is commonly discussed, followed by a maintenance phase of 2-4 mg bi-weekly. Intramuscular injection may show results earlier than subcutaneous. The most dramatic reduction in inflammation is typically during the loading phase.
Yes. TB-500 and all thymosin beta-4 derivatives are banned by WADA as class S2 growth factors, prohibited at all times (in and out of competition). It is also banned in horse racing.
Research shows contrasting results. One study reported TB-500 may slow colon cancer growth by decreasing survival signal activity. However, another study indicated potential negative effects in other cancer types. Given these conflicting results, individuals with cancer history should avoid TB-500.
Vendors with independent lab tests for it: Freedom Health, Kensingtonlabs.co, Pink Pony Peptides, Optima Chemical Supplies Inc, AstropeptidesUSA, Idenex, MOB Peptides.
Vendors stocking it: Direct Peptides UK, LimitlessBioChem, Polar Peptides, Risynth Bio, NUPEPS Peptides, Eternal Peptides, M-Peptides, Amino Lair, Reta-Peptide, Evolve BioPep, Wuhan Wansheng Biotechnology, Wolverine Peptides, Homopeptide, Pepix Labs, All Peptides USA, DH Peps, Sigma Peptides, Biomax Research, NovaPeptide, Ultima Pharmaceuticals, Prime Lab Peptides, Pacific Peptide, Lab Rat Peptide, Choice Peps, Wholesale Peptide, Compound Purity, Peplogix Peptides, Petratide Science, Modern Peptides, Blue Line Research, SupraChems, Legendary Peptides, Lab Trust Peptides, Verasynlabs, Bioscience Peptides, Ds Peptides, BioPure Peptides, Astra Peptides, US Chem Labs, Archer Peptides.
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