Research material and lot documents
TB-500 and BPC-157 are different peptides: BPC-157 has 15 amino acids, and TB-500 is a seven-amino-acid acetylated fragment of the 43-amino-acid protein thymosin beta-4. The two together make up the pair sold as the Wolverine stack, described on the Wolverine peptide page.
The two columns below use the same order: names, sequence, formula and weight, reference records, origin of the sequence and human records.
Names: BPC-157, also known as Bepecin or PL-14736.
Sequence: 15 residues, Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val.
Formula and weight: C62H98N16O22, 1419.5 g/mol, as PubChem lists them for the reference compound.
Reference records: PubChem CID 9941957 and FDA UNII 8ED8NXK95P.
Origin of the sequence: a partial sequence of a protein from human gastric juice, as the 2011 authors describe it.
Human records: a 2021 chart review of 17 patients and a 2025 pilot study of two adults, both linked below.
Listing: BPC-157 and the pair in Curo's recovery catalog. Single-peptide reading: BPC-157.
Names: TB-500 is a common name. FDA's record calls it the N-terminal acetylated 17-23 fragment of thymosin beta 4.
Sequence: 7 residues, N-acetyl-Leu-Lys-Lys-Thr-Glu-Thr-Gln, written Ac-LKKTETQ.
Formula and weight: C38H68N10O14, 889.0 g/mol, as PubChem lists them for the reference compound.
Reference records: PubChem CID 62707662 and FDA UNII QHK6Z47GTG.
Origin of the sequence: residues 17 to 23 of the 43-residue protein thymosin beta-4.
Human records: FDA's July 2026 briefing says its literature search found no articles on TB-500 in humans.
Listing: TB-500 5 mg listing at Curo. Single-peptide reading: TB-500.
Sources for the columns: PubChem BPC-157 record, FDA BPC-157 identity record, PubChem TB-500 fragment record, FDA TB-500 fragment identity record, FDA BPC-157 briefing document, FDA TB-500 briefing document and 2011 BPC-157 rat tendon-cell study.
No. Thymosin beta-4 is a 43-residue protein, and TB-500 reproduces residues 17 to 23 of it with an acetyl group at the start. FDA lists them under different identifiers, UNII 549LM7U24W for thymosin beta-4 and UNII QHK6Z47GTG for TB-500. Sources: FDA thymosin beta-4 identity record, FDA TB-500 fragment identity record and UniProt thymosin beta-4 entry P62328.
Human trials registered under the protein name are not trials of the fragment. One example is a phase 3 trial of an eye solution that contains thymosin beta-4. Source: ClinicalTrials.gov record NCT02974907, ReGenTree.
FDA's July 2026 TB-500 briefing says "TB-500 is a common name and not a United States Adopted Name (USAN)." It adds that FDA "has encountered multiple salts, and derivatives, including different active moieties, sold commercially under the same common name." A paper or a label that says TB-500 needs a check against the molecule it describes. Source: FDA briefing document on TB-500, July 23-24, 2026.
Each result below belongs to the molecule and the model its paper names.
The 2011 authors used rat tendon explants and cultured rat tendon fibroblasts. They reported faster outgrowth, more cell migration and better cell survival under oxidative stress, and they found no direct effect on proliferation. Source: 2011 BPC-157 rat tendon-cell study, PMID 21030672. A 2021 chart review of 17 patients at one clinic reported improvement in most of the 16 patients reached, and its abstract describes no comparison group. Source: 2021 knee-pain chart review, PMID 34324435. A 2025 pilot study of two adults reported no measurable effects on the tested biomarkers and no reported side effects. Source: 2025 BPC-157 pilot study of two adults, PMID 40131143.
A 2003 paper used human umbilical vein endothelial cells and chick aortic arches. Its authors reported that a seven-amino-acid actin-binding motif of thymosin beta-4 was essential for the angiogenic activity they measured. Source: 2003 thymosin beta-4 angiogenesis study, PMID 14500546. A second 2003 paper used mouse wound models. Its authors reported that thymosin beta-4 accelerated wound repair in diabetic and aged mice, and that the seven-amino-acid peptide LKKTETQ promoted repair in aged mice comparably to the parent protein. Source: 2003 thymosin beta-4 mouse wound study, PMID 12581423.
FDA's TB-500 briefing notes that "the pharmacological profile of the non-acetylated heptapeptide LKKTETQ cannot be directly extrapolated to the N-acetylated heptapeptide TB-500." A 2024 study of TB-500 and its metabolites in human serum, enzyme systems and rat samples reported significant wound-assay activity only for the metabolite Ac-LKKTE. Source: 2024 TB-500 metabolite study, PMID 38382158.
One experiment placed both in the same rat tendon model, with a combination group. The BPC-157 and TB-500 together page gives its results and limits. The searches behind that page found no human comparison of the two peptides.