Research guide

BPC-157 vs TB-500: what the published research shows

BPC-157 and TB-500 are often mentioned together, but they are unrelated molecules with different origins, different research histories and very different amounts of published evidence. This guide compares them side by side, using the published studies listed at the end.

At a glance

What it is

BPC-157: Synthetic 15-amino-acid peptide (pentadecapeptide) derived from a protein in human gastric juice
TB-500: Synthetic 7-amino-acid fragment of thymosin beta-4, a 43-amino-acid protein found in most cells

Sequence

BPC-157: Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val
TB-500: Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln (Ac-LKKTETQ, residues 17–23 of thymosin beta-4)

Molecular formula and weight

BPC-157: C62H98N16O22, 1419.5 g/mol
TB-500: C38H68N10O14, 889.0 g/mol (full thymosin beta-4: 4963 g/mol)

Main research models

BPC-157: Rat injury models; cultured tendon fibroblasts and endothelial cells
TB-500: Mostly full-length thymosin beta-4 in cells, rodents and small eye-drop trials; studies of the TB-500 fragment itself are mainly analytical

Human data

BPC-157: Three small pilot studies (30 people in total), rated very low certainty
TB-500: No published human trials of the TB-500 fragment

Sport (WADA)

BPC-157: Prohibited at all times (S0, non-approved substances) since 2022
TB-500: Prohibited at all times (S2, thymosin beta-4 and its derivatives)

BPC-157 in the research

Almost all BPC-157 research is preclinical. A 2025 systematic review found 36 relevant studies, of which 35 were preclinical and one was clinical. Across rat models it reported improved structural and biomechanical outcomes in muscle, tendon, ligament and bone injuries, and a half-life of under 30 minutes.

Cell studies point to several mechanisms. In rat Achilles tendon fibroblasts, BPC-157 increased cell survival under oxidative stress and increased migration, with dose-dependent activation of FAK and paxillin, but did not directly increase proliferation. A later study found it increased growth hormone receptor expression in the same cells. In endothelial cells and a rat hind-limb ischaemia model, it was linked to increased VEGFR2 expression and activation of the VEGFR2-Akt-eNOS pathway, which is involved in new blood vessel formation.

Human evidence is very limited. A 2026 systematic review found three small studies with 30 participants in total: a retrospective knee-pain study, a retrospective bladder study and a two-person intravenous safety pilot. The authors rated the certainty of evidence as very low. Sport Integrity Australia states that BPC-157 is not approved for human use.

TB-500 in the research

The most important point about TB-500 is that most of the research people cite was done on a different molecule. TB-500 is the name used for a short, acetylated fragment of thymosin beta-4. Doping-control laboratories identified the fragment Ac-LKKTETQ as the active content of products sold as TB-500. The biological studies, however, mostly used full-length thymosin beta-4, which is about five and a half times heavier.

Full-length thymosin beta-4 binds actin, a protein cells use to move and change shape. In a rat wound model, it increased re-epithelialisation by 42% at day 4 and up to 61% at day 7 compared with saline. In mice, it promoted heart muscle cell migration and survival through integrin-linked kinase and Akt signalling. It is also one of the few peptides in this group tested in controlled human trials: a small phase 2 trial of thymosin beta-4 eye drops for severe dry eye reported improvements over the control solution.

Published work on the TB-500 fragment itself is mostly about detection. Racing and anti-doping laboratories have developed methods to detect it and its breakdown products in horse and rat samples. A 2024 study found that, of the fragment and its metabolites, only one metabolite (Ac-LKKTE) showed significant wound-healing activity in a cell assay. There are no published human trials of the fragment.

Why identity testing matters for TB-500

Because "TB-500" is a product name rather than a defined molecule, the label alone does not tell you what is in the vial. A mass-spectrometry result on the certificate of analysis should match the declared molecule: about 889 g/mol for the Ac-LKKTETQ fragment, or about 4963 g/mol for full thymosin beta-4. For BPC-157, the expected mass is about 1419.5 g/mol. Our guide to reading a COA explains how to check this, and our Batch documentation page lists the reports we have published.

Sources

This guide summarises published research for information only. Findings from cell and animal studies do not show that a compound is safe or effective in people. All Nautic Peptides products are supplied strictly for in-vitro laboratory research and are not for human or veterinary use.