BPC-157 and TB-500 are often mentioned together because both appear in preclinical research on tissue models. They are, however, unrelated molecules. This comparison sets out the facts side by side. It is a research summary, not guidance on use.
At a glance
| BPC-157 | TB-500 (Thymosin Beta-4) | |
|---|---|---|
| Length | 15 amino acids | 43 amino acids (full-length thymosin beta-4) |
| Sequence | GEPPPGKPADDAGLV | Ac-SDKPDMAEIEKFDKSKLKKTETQEKNPLPSKETIEQEKQAGES |
| Molecular weight | ≈1419.5 g/mol | ≈4963 g/mol |
| Origin | Synthetic; sequence derived from a protein described in human gastric juice | Thymosin beta-4 is a naturally occurring actin-binding protein found in many cell types |
| Main research themes | Rodent models of tendon, ligament, muscle and gastrointestinal tissue; angiogenesis | Actin regulation, cell migration, wound and tissue models |
| FDA status | Not approved for any use | Not approved for any use |
A note on the name “TB-500”
“TB-500” is a research-market name rather than a formal scientific one. Some products sold under it are full-length thymosin beta-4; others are a short fragment from the protein’s actin-binding region. Always check the sequence and molecular weight on the specification and COA. OxygenLab’s TB-500 is the full-length 43-amino-acid sequence.
How their research differs
BPC-157 research is mostly preclinical and comes largely from a small number of research groups, with many studies in rodent injury models. See our BPC-157 research overview.
Thymosin beta-4 has a broader basic-science literature because it is a native protein involved in actin sequestration, a key process in cell shape and movement. Research covers cell migration, angiogenesis and tissue-repair models.
For both, findings in cell and animal models do not establish effects in humans. Primary literature is searchable on PubMed (BPC-157) and PubMed (thymosin beta-4).
Why they are studied together
Because both appear in tissue-repair research, some laboratories study them in the same experimental models or as combined preparations. OxygenLab offers each individually and as a combined research blend, all third-party tested; see our COA page.
Regulatory status
Neither compound is FDA-approved. Both appear on the World Anti-Doping Agency prohibited list. Confirm current rules in your jurisdiction before starting work.
Frequently asked questions
Are BPC-157 and TB-500 the same thing?
No. They have different sequences, sizes and origins.
Which is larger?
Full-length thymosin beta-4 (43 amino acids, about 4963 g/mol) is roughly three and a half times the mass of BPC-157 (15 amino acids, about 1419.5 g/mol).
Research use only. OxygenLab products are supplied for in-vitro laboratory research and analytical use only. They are not for human or animal use and are not intended to diagnose, treat, cure or prevent any disease. See our Legal & Compliance policy.
Lab tool: Working out solution concentration? Try the free OxygenLab Peptide Calculator — enter vial mass and diluent volume to get mg/mL, µg/mL and molarity.
