BPC-157 vs TB-500: evidence, status and structure
A side-by-side look at BPC-157 and TB-500, using the data on each VALREXA profile. Neither comparison is a recommendation.
Key differences
- Both sit at the same evidence level: Preclinical.
- Both have the same U.S. status category: Compounding allowed.
- BPC-157 is about 1.6× heavier than TB-500 (~1,419.5 vs ~889.0 Da).
| BPC-157 | TB-500 | |
| Research class | Repair & Tissue Biology | Repair & Tissue Biology |
| Human evidence | Preclinical | Preclinical |
| U.S. status | Not FDA-approved | Not FDA-approved |
| 2026 compounding decision | Allowed for 503A pharmacies under FDA enforcement discretion (Oct 2026) | Allowed for 503A pharmacies under FDA enforcement discretion (Oct 2026) |
| Amino acids | 15 | 7 (fragment) |
| Molecular weight | ~1,419.5 Da | ~889.0 Da |
| Formula | C₆₂H₉₈N₁₆O₂₂ | Varies by form |
| Sequence | GEPPPGKPADDAGLV | — |
| Research period | 1990s | Thymosin β4 research: 1980s |
| Safety summary | Not FDA-approved for human therapeutic use; long-term safety is unknown. | TB-500 is not FDA-approved as a therapeutic product. |
How they differ
BPC-157 is a 15-amino-acid synthetic peptide modeled on part of a protein reported in human gastric juice. TB-500 is a short synthetic fragment based on the actin-binding region of thymosin beta-4, a natural 43-amino-acid protein. They are often discussed together online, but they come from unrelated parent molecules. Both are graded Preclinical, and both were included in the FDA's October 2026 enforcement-discretion decision for 503A compounding, which is not approval.
What each one is
BPC-157: Synthetic pentadecapeptide investigated for gastrointestinal and tissue biology. Molecular weight, sequence, research history, human evidence and regulatory status.
TB-500: Commercial term often used for thymosin β4 or a fragment; the label does not define one unique molecule. Molecular weight, sequence, research history, human evidence and regulatory status.
Educational reference only. Nothing here is medical advice, a treatment recommendation, or dosing or sourcing guidance. Report an error.