TB-500 is a synthetic short fragment of thymosin beta-4, a protein made of 43 amino acids. The fragment covers the actin-binding part of the molecule and is meant to support cell migration and the formation of blood vessels. BPC-157 is an entirely different peptide: 15 amino acids, based on a protein from gastric juice.
Both peptides have sparse human data, both are banned in sport, and neither can be bought legally from a pharmacy as a medicine. This article explains how TB-500 differs from BPC-157. The wider context is covered in our pillar article on how recovery peptides work.
What is TB-500?
TB-500 is a laboratory-made peptide corresponding to the actin-binding part of thymosin beta-4, described by the sequence Ac-LKKTETQ. Thymosin beta-4 is a natural protein present in many tissues. TB-500 is not that whole molecule, only a short section of it, and it is sold as research material.
How is TB-500 supposed to work?
The proposed mechanism rests on binding free, globular actin and blocking its assembly into filaments. This is meant to ease cell movement, tissue rebuilding and the formation of new blood vessels. Because thymosin beta-4 occurs throughout the body, TB-500 is studied for systemic effects rather than local repair alone.
How does TB-500 differ from BPC-157?
| Feature | TB-500 | BPC-157 |
|---|---|---|
| Origin | fragment of thymosin beta-4 (a 43 amino acid protein) | fragment of a protein from gastric juice |
| Structure | short fragment of a larger protein | standalone peptide of 15 amino acids |
| Described action | studied as systemic | described rather as local |
| Human data | no completed efficacy trials for the fragment | one small observational study |
| Status in sport | prohibited at all times (WADA, category S2) | prohibited at all times |
The difference that matters most to a reader is not the mechanism but the evidence. For neither peptide are there large clinical trials confirming efficacy in human injuries.
What do human studies of TB-500 show?
For the TB-500 fragment itself, no completed efficacy trials in humans had been published as of April 2026. Clinical data do exist for full thymosin beta-4, but they concern ophthalmology: eye drops tested in phase 3, not an injectable fragment in musculoskeletal use.
The situation for BPC-157 is similarly thin. It comes down to one small observational study, described in the separate article on what BPC-157 is and what the research shows.
Is TB-500 legal?
TB-500 is not a registered medicine. The United States Food and Drug Administration placed it in category 2 of the 503A list, barred from pharmacy compounding, so it cannot be obtained legally through a pharmacy in the United States. It also appears on the World Anti-Doping Agency list in category S2 and is prohibited in sport at all times.
In our shop TB-500 appears only as research material: TB-500 10 mg and a blend with BPC-157. The cart and the checkout are in English and prices are shown in Polish zloty.
Frequently asked questions
Is TB-500 the same as thymosin beta-4?
It is not. TB-500 is a short fragment of it, covering the actin-binding part. Full thymosin beta-4 has 43 amino acids.
How does the action of TB-500 differ from BPC-157?
TB-500 is studied for effects throughout the body, while BPC-157 is described rather as acting locally. The two have different mechanisms and sparse human data.
Are there human studies of TB-500?
For the TB-500 fragment itself there are no completed efficacy trials in humans. Phase 3 trials were run on full thymosin beta-4 in the form of eye drops.
Can TB-500 be used in sport?
It cannot. TB-500 is on the World Anti-Doping Agency list in category S2 and is prohibited at all times.
Does combining TB-500 with BPC-157 improve results?
No clinical trial has tested the blend in humans. Ready-made blends are sold, but the evidence for the combination is no stronger than for each peptide separately.
Where this information comes from
The description of TB-500, its sequence, the actin-binding mechanism, the absence of completed human efficacy trials and its status on the FDA 503A list and the World Anti-Doping Agency list come from material published by Superpower, version of 2 August 2026. The data on BPC-157 and its single human study come from a review by inPharmD and from material published by Maryland Orthopedic Specialists. All pages were checked on 31 August 2026.