BPC-157 vs TB-500: Structure, Origin and the Research Literature
BPC-157 and TB-500 are often named together, but they are unrelated molecules with different origins and different bodies of research. This guide compares what they are and what has been studied. It does not compare uses or outcomes.
Research use only. Not for human consumption. Not evaluated by Health Canada. This guide covers specifications, storage and documentation. It gives no dosing or usage guidance.
In short.
- Different molecules. BPC-157 is a 15-amino-acid peptide based on a sequence from gastric juice. TB-500 is a synthetic peptide based on thymosin β4, a 43-amino-acid actin-binding protein.
- Different literature. BPC-157 research is mostly rat studies of tendon, ligament and muscle injury. TB-500 has little direct research; most work is on the full thymosin β4 protein or on its actin-binding motif in cell assays.
- Thin human data for both. A 2025 systematic review found one clinical study of BPC-157 among 36. We found no published human trials of TB-500 itself.
Side by side.
| BPC-157 | TB-500 | |
|---|---|---|
| Origin | Synthetic; sequence derived from a peptide described in gastric juice | Synthetic; based on thymosin β4 |
| Amino acids | 15 | See COA identity result |
| Sequence | GEPPPGKPADDAGLV | See COA identity result |
| Molecular weight | 1419.5 g/mol | See COA identity result |
| Parent molecule | Described as a partial sequence of a human gastric juice protein called BPC | Thymosin β4, 43 amino acids, about 4,963 g/mol |
| Main research themes | Tendon, ligament and muscle injury models; angiogenesis and nitric oxide signalling | Actin binding and cell migration; angiogenesis assays. Parent protein studied in rat wound and mouse heart models |
| Evidence type | Mostly preclinical (rat models, cell culture); one clinical study in a 2025 systematic review | In vitro studies of the fragment; analytical and doping-detection studies; animal studies of the parent protein |
Some analytical studies, such as a 2012 characterization of the TB-500 fragment, define TB-500 as a short acetylated fragment of thymosin β4, but the name is not used consistently across the market. That is why the table points to the COA: the identity result for your lot confirms the molecule in the vial.
Origin and structure.
BPC-157 stands for "body protection compound". The literature describes it as a stable pentadecapeptide, meaning a chain of 15 amino acids, with the sequence GEPPPGKPADDAGLV. The group that first described it calls it a partial sequence of a human gastric juice protein named BPC, and reports that it stays stable in human gastric juice. The synthetic peptide sold for research is that 15-residue sequence on its own.
TB-500 is the name used for a synthetic peptide based on thymosin β4. Thymosin β4 is a 43-amino-acid protein found in most vertebrate cells, where it is the main protein that binds and holds single actin molecules. In thymosin β4, residues 17 to 22 form the motif that contacts actin. Analytical studies of TB-500 products described an acetylated fragment covering that region.
So the two differ at the most basic level: they come from unrelated parent molecules.
What preclinical research has studied.
BPC-157.
Most BPC-157 papers use rats. Examples:
- Rat Achilles tendon. In a 2003 rat Achilles tendon study, Staresinic and colleagues transected the Achilles tendon in rats and measured biomechanical, functional and microscopic outcomes over 14 days. The same paper included cultured tendon cells (tendocytes) in vitro.
- Rat medial collateral ligament. Cerovecki and colleagues studied surgically transected knee ligaments in rats over 90 days.
- Vascular models. Hsieh and colleagues used a chick chorioallantoic membrane assay, a rat hind-limb ischemia model and human endothelial cells in culture to look at VEGFR2 signalling. A later paper from the same group used isolated rat aorta to study nitric oxide signalling.
A 2025 systematic review of the orthopaedic literature screened 544 articles and included 36 studies. Of those, 35 were preclinical. A 2026 review covers tendon, ligament and muscle models in more detail.
TB-500.
Direct research on TB-500 itself is limited:
- Cell and tissue assays. In a 2003 study of thymosin β4's actin-binding site, Philp and colleagues found that a short actin-binding motif of thymosin β4 matched the full protein's activity in human endothelial cell migration and chick aortic arch sprouting assays.
- Analytical studies. Two 2012 papers characterized TB-500 so it could be detected in doping control, including in horses. These are detection methods, not studies of effect.
Most of the related literature is on full-length thymosin β4, not the fragment:
- Rat skin wound. Malinda and colleagues studied thymosin β4 in a rat full-thickness wound model.
- Mouse heart. Smart and colleagues studied thymosin β4 in coronary vessel development and adult epicardial progenitor cells in mice. Bock-Marquette and colleagues review later mouse heart work.
Findings on full-length thymosin β4 cannot be assumed to carry over to a shorter synthetic fragment. They are different molecules.
Where the literature is thin.
Neither compound has meaningful human trial data.
For BPC-157, the 2025 systematic review found one clinical study among 36 included studies: a retrospective study of 12 patients. It found no clinical safety data. Since that review's search window closed, a pilot safety study in two participants has been published. The originating research group has reported phase II trials in ulcerative colitis under the code PL 14736, but we did not locate full published results, and we found no published randomized controlled trials in the literature we reviewed. The 2025 review notes BPC-157 has no US FDA approval.
For TB-500, we found no published human trials of TB-500 itself. A 2012 review describes clinical trials of full-length thymosin β4, a different molecule.
The two-vial stack.
Vitaliti also sells BPC-157 and TB-500 together as the BPC + TB Stack. It ships as two separate vials, one of each compound, each labelled with its own lot code. It is not a blend. The COA for each vial's lot is available by email at contact@vitalitipeptide.com.