BPC-157 vs TB-500 — How the Two Compounds Compare
BPC-157 and TB-500 are the two most-discussed research peptides, and they are often mentioned together. They are chemically unrelated and come from entirely different parent molecules. This page sets out the factual differences for researchers comparing the two.
| BPC-157 | TB-500 | |
|---|---|---|
| Origin | Fragment of a protein in gastric juice | Fragment of thymosin beta-4 (Tβ4) |
| Type | 15-amino-acid peptide (pentadecapeptide) | 7-amino-acid acetylated fragment |
| Sequence | GEPPPGKPADDAGLV | Ac-LKKTETQ (Tβ4 17–23) |
| CAS number | 137525-51-0 | 885340-08-9 |
| Molecular weight | ~1419.6 g/mol | ~889.0 g/mol |
| Research focus | GI tissue, tendon/ligament & angiogenesis models | Actin dynamics & cell-migration models |
| Index Peptides formats | 5mg, 10mg + blends | 10mg + blends |
They come from different parent molecules
BPC-157 (Body Protection Compound 157) is a synthetic 15-amino-acid peptide whose sequence is a partial fragment of a protective protein originally identified in human gastric juice. TB-500 is a synthetic 7-amino-acid fragment (the actin-binding region, LKKTETQ) of thymosin beta-4, a 43-amino-acid protein found in most mammalian cells. The two are not related and are not interchangeable.
Different chemistry
BPC-157 (CAS 137525-51-0, ~1419.6 g/mol) is roughly 60% larger than the TB-500 fragment (CAS 885340-08-9, ~889.0 g/mol). Both are supplied as lyophilised powders and both are commonly handled as acetate salts; the exact form is recorded on each batch's certificate of analysis.
Different research literature
BPC-157 appears in preclinical literature concerning gastrointestinal tissue models, tendon and ligament fibroblast cultures, and angiogenesis pathways. The TB-500 fragment is studied specifically as the actin-binding motif of thymosin beta-4, within actin-dynamics and cell-migration research. In both cases the published work is preclinical (rodent and in-vitro); controlled human data are lacking and no conclusions about human effects can be drawn.
Why they are often sold as a blend
Because the two compounds are studied in overlapping tissue-model contexts, they are sometimes co-formulated in a single research vial. Index Peptides lists a BPC-157 + TB-500 blend and a three-way BPC-157 + GHK-Cu + TB-500 blend; each blend is documented with its own batch record and is priced below the combined cost of the separate peptides.
Regulatory status (both)
Neither compound is an approved medicine in any jurisdiction, and both are prohibited in sport by WADA. Index Peptides supplies both strictly for in-vitro laboratory research — not for human or veterinary use of any kind.
Frequently asked questions
Is BPC-157 or TB-500 'better'?
Neither is 'better' — they are different compounds from different parent molecules, studied in different research contexts. Index Peptides supplies both as research materials only and takes no position on any application.
Can they be used together?
They are sometimes co-formulated as a research blend because their literature overlaps. Index Peptides offers documented blends, but supplies all material strictly for in-vitro laboratory research, not for any in-vivo use.
How do I verify the identity of each?
Every released batch of either compound is HPLC purity tested and LC-MS identity confirmed, with the COA on the product page and batch lookup by lot number.
References
Research use only. Not for human or animal consumption.