BPC-157 and TB-500 account for a large share of research-peptide search volume, and they are almost always searched as a pair. Most published material on them repeats the same summary without checking it.
This page sets out what each compound is chemically, why they are studied in parallel, what the published research has actually established, and where the evidence stops. It contains no dosing information, no reconstitution or administration guidance, and no claims about effects in people.
All material on this site is supplied strictly for in vitro laboratory research.
In short
- BPC-157 is a synthetic 15-amino-acid fragment of a protein found in human gastric juice
- TB-500 is a synthetic 7-amino-acid fragment (Ac-LKKTETQ) of thymosin beta-4, not the whole protein
- They are studied together because their proposed mechanisms do not overlap — angiogenesis and growth factor signalling in one, actin regulation and cell migration in the other
- BPC-157 has a large animal literature and fewer than 30 human subjects across three published studies, none randomised or controlled
- Most human research cited for TB-500 was conducted on full-length thymosin beta-4, a different molecule
- Both are prohibited at all times under the WADA Prohibited List
- Neither is a controlled substance in the UK; neither is a licensed medicine
Quick reference
| Property | BPC-157 | TB-500 |
|---|---|---|
| Sequence | Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val | Ac-Leu-Lys-Lys-Thr-Glu-Thr-Gln |
| Length | 15 amino acids (pentadecapeptide) | 7 amino acids (heptapeptide) |
| CAS number | 137525-51-0 | 885340-08-9 |
| Molecular formula | C₆₂H₉₈N₁₆O₂₂ | C₃₈H₆₈N₁₀O₁₄ |
| Molar mass | ~1419.5 g/mol | ~889.0 g/mol |
| PubChem CID | 108101 | 62707662 |
| UNII | — | QHK6Z47GTG |
| Also known as | Body Protection Compound 157, PL 14736, bepecin | Thymosin beta-4 fragment 17–23 |
| Parent molecule | Gastric juice protein (partial sequence) | Thymosin beta-4, 43 amino acids, ~4921 g/mol |
| Classification | Research compound — not a licensed medicine | Research compound — not a licensed medicine |
What is BPC-157?
BPC-157 is a synthetic pentadecapeptide — fifteen amino acids — corresponding to a partial sequence of a protein identified in human gastric juice. The name stands for Body Protection Compound. It does not occur naturally in this isolated form; the fragment was synthesised from the larger parent sequence.
It has also appeared in the literature under the development code PL 14736 and the name bepecin. Research on it dates to Croatian work beginning in the 1990s, and it has been studied predominantly in laboratory animals.
What is TB-500?
TB-500 is a synthetic heptapeptide, Ac-LKKTETQ, corresponding to residues 17 to 23 of thymosin beta-4. The N-terminal acetylation slows enzymatic breakdown.
Thymosin beta-4 itself is a naturally occurring 43-amino-acid protein encoded by the TMSB4X gene, present in most mammalian cells at intracellular concentrations that can reach 0.5 mM. Its WHO international nonproprietary name is timbetasin. The LKKTET motif beginning at residue 17 is the actin-binding region, which is the part TB-500 reproduces.
TB-500 therefore retains one functional domain of the parent protein and none of the rest of it.
BPC-157 vs TB-500: the difference that matters
The two are frequently described as interchangeable healing peptides. Chemically and mechanistically they have almost nothing in common.
| BPC-157 | TB-500 | |
|---|---|---|
| Origin | Gastric juice protein fragment | Thymosin beta-4 fragment |
| Size | 15 residues | 7 residues |
| Proposed mechanism | Angiogenesis, nitric oxide pathway modulation, VEGF expression, growth factor signalling | Actin sequestration, cell migration |
| Naturally occurring | No — synthetic fragment | No — synthetic fragment of a natural protein |
Why BPC-157 and TB-500 are researched together
The reason is the non-overlap above. For a researcher designing a tissue-model study, two compounds acting through separate pathways give a broader read on the model than two acting through the same one.
It is worth being precise about what this justifies. Mechanistic complementarity is a reason to design an experiment. It is not evidence of a combined effect. No controlled human study has evaluated the two compounds together, and the popularity of the pairing runs well ahead of any direct research on it.
BPC-157 human trials: what the evidence actually contains
This is where most published material on BPC-157 becomes unreliable, so it is worth setting out plainly.
The preclinical literature is large. Animal and in vitro work spans angiogenesis, vascular signalling, fibroblast activity, inflammation, gastrointestinal injury and musculoskeletal tissue response.
The human literature is not. A 2025 narrative review of BPC-157 in musculoskeletal healing identified three published human studies: a retrospective study in knee pain, a small interstitial cystitis study, and a two-person intravenous pharmacokinetic and safety study. Fewer than thirty participants across all three. None was a randomised controlled trial. A 2025 systematic review in the American Journal of Sports Medicine screened 544 articles for orthopaedic applications and found one clinical study meeting inclusion criteria; the remaining thirty-five were animal models.
Two further points are rarely mentioned. A Phase I trial registered in 2015 (NCT02637284) would have been the first rigorous human safety study; it was never published. And the published human studies come from a single research group, so independent replication has not occurred.
Reviewers have converged on the same conclusion: the preclinical evidence is substantial, the human evidence is inadequate to support clinical recommendations, and properly designed trials are needed. Formal reviews also note unresolved questions around pharmacokinetics — no study has yet characterised the relationship between plasma concentration and observed biological effect, which is a prerequisite for any clinical development.
TB-500 and thymosin beta-4 are not the same compound
TB-500 has a subtler evidence problem than BPC-157, and almost nobody flags it.
Most of the human research cited in support of TB-500 was not conducted on TB-500. It used full-length recombinant thymosin beta-4 — a 43-amino-acid protein of roughly 4921 g/mol. TB-500 is a 7-amino-acid fragment of roughly 889 g/mol. Early-phase human work on the full protein has looked at ophthalmic and cardiac contexts, and those findings belong to the parent molecule.
The conflation runs deep enough that reference identifiers get mixed up too — TB-500 is sometimes published with thymosin beta-4’s PubChem CID rather than its own. Anyone reading supplier or community material on TB-500 should check which molecule a cited study or datasheet actually refers to.
Are BPC-157 and TB-500 legal in the UK?
Neither compound is listed as a controlled substance under the Misuse of Drugs Act 1971. Neither holds a UK marketing authorisation.
Under the Human Medicines Regulations 2012, a substance becomes a medicine when it is presented as treating, preventing or diagnosing a condition in people. Supplying either compound for human use, or marketing them with therapeutic, recovery or performance claims, makes them unlicensed medicinal products — a criminal offence. Lawful UK supply is as laboratory research reagents only, with research-use labelling, no medical claims and no dosing instructions.
This is a general summary and not legal advice. For anything specific, consult a qualified UK adviser and check the current legislation directly.
United States
Both compounds were placed on the FDA’s Category 2 bulk drug substances list in late 2023, excluding them from compounding pharmacy production for human use. The FDA framed this as reflecting insufficient safety and efficacy data rather than evidence of specific harm. An FDA advisory committee revisited BPC-157 in July 2026 and recommended adding it to the Section 503A Bulks List; as of publication the agency has not issued a final decision. This position may change and should be checked against current FDA guidance.
BPC-157 and TB-500 in sport
Both are prohibited at all times under the WADA Prohibited List, in and out of competition. Thymosin beta-4 and its derivatives were named explicitly in the 2018 list update.
Validated doping-control assays for the TB-500 fragment exist and athletes have been sanctioned for its use. TB-500 was encountered in racehorses before it was explicitly listed for human athletes and remains prohibited under racing medication rules. Published sources differ on the exact section reference, so anyone with a compliance interest should check the current WADA list directly rather than relying on secondary summaries.
Purity, certificates of analysis and verification
Because both compounds sit outside any medicines framework, the quality of the material rests entirely on analytical testing.
For research use, look for:
- An HPLC purity trace with the batch number visible on the document
- Mass spectrometry confirming the expected mass — approximately 1419.5 g/mol for BPC-157, approximately 889.0 g/mol for TB-500
- For TB-500 specifically, confirmation that the material is the acetylated 7-residue fragment and not full-length thymosin beta-4
- A batch-specific certificate rather than a generic specimen document
A CoA that cannot be traced to the vial in your hand is not verification. Our BPC-157, TB-500 and BPC157 + TB500 Blend are supplied with batch documentation, and current testing status is available via our COA archive.
Handling and storage
General handling practice reported in the literature for lyophilised research peptides:
- Store sealed vials at -20°C, protected from light and moisture
- Allow vials to reach room temperature before opening to avoid condensation
- Solution stability is lower than lyophilised stability; prepare working solutions close to point of use
- Check buffer compatibility before assay design
All handling, reconstitution and experimental procedures are determined by the receiving laboratory under its own protocols and risk assessments.
References
- Vasireddi N, et al. Systematic review of BPC-157 in orthopaedic sports medicine applications. American Journal of Sports Medicine. 2025.
- Regeneration or Risk? A Narrative Review of BPC-157 for Musculoskeletal Healing. PubMed PMID 40789979.
- Sikiric P, Seiwerth S, Rucman R, et al. Novel application of pentadecapeptide BPC 157 in gastrointestinal tract and beyond: a review of preclinical and clinical data. World Journal of Gastroenterology. 2020;26(29):4201-4228.
- Kang J, Hong G, Han S, et al. Pentadecapeptide BPC 157 and its effects on the gastrointestinal tract and its potential systemic implications. World Journal of Gastroenterology. 2023;29(45):7769-7781.
- BPC-157 as an Investigational Peptide Therapeutic: Biopharmaceutical Challenges, Formulation Strategies, and Translational Development Barriers. Pharmaceutics. 2026;18(5):625.
- Goldstein AL, Hannappel E, Kleinman HK. Thymosin β4: actin-sequestering protein moonlights to repair injured tissues. Trends in Molecular Medicine. 2005;11(9):421-429.
- World Anti-Doping Agency. Prohibited List. Current edition.
BPC-157 and TB-500 are supplied by Premium Lab Peptides strictly for in vitro laboratory research. Neither is a licensed medicine, neither is for human or veterinary consumption, and no guidance on human use is provided or implied. Premium Lab Peptides is a trading name of Invicta Alliance Limited.