TB-500 and thymosin beta-4 at a glance
| Feature | TB-500 | Thymosin beta-4 |
|---|---|---|
| Identity | N-acetylated peptide fragment | Full-length beta-thymosin protein |
| Length | 7 amino acids | 43 amino acids |
| Sequence | Ac-LKKTETQ | Contains the related 17–23 region within a longer sequence |
| Evidence rule | Evaluate TB-500-specific studies | Do not transfer full-protein findings to TB-500 |
Sources for this section: FDA 2026 scientific review of TB-500-related substances · Analytical identification of the TB-500 fragment
Why the names are easy to conflate
TB-500 is related to a short region of thymosin beta-4, so articles and listings sometimes use the names together. The FDA has also noted that “TB-500” is a common name rather than a United States Adopted Name and that different salts or derivatives may be sold under the same label.
For shoppers, the practical rule is straightforward: identify the exact sequence and form on the product record and testing document. A shared nickname is not enough to establish identity.
Sources for this section: FDA discussion of TB-500 identity and naming
What TB-500-specific research shows
A 2024 study developed methods to measure TB-500 and its metabolites in laboratory systems and rats. In a fibroblast scratch assay, the investigators reported significant activity for one metabolite, Ac-LKKTE, rather than the parent TB-500 peptide.
That finding is useful for understanding metabolism and for questioning which molecule produced an observed laboratory effect. It does not establish a cosmetic benefit, topical delivery, or human outcome from a finished TB-500 serum.
Sources for this section: 2024 TB-500 metabolism and laboratory study (PubMed)
What thymosin beta-4 research cannot prove about TB-500
Full-length thymosin beta-4 has its own extensive biological research history, including work involving actin binding, cell migration, and repair models. Those publications study a different 43-amino-acid molecule.
They may explain why the related sequence attracts interest, but they cannot be used as direct evidence that the shorter TB-500 fragment produces the same behavior—much less that a particular topical formula produces a result in people.
Sources for this section: Review of thymosin beta-4 structure and research
What applies to VitaPep Serum+?
- VitaPep identifies the peptide as TB-500, the N-acetylated thymosin beta-4 17–23 fragment, Ac-LKKTETQ.
- The listed amount is 1.2 mg in a 30 mL bottle.
- The listed carrier is 70% DMSO and 30% deionized water.
- Pump and 1 mL dropper options are available; follow the current packaging for application amount.
- The formula is for external cosmetic use only and is not represented as a recovery, wound-care, or medical treatment.
Questions to ask before comparing TB-500 products
- Does the listing identify the seven-amino-acid sequence and chemical form?
- Does the testing document name the same sample and batch as the product?
- Is a claim based on TB-500 itself, one of its metabolites, or full-length thymosin beta-4?
- Does the research use the same topical route and finished formula?
- Are laboratory and animal findings clearly separated from human evidence?
Continue your research
FAQ
Frequently asked questions
Is TB-500 the same molecule as thymosin beta-4?
No. TB-500 is commonly identified as the N-acetylated seven-amino-acid fragment Ac-LKKTETQ. Thymosin beta-4 is a 43-amino-acid protein.
Can thymosin beta-4 studies prove what TB-500 does?
No. Full-length thymosin beta-4 and the shorter TB-500 fragment are related but distinct molecules. Findings should remain attached to the exact substance studied.
Is there established human evidence for topical TB-500 serum?
The sources reviewed here do not establish safety, delivery, or a defined outcome for a comparable finished topical TB-500 serum in people.
What does the TB-500 sequence Ac-LKKTETQ mean?
It describes an N-acetylated seven-amino-acid sequence related to residues 17 through 23 of thymosin beta-4. Sequence identity helps prevent research on different molecules from being combined.
Is VitaPep Serum+ TB-500 injectable?
No. It is presented only for topical external cosmetic use. Do not inject or ingest it.
Selected authoritative sources
These sources are provided so you can inspect the study type, molecule, route, and limitations directly. They do not endorse a VitaPep product.