What Is PT-141 (Bremelanotide)?
PT-141, also known as bremelanotide, is a cyclic heptapeptide melanocortin-receptor agonist derived from α-MSH. Unlike most research peptides, a bremelanotide drug product is FDA-approved for a specific indication — see the regulatory note below.
The short answer
PT-141 is a metabolite-derived analog in the melanocortin family, studied for its activity at central melanocortin receptors (notably MC4R). It is the research designation for the compound that, as a finished drug product (bremelanotide), has been approved for a specific medical indication. The research-grade material here is a distinct product for laboratory use.
Composition and specifications
| Compound | PT-141 (Bremelanotide) |
|---|---|
| Class | Cyclic melanocortin-receptor agonist (α-MSH-derived) |
| Also known as | Bremelanotide · CAS 189691-06-3 |
| Sequence / length | Cyclic heptapeptide |
| CAS number | 189691-06-3 |
| Molecular weight | 1025.2 g/mol |
| Purity (typical) | ≥98.0% |
| Appearance | White to off-white lyophilized powder; water-soluble |
Values above reflect the compound's published specification. As with any research material, the definitive confirmation of identity and purity for a given lot is the mass-spectrometry and HPLC data on its Certificate of Analysis.
How it is described mechanistically
PT-141 is characterized as an agonist at melanocortin receptors, with research emphasis on the central MC4R pathway. This central mechanism distinguishes it from peripheral-acting agents and is the basis for how it is studied in melanocortin-signaling research.
What has research examined?
PT-141 has both a clinical development history and a preclinical research literature. Areas examined include:
- Central melanocortin-receptor (MC4R) signaling
- Melanocortin-pathway pharmacology
- Comparisons with related α-MSH analogs
- Receptor-selectivity research
The existence of an approved bremelanotide drug product does not make research-grade material a medicine; the two are different products with different intended uses.
How is it characterized and tested?
Two questions matter most about any peptide sample in a research context: is it the right molecule, and how pure is it. Those are answered by analytical testing — commonly mass spectrometry for identity and HPLC for purity — with both reported on a batch-specific Certificate of Analysis (COA). An independent, published COA lets a researcher confirm identity and purity before beginning work. See peptide handling and storage for how samples are kept stable once received.
Primary literature: browse peer-reviewed studies on PT-141 at PubMed.
Common questions
Is PT-141 the same as bremelanotide?
Yes — PT-141 is the research designation for bremelanotide. As a finished drug product, bremelanotide is FDA-approved for a specific indication; the research-grade material offered here is not that approved product and is for laboratory research use only.
Is PT-141 approved for human use?
A bremelanotide drug product is FDA-approved for a defined medical indication. The research-grade material here is supplied for laboratory research use only and is not that approved product.
How does PT-141 relate to Melanotan II?
Both are melanocortin-receptor agonists derived from the α-MSH family. PT-141 is studied with emphasis on the central MC4R pathway.