Development and evaluation of flurbiprofen plasters

Purpose: Topical delivery preparations of flurbiprofen have been used in the treatment of musculoskeletal pain. The purpose of this study was to develop a flurbiprofen plaster with improved stability and permeability in the absence of skin irritation. Methods: Commercially available pressure-sensitive adhesives (PSAs) were used to construct the drug layer of the plaster matrix. The resulting plasters from this study were compared with existing commercially available products. The drug permeation profile was assessed across human epidermis, and flurbiprofen and its impurities were analyzed. In addition, we evaluated skin irritation and measurement of adhesive properties. Results: Flurbiprofen plasters containing functional acrylic PSA and non-functional acrylic PSA were developed. The combination ratio of functional and non-functional types affected drug permeability and product stability. We confirmed that the plasters developed in this study exhibited relatively higher permeability through human cadaver skin compared to commercially available products. Additionally, these plasters demonstrated a minimal decrease in drug content and lower production of impurities. The skin irritation test showed non-irritating results, with a primary irritation index of 0.0. Conclusion: We successfully developed a flurbiprofen plaster and conducted a comprehensive comparison with existing products on the current market. Our newly developed plaster exhibited comparatively higher drug permeability over time, improved stability ensuring the maintenance of drug content, and reduced generation of impurities. Furthermore, it demonstrated satisfactory adhesion to the skin and non-irritating properties, making it a promising advancement in this field.