Abstract
Objective: Although generic drugs are considered bioequivalent to the original drugs, for formulations such as adhesive agents, the sensation during use (hereinafter, “sensation”) and handling characteristics (hereinafter, “handling”) are usually not investigated during the approval process. Therefore, we established new drug evaluation criteria for transdermal adhesive agents, which included those relevant to handling and sensation, and investigated their usefulness.
Methods: This study assessed four test samples: the original loxoprofen sodium 100 mg tape (hereinafter, “LX-P 100 mg”) and three generic versions considered economically acceptable by our hospital. The formulations were evaluated based on our criteria for generic drugs. The handling and sensation were evaluated using a questionnaire with six parameters related to sensation and seven parameters related to handling. The enrolled subjects comprised 20 pharmacists from our hospital. Furthermore, a parallel evaluation using loxoprofen sodium 50 mg tape (hereinafter, “LX-P 50 mg”) was performed to explore the variance in the results of each individual criterion.
Results: The evaluation revealed differences between the formulations with regard to the thickness of the adhesive agent and stability after opening the package. Various differences were observed by evaluation of the handling and sensation. Based on the parameters used, the differences between the various formulations of LX-P 100 mg occurred in the following criteria: tactile sensation commensurate to the degree of adhesion; superficial resemblance to other agents; ease of adhesion; and ease of package opening. For LX-P 50 mg, the differences were found in superficial resemblance to other agents and ease of liner removal.
Conclusion: Our newly established criteria for the evaluation of LX-P 100 mg revealed differences between the samples, which were used to identify products with poor handling and sensation. Thus, this study successfully demonstrated the usefulness of the criteria for the purpose of medicine selection.
