科学的かつ客観的な視点からの医薬品情報収集・吟味の重要性に関する調査研究

To select a drug suitable for a patient from drugs with the same indication, scientific and objective comparative evaluation of drug information is important. However, some of the secondary sources comparing drugs with the same indication lack scientific accuracy. For example, among proton pump inhibitors（PPIs）approved in Japan, benzimidazole derivatives, such as omeprazole, esomeprazole, lansoprazole, and rabeprazole, possess similar chemical structures and inhibit the gastric mucosal parietal cell proton pumps by similar irreversible mechanisms. However, contrary to this scientific fact, there are secondary sources stating that only rabeprazole is reversible. Hence, this study aimed to demonstrate the importance of gathering and examining drug information from a scientific and objective perspective by clarifying the background to the interpretation that only rabeprazole is reversible in secondary sources. We conducted a comprehensive survey of the descriptions of the inhibitory mechanism of rabeprazole in the package inserts and the interview forms of the brand-name drug, Pariet^®, along with all the 23 generic versions of rabeprazole. Additionally, we also investigated the reference papers of each description. Furthermore, we compared the descriptions in the package inserts and the interview forms of the four brand-name PPIs. It was observed that several documents described rabeprazole as the only reversible PPI. Moreover, only Pariet^®（rabeprazole）was described as"glutathione may restore enzyme activity"in the interview form among the four brand-name PPIs. However, it is clear from their chemical structures that all the benzimidazole-derivative PPIs, including rabeprazole, have the same mechanism of action. Thus, the widespread notion that only rabeprazole is reversible is possibly because"recovery of enzyme activity"is indicated only for rabeprazole among the four brand-name PPIs. Thus, there is a risk that drug information may be misinterpreted depending on how it is read. Overall, it is important to objectively and scientifically examine the description of drug information when determining the appropriate drug for a patient.