[Changes in Test Methods for Internationalization in the Japanese Pharmacopoeia (Part 2): Establishment of a Quantitative Method for Lorazepam Using HPLC Analysis].

The Japanese Pharmacopoeia (JP) is an official normative publication that is referred to, for establishing the authenticity and properties and maintaining the quality of pharmaceutics in Japan. Partial amendments are periodically made to these guidelines to keep up with the progress of science and technology, and the international harmonization is revised every 5 years. Thus, "Internationalization of the JP" is one of the more important issues to address for the revision of the JP. For example, the incorporation of the test methods that have been used in other pharmacopeias, such as the United States Pharmacopeia (USP) and the European Pharmacopoeia (EP), into the JP is a useful approach. In light of this, we have recently reported changes in test methods in the 17th JP, "Establishment of a quantitative test method for clonidine hydrochloride from using a potentiometric titration method to using HPLC". As a part of our ongoing research to change test methods for internationalization, we selected lorazepam. Lorazepam is analyzed using a potentiometric titration method as listed in the 17th JP; however, both the USP and EP use HPLC for quantitative analysis of this drug. In this study, we synthesized the related impurities of lorazepam listed in the USP and the EP and determined their purities using quantitative NMR. The separation conditions of these compounds, including lorazepam, were examined using HPLC and simultaneous analyses were performed. In addition, lorazepam extracted from the tablets was analyzed using conditions similar to those used for the analysis of the related impurities.

[Changes in Test Methods for Internationalization in the Japanese Pharmacopoeia (Part 1): Establishment of a Quantitative Test Method for Clonidine Hydrochloride Using HPLC Analysis].

The Japanese Pharmacopoeia (JP) is an official normative guide for maintaining the authenticity of properties and qualities of medicine in Japan. The JP is revised every 5 years, and partial amendments are made from time to time to keep abreast with progress in science and technology and international harmonization. We are conducting a related study on the elimination of toxic reagents from the JP. The elimination of toxic reagents is an important study in relation to the five pillars of the revision of the 18th JP, "Improvement in quality by proactively introducing the latest knowledge and technological advances". In addition, "Internationalization of the JP" is an important issue to be addressed during revision of the JP. Considering international harmonization of the JP, it is important to incorporate the test methods that have been used in other pharmacopoeia, such as the United States Pharmacopeia (USP) and the European Pharmacopoeia (EP) in the JP. To achieve the above, herein, we selected clonidine hydrochloride, which is listed in the 17th JP. A potentiometric titration method is used as a quantitative method for clonidine hydrochloride in the 17th JP; in contrast, a HPLC method is utilized in the USP and the EP. In this study, we synthesized impurities of clonidine hydrochloride and determined their purities using quantitative NMR. In addition, the complete separation conditions of these compounds by HPLC were examined, and simultaneous analysis was performed.