General pharmacology, the international regulatory environment, and harmonization of guidelines

The performance of general pharmacology procedures on new drug candidates supports both drug discovery and safety assessment activities; however, the potential contribution of general pharmacology to safety assessment has had less attention than other aspects of non‐clinical testing. Pharmaceutical companies are divided as to whether or not general pharmacology is integrated with the rest of toxicology testing or carried out as part of the discovery program, and, recently, discussions have taken place within Europe as to whether or not these studies should be subject to Good Laboratory Practice (GLP) conditions. All three regions (the United States, Europe, and Japan) require data on the pharmacological properties of new drugs to be included in a marketing application. This should cover primary and secondary pharmacological effects, and should provide information concerning potential adverse reactions. In addition, Europe and the United States request non‐clinical data on potential drug interactions. However, the most detailed requirements are described in the Japanese guidelines. This paper reviews the current regulatory environment in the European Community (EC), Japan, and the United States, highlighting some general features of the three regulatory systems which are relevant to general pharmacology, and summarising the specific guidelines for these studies in the three regions. Although there are significant differences between the detailed Japanese general pharmacology requirements and the more flexible Western approach, it is not clear that it is appropriate to include general pharmacology within the international harmonization discussions. Rather, deregulation in this area is a desirable goal for the future.