Preclinical safety testing of new drugs.

Preclinical safety testing is one important step in the development of new medicines. The requirements of such testing are the subject of government regulations and may vary in details, but not in general principles, in different countries around the world. The approach to preclinical safety testing of new drugs is multidisciplinary and requires the expertise of members from many different fields of science. The procedures described are guidelines rather than fixed protocols; they are subject to modifications according to the specific phamracological nature of the drug to be tested and also to the preference of the individual investigator. Under certain circumstances, special studies are necessary, such as electron microscopy, histochemistry, radioautography, and cytogenetics,--just to name a few. Routine studies for the safety assessment of new drugs include: (1) acute studies, (2) multiple-dose studies including carcinogenicity tests, (3) studies of fertility and general reproductive performance, (4) teratology studies, (5) perinatal and postnatal studies, (6) multiple-generation studies and (7) irritation studies.