ABSTRACT
This chapter provides a status on the background and a review of the pre-International Conference on Harmonization requirements (ICH) and the requirements or recommendations provided in the different guidelines issued by the ICH working groups. The stress testing program is described as a necessary preliminary step to anticipate the nature of the impurity profile and to justify the choice of the analytical methods and the degradation product levels specified in the final dossier. The data should be presented in a clear, rapidly understandable format. The results and conclusions of the stress testing program will be used often during the review of other parts of the dossier. The ICH principles of stress testing are clear, one batch of drug substance is sufficient, providing that the manufacturing process, the physicochemical properties and the quality of this batch are representative of those of the batch described in the marketing application.
