ABSTRACT
This chapter provides guidance for registration applications on the content and qualification of impurities in new drug products produced from chemically synthesized new drug substances not previously registered in a region or member state. This guideline is complementary to the ICH Q3A(R) guideline Impurities in New Drug Substances, which should be consulted for basic principles. The ICH Q3C guideline Residual Solvents should also be consulted, if appropriate. This guideline addresses only those impurities in new drug products classified as degradation products of the drug substance or reaction products of the drug substance with an excipient and/or immediate container closure system. Safety studies should provide a comparison of results of safety testing of the new drug product or drug substance containing a representative level of the degradation product with previously qualified material, although studies using the isolated degradation products can also be considered.
