In addition to the safety of the parent drug, the safety of drug metabolites has to be demonstrated. The metabolites in safety testing (MIST) concept addresses the questions how to identify potential safety issues caused by drug metabolites and is the topic of our sixth e-book.

As the drug metabolites might have toxic effects, a concern arises if the metabolite is present only, or at disproportionately higher levels, in humans than in the animals used in the non-clinical toxicological studies. This e-book introduces the general principles of the safety metabolism work. In addition, why and when the work should be initiated and what should be taken into account when planning the studies are discussed. The tools to demonstrate the safety of drug metabolites or to identify potential safety issues, such as MIST analysis and radiolabeled metabolite in vivo Met Id and profiling, are covered by the e-book.