Simultaneous in vivo phenotyping of CYP enzymes

Abstract

As major determinants of the duration of drug action the CYP enzymes strongly in fluence drug ef ficacy and toxicity. In vivo phenotyping for CYP activities using cocktails of well-tolerated CYP-speci fic substrates may be valuable in the development of personalized medicine protocols, particularly for drugs that have signi ficant toxicity pro files. However, the use of the cocktail approach in the clinic is dependent on the rapid provision of patient-speci fic information to the clinician. Here we describe the application of liquid chromatography-tandem mass spectrometry (LC-MS-MS) for the simultaneous phenotyping of five major drug-metabolizing CYPs in patients within a 5-min assay. © Springer Science+Business Media New York 2013.