Utility of Intersystem Extrapolation Factors in Early Reaction Phenotyping and the Quantitative Extrapolation of Human Liver Microsomal Intrinsic Clearance Using Recombinant Cytochromes P450

  title={Utility of Intersystem Extrapolation Factors in Early Reaction Phenotyping and the Quantitative Extrapolation of Human Liver Microsomal Intrinsic Clearance Using Recombinant Cytochromes P450},
  author={Yuan Chen and Liling Liu and Khanh Nguyen and Adrian J. Fretland},
  journal={Drug Metabolism and Disposition},
  pages={373 - 382}
Reaction phenotyping using recombinant human cytochromes P450 (P450) has great utility in early discovery. However, to fully realize the advantages of using recombinant expressed P450s, the extrapolation of data from recombinant systems to human liver microsomes (HLM) is required. In this study, intersystem extrapolation factors (ISEFs) were established for CYP1A2, CYP2C8, CYP2C9, CYP2C19, CYP2D6, and CYP3A4 using 11 probe substrates, based on substrate depletion and/or metabolite formation… 

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