Accurate prediction of human pharmacokinetics from preclinical in vivo and in vitro data remains a critical goal in the drug discovery and development process to minimize risk during first-in-human studies.So far several methodologies are available to yield quantitative predictions of human pharmacokinetics and have been increasingly integrated into all stages of the drug research process.These predictive approaches typically use either in vivo preclinical data or results from drug metabolism and disposition using in vitro human tissue including microsomes or hepatocytes.The main parameters to describe the PK behavior include (volume of distribution at steady state (Vss), clearance (CL), and absorption constant, etc.Typical allometric scaling (SSS) and IVIVE approaches have great limitations.