Comprehensive assessment of ADMET risks in drug discovery.

The high attrition rate in drug development and the deteriorated drug ability as a result of the shifted chemical space of new therapeutic target for unmet medical needs have posed drastic challenges in current drug discovery. It has triggered the strategic transition in the past decade into parallel assessment of efficacy and comprehensive ADMET (absorption, distribution, metabolism, elimination and toxicity) properties of new chemical entities (NCEs) in the lead selection and optimization stages, to convert chemically a problematic NCE to an "all-around" candidate. This review summarizes multiple in silico, in vitro and in vivo ADMET filters developed and implemented in various stages of drug discovery to flag potential ADMET issues in the clinic. The full awareness of the benefits and limitations of each tool assures right questions to be answered using right tools at right time. The integrated ADMET risk assessment will allow project teams to have a clear vision in terms of the competitive position of own NCEs against comparable marketed drugs.