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After more than a decade of clinical development for cancer and numerous failures, Phase III trials of cyclin-dependent kinase inhibitors are beginning.
An analysis of recent approved and failed marketing applications for new drugs evaluated by the European Medicines Agency highlights the factors that are most likely to be associated with non-approval.
Chris Lipinski, originator of the 'rule of five' guidelines for predicting the oral bioavailability of drug candidates, discusses their impact as well as efforts to expand drug-like chemical space and drug repositioning initiatives.