This is an open-label, 2-period crossover study in young healthy male subjects to evaluate the effect of multiple once daily doses of ketoconazole on the pharmacokinetics (PK) of darexaban and metabolites after a single dose of darexaban. In addition, safety and tolerability of darexaban administered alone and in combination with ketoconazole, is evaluated. Eligible subjects are admitted to the clinical unit in the morning of Day -1. The subjects are randomized to receive either first darexaban plus ketaconazole and then darexaban alone, or first darexaban alone followed by darexaban plus ketoconazole.
The primary objective of this study is to determine the effect of ketoconazole on the blood concentrations of darexaban and its metabolites (drug degradation products). The secondary objective of the study is to evaluate the safety and tolerability of a single dose of darexaban alone and when administered together with ketoconazole.