CYP3A Probes Can Quantitatively Predict the In Vivo Kinetics of Other CYP3A Substrates and Can Accurately Assess CYP3A Induction and Inhibition

One CYP3A probe (alfentanil) can predict the disposition of another CYP3A substrate (midazolam). Data are the ratios (treated/control) of area under plasma concentration–time curve extrapolated to infinity for oral and IV alfentanil and midazolam, in subjects treated with rifampin (hepatic and intestinal CYP3A induction), troleandomycin (hepatic and intestinal CYP3A inhibition), or grapefruit juice (intestinal CYP3A inhibition). Data are replotted from Kharasch et al. (10).