Effect of erlotinib on CYP3A activity, evaluated in vitro and by dual probes in patients with cancer

In vitro, erlotinib (0–30 µmol/l) and 14C-labelled midazolam (MDZ) (5 µmol/l) were incubated with human liver microsomes; separately, microsomes were preincubated with erlotinib (10 µmol/l) before the addition of MDZ. Results showed a time-dependent inhibition of MDZ metabolism by erlotinib, with a