Drug Interactions between apalutamide and brivaracetam

ADJUST DOSE: Coadministration with potent inducers of CYP450 2C19 may decrease the plasma concentrations of brivaracetam. According to the prescribing information, brivaracetam undergoes hydroxylation mediated primarily by CYP450 2C19, although it appears to be a relatively minor, secondary biotransformation pathway. When a single 150 mg dose of brivaracetam was administered to 26 healthy volunteers following five days of treatment with 600 mg/day of rifampin, a potent CYP450 2C19 inducer, brivaracetam systemic exposure (AUC) and half-life decreased by 45% compared to administration alone. Data are not available for other potent CYP450 2C19 inducers such as apalutamide, but a similar interaction with brivaracetam may be expected.

MANAGEMENT: Dosage adjustments for brivaracetam should be considered when coadministered with potent CYP450 2C19 inducers and following their discontinuation. The manufacturer recommends increasing the brivaracetam dosage by up to 100% (i.e., doubling the dosage) when prescribed with rifampin. Clinical response and tolerability should be monitored closely.