Drug Interaction Report

GENERALLY AVOID: Coadministration with inducers of CYP450 2C8 and/or 3A4 may decrease the plasma concentrations of enzalutamide, which is primarily metabolized by CYP450 2C8 to its pharmacologically active metabolite, N-desmethyl enzalutamide, and to a lesser extent by CYP450 3A4. However, the interaction has not been evaluated in vivo.

MANAGEMENT: Concomitant use of enzalutamide with potent CYP450 2C8 and/or 3A4 inducers such as carbamazepine, lumacaftor, mitotane, phenobarbital, phenytoin, primidone (partially metabolized to phenobarbital), rifamycins, and St. John's wort should generally be avoided. Moderate inducers such as bosentan, efavirenz, etravirine, modafinil, nafcillin, and nevirapine should also be avoided if possible. The extent to which other, less potent CYP450 3A4 inducers may interact with enzalutamide is unknown. Caution is advised if they are used with enzalutamide.

The recommended maximum number of medicines in the 'antineoplastic hormones' category to be taken concurrently is usually one. Your list includes two medicines belonging to the 'antineoplastic hormones' category:

• apalutamide
• Xtandi (enzalutamide)

Note: In certain circumstances, the benefits of taking this combination of drugs may outweigh any risks. Always consult your healthcare provider before making changes to your medications or dosage.