Posology: The recommended dose is 160 mg enzalutamide (four 40 mg capsules) as a single oral daily dose.
Medical castration with an LHRH analogue should be continued during treatment of patients not surgically castrated.
If a patient misses taking Xtandi at the usual time, the prescribed dose should be taken as close as possible to the usual time. If a patient misses a dose for a whole day, treatment should be resumed the following day with the usual daily dose.
If a patient experiences a ≥ Grade 3 toxicity or an intolerable adverse reaction, dosing should be withheld for one week or until symptoms improve to ≤ Grade 2, then resumed at the same or a reduced dose (120 mg or 80 mg) if warranted.
Concomitant use with strong CYP2C8 inhibitors: The concomitant use of strong CYP2C8 inhibitors should be avoided if possible. If patients must be co-administered a strong CYP2C8 inhibitor, the dose of enzalutamide should be reduced to 80 mg once daily. If co-administration of the strong CYP2C8 inhibitor is discontinued, the enzalutamide dose should be returned to the dose used prior to initiation of the strong CYP2C8 inhibitor (see Interactions).
Older people: No dose adjustment is necessary for older people (see Pharmacology: Pharmacodynamics and Pharmacokinetics under Actions).
Hepatic impairment: No dose adjustment is necessary for patients with mild, moderate or severe hepatic impairment (Child-Pugh Class A, B or C, respectively). An increased drug half-life has however been observed in patients with severe hepatic impairment (see Precautions and Pharmacology: Pharmacokinetics under Actions).
Renal impairment: No dose adjustment is necessary for patients with mild or moderate renal impairment (see Pharmacology: Pharmacokinetics under Actions). Caution is advised in patients with severe renal impairment or end-stage renal disease (see Precautions).
Paediatric population: There is no relevant use of enzalutamide in the paediatric population in the indication of treatment of patients with castration-resistant prostate cancer.
Method of administration: Xtandi is for oral use. The capsules should be swallowed whole with water, and can be taken with or without food.