Xtandi Generic Name & Formulations
Enzalutamide 40mg; soft gelatin caps; or 40mg, 80mg; tabs.
Androgen receptor inhibitor.
Caps, tabs 40mg—120; Tabs 80mg—60
Castration-resistant prostate cancer (CRPC). Metastatic castration-sensitive prostate cancer (mCSPC).
Xtandi Dosage and Administration
Swallow whole. 160mg once daily. Give concurrent GnRH analog or patient should have had bilateral orchiectomy. Dose modifications: ≥Grade 3 toxicity or intolerable side effect: withhold dose for 1 week or until improvement to ≤Grade 2, then resume at same or reduced dose (120mg or 80mg), if warranted. Concomitant strong CYP2C8 inhibitors, if unavoidable: reduce to 80mg once daily. Concomitant strong CYP3A4 inducers, if unavoidable: increase to 240mg once daily. When CYP2C8 inhibitor or CYP3A4 inducer is discontinued, return enzalutamide dose to the dose used prior to initiation of the inhibitor or inducer.
Xtandi Boxed Warnings
Risk of seizure; permanently discontinue if occurs. Discontinue if posterior reversible encephalopathy syndrome (PRES) develops. Monitor for ischemic heart disease; discontinue if Grade 3 or 4 develops. Manage CV risk factors (eg, hypertension, diabetes, dyslipidemia). Evaluate for fall and fracture risk; monitor and manage as per established guidelines. Severe renal impairment or ESRD: not studied. Embryo-fetal toxicity. Advise males (w. female partners of reproductive potential) to use effective contraception during and for 3 months after the last dose.
Avoid concomitant strong CYP2C8 inhibitors (eg, gemfibrozil); if unavoidable, reduce dose (see Adult dose). Avoid concomitant strong CYP3A4 inducers (eg, rifampin); if unavoidable, increase dose (see Adult dose). Antagonizes midazolam (CYP3A4 substrate) and omeprazole (CYP2C19 substrate). May antagonize certain CYP3A4, CYP2C9, or CYP2C19 substrates; increase dose of these substrates, if unavoidable. Caution with concomitant drugs that may lower the seizure threshold.
Xtandi Adverse Reactions
Asthenia/fatigue, back pain, hot flush, constipation, arthralgia, decreased appetite, diarrhea, hypertension; seizure, PRES, ischemic heart disease, falls, fractures, hypersensitivity reactions (permanently discontinue if severe).
Xtandi Clinical Trials
Xtandi Patient Counseling