Xtandi®Enzalutamide Soft Capsules

1. Indications and Usage
Metastatic Castration-Resistant Prostate Cancer (mCRPC): Treatment of adults with mCRPC who have progressed after androgen deprivation therapy (ADT) .
Non-Metastatic Castration-Resistant Prostate Cancer (nmCRPC): Treatment of adults with nmCRPC at high risk of metastasis .
Metastatic Castration-Sensitive Prostate Cancer (mCSPC): Treatment of adults with metastatic castration-sensitive prostate cancer .
2. Dosage and Administration
Administration: Oral administration. Swallow capsules whole with water. Do not chew, dissolve, or open the capsules .
Food Requirement: Can be taken with or without food .
Standard Dose:
Recommended Dose: 160 mg once daily (typically 4 capsules of 40 mg each) .
Missed Dose: If a dose is missed, take it as soon as possible on the same day. If a whole day is missed, resume at the usual time the next day. Do not take a double dose .
Dose Reduction: For severe toxicities, interrupt treatment until symptoms resolve (≤Grade 2), then resume at a reduced dose (e.g., 120 mg or 80 mg) .
3. Mechanism of Action
Enzalutamide is an androgen receptor (AR) inhibitor.
It works by competitively inhibiting the binding of androgens to the AR, preventing nuclear translocation of the receptor, and inhibiting the binding of the receptor to DNA.
This multi-step blockade reduces prostate cancer cell proliferation and induces apoptosis .
4. Safety and Warnings
Seizures: Enzalutamide may cause seizures. Use with caution in patients with a history of seizure or conditions that predispose to seizures. Discontinue if a seizure occurs .
Hypertension: Monitor blood pressure regularly during treatment .
Fall and Fracture Risk: Assess risk for falls and fractures .
Embryo-Fetal Toxicity: May cause fetal harm. Males with female partners of reproductive potential must use effective contraception during treatment and for 3 months after the final dose .
5. Adverse Reactions
Common adverse reactions (incidence ≥10%) include:
General: Fatigue/Fatigue, Pyrexia, Weight loss .
Cardiovascular: Hypertension, Hot flashes .
Musculoskeletal: Arthralgia, Back pain .
Gastrointestinal: Decreased appetite, Diarrhea, Constipation .
Neurologic: Dizziness, Headache .
6. Drug Interactions
CYP2C8 Inhibitors: Avoid concomitant use with strong CYP2C8 inhibitors (e.g., gemfibrozil). If necessary, reduce Enzalutamide dose to 80 mg once daily .
CYP Inducers/Inhibitors: Enzalutamide is a CYP inducer and may decrease the exposure of other drugs (e.g., warfarin, oral contraceptives). Monitor INR if taking warfarin .
7. Pharmaceutical Information
Chemical Name: N-[(3R)-1,3-Dimethyl-2,6-dioxo-1,2,3,6-tetrahydro-7H-purin-7-yl]-N’-[(1r,4r)-4-(4,4,5,5,5-pentafluoropentylsulfinyl)cyclohexyl]sulfamide (Note: Chemical name structure may vary by specific salt/formulation) [Reference based on general knowledge for Enzalutamide].
Molecular Formula: C21H22N4O4S [Standard Enzalutamide Formula].
Storage: Store at 20°C to 25°C (68°F to 77°F); excursions permitted to 15°C to 30°C (59°F to 86°F) [Reference].