Indications: Prostate cancer: Treatment of metastatic, castration-resistant prostate cancer (in combination with prednisone).

Cautions: monitor blood pressure, serum potassium concentration, and fluid balance before treatment, and at least monthly during treatment— for management of hypertension, hypokalaemia and oedema; history of cardiovascular disease—correct hypertension and hypokalaemia before treatment (if significant risk of congestive heart failure, such as history of cardiac failure, uncontrolled hypertension or cardiac events, for management and increased monitoring); diabetes (increased risk of hyperglycaemia—monitor blood sugar frequently); concurrent chemotherapy—safety and efficacy not established; increased risk of myopathy and rhabdomyolysis with possible renal failure (caution with concomitant use of drugs known to be associated with myopathy or rhabdomyolysis) monitor liver function before treatment, then every 2 weeks for the first 3 months of treatment, then monthly thereafter—interrupt treatment if serum alanine aminotransferase or aspartate aminotransferase greater than 5 times the upper limit ( for details of restarting treatment at a lower dose) and discontinue permanently if 20 times the upper limit.

Contra-indications: Women who are or may become pregnant

Canadian labeling: Additional contraindication (not in U.S. labeling): Hypersensitivity to abiraterone acetate or any component of the formulation or container.

Renal impairment: No dosage adjustment necessary. Hepatic Impairment hepatic impairment prior to treatment initiation:

Mild (Child-Pugh class A): No dosage adjustment necessary. Moderate (Child-Pugh class B): 250 mg once daily. Permanently discontinue if ALT and/or AST >5 times the upper limit of normal (ULN) or total bilirubin >3 times ULN during treatment.Severe (Child-Pugh class C):

Avoid use Hepatotoxicity during treatment: ALT and/or AST >5 times ULN or total bilirubin >3 times ULN: Withhold treatment until liver function tests return to baseline or ALT and AST ≤2.5 times ULN and total bilirubin ≤1.5 times ULN, then reinitiate at 750 mg once daily.

Recurrent hepatotoxicity on 750 mg/day: Withhold treatment until liver function tests return to baseline or ALT and AST ≤2.5 times ULN and total bilirubin ≤1.5 times ULN, then reinitiate at 500 mg once daily.

Recurrent hepatotoxicity on 500 mg once daily: Discontinue treatment.

Side Effects: Note: Adverse reactions reported for use in combination with prednisone. MOST COMMON: Cardiovascular: Edema, hypertension. Central nervous system: Fatigue, insomnia. Dermatologic: Bruise.

Endocrine & metabolic: Hypertriglyceridemia, hyperglycemia, hypernatremia, hypokalemia, hypophosphatemia, hot flash. Gastrointestinal: Constipation, diarrhea, dyspepsia. Genitourinary: Urinary tract infection. Hematologic & oncologic: Lymphocytopenia. Hepatic: Increased serum ALT, increased serum AST. Neuromuscular & skeletal: Joint swelling (including joint discomfort), myalgia.

Respiratory: Cough, upper respiratory infection, dyspnea, nasopharyngitis.

MOST COMMON: Cardiovascular: Cardiac arrhythmia, chest pain (including chest discomfort), cardiac failure. Central nervous system: Falling. Dermatologic: Skin rash. Genitourinary: Hematuria, groin pain, polyuria, nocturia. Hepatic: Increased serum bilirubin. Neuromuscular & skeletal: Bone fracture. Miscellaneous: Fever.

RARE: (Limited to important or Life threatening): Adrenocortical insufficiency, hypersensitivity pneumonitis, noninfectious.

Dose: Prostate cancer, metastatic, castration-resistant: Oral: 1000 mg once daily (in combination with prednisone) Dosage adjustment for concomitant strong CYP3A4 inducers: Avoid concomitant strong CYP3A4 inducers; if a strong CYP3A4 inducer must be administered concurrently, increase the abiraterone frequency to twice daily (eg, from 1000 mg once daily to 1000 mg twice daily). Upon discontinuation of the strong CYP3A4 inducer, reduce abiraterone back to the prior dose and frequency.