Prostate and other male cancers:
Indications for: ZYTIGA
In combination with prednisone for the treatment of metastatic castration-resistant prostate cancer (CRPC) and metastatic high-risk castration-sensitive prostate cancer (CSPC).
Adult Dosage:
Take on an empty stomach. Swallow whole with water. 1g once daily (in combination with oral prednisone 5mg twice daily [CRPC] or 5mg once daily [CSPC]). Also give concurrent GnRH analog or patient should have had bilateral orchiectomy. Baseline moderate hepatic impairment (Child-Pugh Class B): 250mg once daily; monitor closely; discontinue if ALT/AST >5xULN or total bilirubin >3xULN. If concomitant strong CYP3A4 inducer necessary, increase abiraterone dose frequency to twice daily during co-administration period (eg, from 1g once daily to 1g twice daily); reduce back to previous dose/frequency when CYP3A4 inducer is discontinued.
Children Dosage:
Not established.
ZYTIGA Warnings/Precautions:
Risk of mineralocorticoid excess; monitor BP, serum potassium, fluid retention at least monthly. Control hypertension and correct hypokalemia before and during treatment. Heart failure, recent MI, cardiovascular disease, ventricular arrhythmias; monitor closely. Monitor for adrenocortical insufficiency. Stress (may need higher corticosteroid dose). Monitor LFTs prior to starting treatment, every 2 weeks for the first 3 months, and monthly thereafter. Baseline moderate hepatic impairment (Child-Pugh Class B): monitor LFTs prior to initiation, weekly for the first month, every 2 weeks for the next 2 months, and monthly thereafter. Interrupt and reduce dose if hepatotoxicity (ALT/AST >5×ULN or total bilirubin >3×ULN) occurs; see full labeling. Permanently discontinue if concurrent ALT elevation >3×ULN and total bilirubin >2×ULN develops without biliary obstruction or other causes of elevation. Baseline severe hepatic impairment (Child-Pugh Class C): not recommended. Preexisting diabetes (esp. those taking thiazolidinediones-containing products). Embryo-fetal toxicity. Advise males with female partners of reproductive potential to use effective contraception during therapy and for 3 weeks after last dose. Pregnancy. Nursing mothers: not established.
ZYTIGA Classification:
CYP17 inhibitor.
ZYTIGA Interactions:
Increased risk of fracture and death when concomitant abiraterone plus prednisone/prednisolone with radium Ra 223 dichloride; not recommended. Antagonized by strong CYP3A4 inducers (eg, phenytoin, carbamazepine, rifampin, rifabutin, rifapentin, phenobarbital); avoid (or see Adult). Potentiates CYP2D6 (eg, dextromethorphan) or CYP2C8 substrates (eg, pioglitazone); monitor closely for toxicity. Avoid concomitant CYP2D6 substrates with narrow therapeutic index (eg, thioridazine); if no alternatives, consider dose reduction of substrate.
Adverse Reactions:
Fatigue, arthralgia, hypertension, nausea, edema, hypokalemia, hot flush, diarrhea, vomiting, upper respiratory infection, cough, headache, anemia, elevated LFTs, dyslipidemia, lymphopenia, hyperglycemia; hypoglycemia, hepatotoxicity (may be severe).
Note:
Pregnant women and those of childbearing potential should not handle Zytiga tablets without protection (eg, gloves). Partners must use appropriate barrier contraception.
Generic Drug Availability:
NO
How Supplied:
Tabs 250mg—120; 500mg—60
