ABSENCE OF HEPATIC ENZYME INDUCTION IN PROSTATE CANCER PATIENTS RECEIVING 'CASODEX' (BICALUTAMIDE)

The potential for hepatic enzyme induction by bicalutamide (`Casodex‘) was assessed in an open study in prostate cancer patients. A single, oral dose of antipyrine 1000 mg was given before and after 12 weeks' bicalutamide therapy [once daily 50 mg (n=7) or 150 mg (n=11)] and its pharmacokinetics and metabolism were determined. Plasma or saliva samples were taken for the measurement of antipyrine concentration. Urine samples were assayed for antipyrine and Its three major metabolites. With bicalutamide 50 mg, plasma antipyrine concentrations were maximal between 2 and 4 h after administration, declined in a log-linear manner and were unaffected by bicalutamide therapy; with bicalutamide 150 mg, saliva antipyrine concentrations were maximal between 2 and 4 h, declined in a log-linear manner, and were also unaffected by bicalutamide therapy. Antipyrine half-life was 16.3% shorter after bicalutamide 50 mg (p