Casodex (bicalutamide) 150-mg monotherapy compared with castration in patients with previously untreated nonmetastatic prostate cancer: results from two multicenter randomized trials at a median follow-up of 4 years.

Objectives: To compare the efficacy, tolerability, and quality of life benefits of bicalutamide (Casodex) 150-mg/day monotherapy and castration in previously untreated nonmetastatic (M0) advanced prostate cancer.

Methods: A total of 480 patients with Stage T3/T4 nonmetastatic disease randomly received oral bicalutamide 150 mg/day or castration (either bilateral orchiectomy or goserelin acetate [Zoladex] 3.6 mg every 28 days) in a 2:1 ratio in two open multicenter studies (studies 306 and 307). The design of these studies was similar to allow a pooled analysis.

Results: In the combined survival analysis, at median follow-up of 202 and 205 weeks in studies 306 and 307, respectively, with 31% of the cases resulting in death, bicalutamide 150-mg monotherapy was statistically equivalent to castration; the risk of death from any cause was 7% less with bicalutamide than with castration (hazard ratio [HR] = 0.93). Data on time to treatment failure and objective progression could not be pooled, as results for these end points differed between the trials. In study 306, bicalutamide 150-mg monotherapy increased time to objective progression (HR = 0.58; P = 0.033) and treatment failure (HR = 0.66; P = 0.074), whereas in study 307, time to progression (HR = 1.35; P = 0.0471) and treatment failure (HR = 1.24; P = 0.097) favored castration. Bicalutamide therapy showed significant advantages over castration for both sexual interest (P = 0.029) and physical capacity (P = 0.046). Bicalutamide 150-mg monotherapy was well tolerated.

Conclusions: Bicalutamide 150-mg monotherapy provides a similar survival outcome to castration in previously untreated patients with nonmetastatic advanced prostate cancer and confers statistically significant benefits over castration with respect to sexual interest and physical capacity.