- Maintaining castrate status: patients who had not undergone surgical orchiectomy must have continued on medical therapies, such as gonadotropin-releasing hormone analogs, to maintain castrate levels of serum testosterone. Those receiving an antiandrogen as part of their first-line hormonal therapy must have shown progression of disease off of the antiandrogen prior to enrollment (6 weeks withdrawal for bicalutamide; 4 weeks for flutamide)