Enzalutamide is a drug used to treat metastatic prostate cancer that no longer responds to hormonal therapy (castration-resistant prostate cancer). It blocks the hormone testosterone from binding to the androgen (male hormone) receptor. A very small percentage of patients who receive enzalutamide have had seizures. These men had no prior seizures, but had other medical conditions or factors that put them at risk for seizures.
In this study, researchers would like to see if there is a link between enzalutamide use and seizures in men with metastatic prostate cancer who are at risk for seizures due to a history of prior seizures, stroke, brain injury, or other factors. A patient will receive enzalutamide for four months. If there is no change in his medical condition and he is receiving benefit, he will continue receiving the treatment and see his doctor every 12 weeks for follow-up.