An Open Label Phase II Study of First-Line Maintenance Enzalutamide Following Docetaxel Plus Androgen-Deprivation Therapy in Patients With Previously-Untreated, Metastatic, Castration-Naive Prostatic Adenocarcinoma

Inclusion Criteria: For inclusion of a subject in the study, all of the following inclusion criteria must be fulfilled: Subject is a male at least 20 years of age. Subject has a histologically or cytologically confirmed diagnosis of adenocarcinoma of prostate. Subject has radiologic and clinical evidence of metastatic disease initially or after treatment for localized disease. They must have metastatic or progressive disease for which there is no further curative treatment available. Subject has an ECOG performance status of 0 to 1. Subject has a life expectancy of 3 months or more. At least 4 weeks since the last surgical procedures or radiotherapy prior to enrolment. Subjects must have recovered to <Grade 2 from all acute toxicities or toxicity must be deemed irreversible by the investigator. Acceptable liver function: Acceptable renal function Acceptable hematologic status (without growth factor support or transfusion dependency): Subject must agree to use an adequate method of contraception (condom) if he is having sex with a woman of childbearing potential or with a woman who is pregnant. Written and voluntary informed consent understood, signed and dated. Exclusion Criteria: For inclusion of a subject in the study, any of the following inclusion criteria must not be fulfilled: Ongoing treatment with an anticancer agent not contemplated in this protocol Pathologic finding consistent with neuroendocrine or small cell carcinoma Any history of clinically relevant coronary artery disease or myocardial infarction within the last 3 years, New York Heart Association (NYHA) grade III or greater congestive heart failure, cerebrovascular attack within the prior year, or current serious cardiac arrhythmia requiring medication except atrial fibrillation. Known uncontrolled brain, leptomeningeal or epidural metastases (unless treated and well controlled for at least 4 weeks prior to Cycle 1 Day 1). Subjects that develop brain metastasis during the study may have their treatment interrupted to receive a course of cranial radiation and restart trial medication after a recovery period of at least 1 week. High dose corticosteroids may be employed for the management of cranial radiation but must be tapered off before resuming treatment. Non-tolerable >Grade 2 neuropathy or evidence of unstable neurological symptoms within 4 weeks of Cycle 1 Day 1. Major surgery, other than diagnostic surgery, within 4 weeks prior to Cycle 1 Day 1, without complete recovery. Active, uncontrolled bacterial, viral, or fungal infections, requiring systemic therapy. Subjects who have exhibited allergic reactions to taxanes. Concomitant disease or condition that could interfere with the conduct of the study, or that would, in the opinion of the Investigator, pose an unacceptable risk to the subject in this study. The subject has legal incapacity or limited legal capacity. Dementia or significantly altered mental status that would limit the understanding or rendering of informed consent and compliance with the requirements of this protocol. Unwillingness or inability to comply with the study protocol for any reason.