Metastatic Castrate-Resistant Prostate Cancer Subjects Treated With PROVENGE® + One Infusion of Sipuleucel-T

Inclusion Criteria: For a subject to be eligible for participation in this study, all of the following criteria must be satisfied: 1. Potential subjects are men aged ≥18 years who are clinically indicated for treatment with PROVENGE® (asymptomatic or minimally symptomatic metastatic castrate-resistant \[hormone refractory\] prostate cancer). 2. Have qualified for on-label PROVENGE® infusion 3. Have received all 3 infusions of PROVENGE® prior to randomization 4. Written informed consent provided prior to the initiation of study procedures 5. Estimated life expectancy ≥12 months Exclusion Criteria: A subject will not be eligible for participation in this study if any of the following criteria apply. 1. Men who are not clinically indicated for treatment with PROVENGE® (asymptomatic or minimally symptomatic metastatic castrate-resistant \[hormone refractory\] prostate cancer). 2. Need for systemic chronic immunosuppressive therapy, including antitumor necrosis factor alpha monoclonal antibodies, glucocorticoids, systemic steroids, blood products, GM-CSF or granulocyte colony-stimulating factor (G-CSF), any vaccinations, or experimental and investigational therapies (see Section 6.3.1) 3. Uncontrolled, concurrent illness, including, but not limited to the following: ongoing or active infection (bacterial, viral, or fungal), or psychiatric illness that would limit compliance with study requirements, as well as any condition that would preclude a subject from completing PROVENGE® or sipuleucel-T treatment. 4. On experimental or investigational therapy.