- Enzalutamide will be given at the standard dose of 160 mg daily for 3 months. PSATRICOM (Prostvac-V/F) will consist of a single subcutaneous (sc) immunization of Prostvac-V in Week 1, followed by 6 Prostvac-F immunizations administered in Weeks 3, 5, 9, 13, 17, and 21. Patients will be retreated with a 3-month course of enzalutamide after PSA has returned to baseline values at study entry or higher. Patients will have had to be on study for at least 7 months or longer in order to be retreated with an additional course of enzalutamide therapy. Patients will be followed for PSA recovery after enzalutamide has been discontinued. Patients who do not develop a 25% decline in PSA after 3 months will not be evaluated for tumor re-growth and additional patients will be enrolled to evaluate for that endpoint. Patients will be stratified based on a doubling time of greater than or less than 6 months.