Serum PSA and PAP levels d. HLA-A2 typing Dosing is to occur, as follows: a. Day 1 for PROSTV AC-V or p lacebo (subcutaneous)* b. Days 1, 2, 3, and 4 for GM- CSF or placebo (subcutaneous) * Subjects should remain in the clinic for at least 30 minutes following administration of PROSTVAC -V or placebo for observation of adverse reactions. 7.3 Week 3 Through Week 21 (booster vaccinations) During the 21- week Treatment phase of this study, the study visits will occur on Weeks 3, 5, 9, 13, 17 and 21 (± 3 days for each individual visit). Medication assignment must be obtained through IVRS prior to dosing for each week of booster vaccinations. The following procedures will be performed and dosing will occur as follows : To be performed PRIOR to administration of study drug: 1. Adverse events (AEs) should be sought by non- directive questioning of the subject, self -reported, and/or directly observed at each clinic visit during the treatment phase of the study. 2. Concomitant medications will be reviewed and recorded at all visits. 3. Abbreviated physical exam (consisting of VS, temperature, and weight). Only significant changes in PE from Screening will be recorded 4. ECOG performance status 5. Blood samples , except for Week 3, will be obtained for: a. Hematology (CBC with differential, RBC wi th indices, platelet count) b. Serum Chemistry (BUN, creatinine, ALT, AST, alkaline phosphatase, total bilirubin, LDH, sodium, potassium, chloride, bicarbonate, calcium and glucose). c. Serum PSA and PAP levels (Weeks 5, 9, 13, 17, and 21) 6. Bone scan • Week 13 only 7. CT scan with contrast* (abdomen and pelvis): • Week 13, only if clinically indicated Protocol BNIT -PRV- 301; Amendment 7 PROSTVAC -V/F Version 2.7, 08 February 2017 CONFIDENTIAL AND RESTRICTED 48 Amend 7 Disclosure requires written consent from Bavarian Nordic , Inc. Dosing is to occur, as follows: a. Day 1 of each week: PROSTVAC -F or placebo** b. Days 1, 2, 3 and 4 of each week: GM- CSF or placebo * For subjects with allergies to contrast agents, MRIs for abdomen and pelvis may be performed. Only in cases where MRI is unavailable may a non- contrast CT be performed. For subjects enrolled in Germany, MRI must be used as the primary imaging modality. **Subjects should remain in the clinic for at least 30 minutes following administration of PROSTVAC -F or placebo for observation of adverse reactions. 7.4 End-of-Treatment Visit – Week 25 or When A Subject Discontinues Treatment The End- of-Treatment visit is approximately 4 weeks ± 3 days after the last injection of vaccine or placebo. T he tests and evaluations listed for the End- of-Treatment /Early Termination Visit should be carried out at the time of any premature subject withdrawal (subject - or investigator -directed) or whenever the investigator feels that the subject will be or is unable or unwilling to make any further visits. If a subject discontinues treatment early for any reason, every attempt should be made to document the reason for the discontinuation. Any subject who requests to stop study treatment or has been withdrawn from study treatment before completion of the protocol -specified treatment duration will be strongly encouraged to complete the evaluations below, and encouraged to participate in the Long- Term Follow -Up Phase of the s tudy provided the subject has not withdrawn full consent. 1. Adverse events – will be collected by non- directive questioning, self -reported or directly observed occurring since last visit, and discuss and/or resolve any previously reported or ongoing events. 2. Concomitant medications – record all medications being taken currently and record all previously taken, but discontinued drugs. 3. QoL (FACT -P, BPI -SF and EQ -5D-3L) where translations are available 4. Complete PE including VS, sitting BP, heart rate, RR, temperature, and weight 5. ECOG performance status 6. Blood samples will be obtained for: a. Hematology (CBC and differential, RBC with indices, platelet count) b. Serum chemistry (BUN, creatinine, ALT, AST, alkaline phosphatase, total bilirubin, LDH, sodium, potassium, chloride, bicarbonate, calcium and glucose) c. Coagulation panel (PT/(INR) / PTT) d. C-reactive protein Protocol BNIT -PRV- 301; Amendment 7 PROSTVAC -V/F Version 2.7, 08 February 2017 CONFIDENTIAL AND RESTRICTED 49 Amend 7 Disclosure requires written consent from Bavarian Nordic , Inc. e. Serum PSA and PAP f. Serum for immune and biomarker status g. Peripheral blood RNA/biomarker analysis h. CTC quantification (US sites only) i. Immune functional assays (US sites only) 7. Urinalysis 8. 12-lead E CG 9. Bone scan 10. CT scan with contrast * (abdomen and pelvis) * For subjects with allergies to contrast agents, MRIs for abdomen and pelvis may be performed. Only in cases where MRI is unavailable may a non- contrast CT be performed. For subjects enrolled in Germany, MRI must be used as the primary imaging modality. 7.5 Assessments During Long -Term Follow -Up The Long- Term Follow -Up (LTFU) phase begins immediately after the End- of-Treatment visit regardless of the total number of vaccinations actually received by a subject. The first visit is 6 calendar months ± 14 days after the End- of-Treatment visit with consecutive visits every 6 months ± 14 days thereafter. Subjects who progress prior to or during the LTFU phase will continue to be followed for survival and as described below until study closure or death. First LTFU visit at 6 Months ± 14 Days from the End -of-Treatment visit 1. Concomitant medications (limited to the treatment of prostate cancer therapy). All previously recorded medication entries should be reviewed for stop dates. 2. Prostate cancer treatment update for procedures, including interim unscheduled laboratory tests and/or radiological assessments. 3. Update for newly diagnosed autoimmune disease. 4. Physical exam (limited to assessment of subject’s prostate cancer status including prostate cancer progression), vital signs, and weight . 5. Qo L (FACT -P, BPI -SF and EQ -5D-3L) 6. Blood samples obtained for: i. Serum for immune and biomarker status. ii. Peripheral blood RNA/biomarker analysis iii. CTC quantification (US sites only) iv. PSA and PAP Protocol BNIT -PRV - 301; Amendment 7 PROSTVAC -V/F Version 2.7, 08 February 2017 CONFIDENTIAL AND RESTRICTED 50 Amend 7 Disclosure requires written consent from Bavarian Nordic , Inc. v.