This Phase II trial will enroll approximately 180 adult male patients with an earlier histologic diagnosis of prostatic adenocarcinoma and a biochemical recurrence (BCR) within 3 years of radical prostatectomy (RP) or definitive RT and no distant metastasis or locoregional recurrence. The trial is a randomized placebo-controlled double-blind study of a peptide cancer vaccine (RV001V).

Main Inclusion Criteria:

• Biochemical recurrence (BCR) within 3 years of radical prostatectomy (RP) or definitive RT and no distant metastasis by standard CT imaging and bone scintigraphy, or locoregional recurrence (including lymph nodes) assessed by CT or multi-parametric magnetic resonance imaging (MRI) and confirmed with negative biopsy in case of prior RT.
• In case of BCR after RP all the following criteria should apply: a. PSA ≥0.2 ng/mL, b. PSA Doubling Time (PSADT) >3 months and <12 months
• In case of BCR after RT all the following criteria should apply: a. PSA >nadir + 2 ng/mL, b. PSADT >3 months and <12 months
• ECOG performance status ≤2.
• Laboratory values obtained ≤30 days prior to first vaccination: Hemoglobin ≥5.6 mmol/L; Absolute granulocyte count ≥1.5 x 109 /L, Platelets ≥100 x 109 /L., Total bilirubin ≤1.5 x upper limit of normal (ULN).
• Creatinine ≤1.5 x ULN.
• Alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) ≤2.5 x ULN.

Main Exclusion Criteria:

• Patients who are receiving androgen-deprivation therapy or considered a candidate for immediate anti-androgen deprivation therapy (ADT) as judged by the investigator.
• Patients who have received prior ADT are not eligible with the exception of those that received ADT ≤36 months in duration and ≥9 months before randomization and administered only in the neoadjuvant/adjuvant setting.
• Patient is planned for salvage therapy with RT or radical prostatectomy.
• Castrate level of serum testosterone <50 ng/dL at screening.
• PSA >10 ng/mL