Patients are eligible if they have:

• Histologic diagnosis of adenocarcinoma of the prostate;
• At least 3 months but no more than 8 years prior to study entry, undergone a radical prostatectomy for stage T1b – T3c, N0-N1, M0 disease, with or without subsequent adjuvant or salvage radiation therapy.

Patients who experience their first PSA recurrence within 2 years post completion of initial therapy of curative intent are eligible without consideration of the Gleason score of the tumor specimen.* Patients who experience their first PSA relapse between 2 and 8 years post completion of initial therapy of curative intent are eligible only if the Gleason score of the tumor specimen was > 7; (* For patients who received adjuvant radiation, the date of the final dose of radiotherapy is used to mark the date of completion of therapy of curative intent. For patients who received salvage radiation for post-operative PSA recurrence but no adjuvant radiation, the date of surgery marks the date of completion of therapy of curative intent.)

• Therapeutic PSA response to primary therapy below 0.4 ng/mL;
• Tumor specimen positive for PAP, the vaccine’s target. Immunohistological staining of a specimen from the surgically excised tumor for expression of PAP is conducted by IMPATH, and may be completed even after LH-RH-analogue placement, as long as a positive (+) result is confirmed prior to randomization (Week 0). If a slide of the tumor cannot be obtained from the pathology archive, a chart record from a PRE-SURGERY blood sample showing serum PAP elevated above the upper limit of the local reference range may serve as a proxy.
• Experienced PSA relapse while not currently receiving androgen ablation therapy. Specifically, on record must be 2 PSA values separated by at least 3 months, both in the detectable range (>0.5 ng/mL), showing an increase of at least 0.3 ng/mL between the 2 measurements. The first of these 2 PSA values must rise above a previously recorded post-operative nadir value (which may be an undetectable PSA). In patients who received androgen ablation for a previous PSA relapse, PSA must have increased to a level at least 25% above the nadir observed while on this therapy and to an absolute level of at least 3 ng/mL;

• Prior hormone treatment for an earlier episode of PSA relapse is neither an exclusion nor an inclusion requirement for study entry. Patients who have previously been treated with adjuvant or salvage radiation following radical prostatectomy, or with either LH-RH-analogue (i.e., leuprolide or goserelin acetate) or non-steroidal anti-androgen therapy (i.e., bicalutamide 150 mg/day) for a prior PSA relapse, may enter the study provided:

  • post-prostatectomy PSA was never > 20 ng/mL;
  • PSA was not rising while receiving adequately dosed hormonal therapy;
  • for any hormonal therapy received, the last effective day of androgen deprivation was at least 6 months prior to study entry;
• Confirmed M0; a bone scan with no evidence of osseous metastasis must be on record, dated within 6 months prior to entry into the study;
• Estimated life-expectancy, inclusive consideration of co-morbidities, of at least 1 year;
• ECOG performance status of 0 or 1;
• Ability to understand the trial procedures and requirements;
• Age >18 and < 80 years;
• Ability to understand, and willingness to sign, informed consent.