Randomized phase II/III study of Risedronate in combination with Docetaxel versus Docetaxel alone in patients with hormone refractory prostate cancer

INTERVENTION: Arm A: Docetaxel 75 mg/m2 every 3 weeks. Every patient will receive prednisone 5 mg bid. Arm B: Docetaxel 75 mg/m2 every 3 weeks plus 30 mg Risedronate once daily. Every patient will receive prednisone 5 mg bid. Treatment will be given until progression, or 10 courses. After progression Risedronate 30 mg od + prednisone 5 mg will be continued. CONDITION: Prostate Cancer ; Cancer ; Malignant neoplasm of prostate PRIMARY OUTCOME: 1. Assess the objective PSA response to treatment by serial measurements of serum PSA as defined by the 'Bubley'.; 2. Compare time to progression between concomitant and sequential use of docetaxel and risedronate, in combination with prednisone. SECONDARY OUTCOME: Compare the following parameters: ; 1. PSA response (Nubley rate); 2. PPI according to McGIll‐Melzack toxicity profile; 3. Objective response (RECIST); 4. Duration of PSA response; 5. Survival INCLUSION CRITERIA: 1. Histologically proven prostate adenocarcinoma 2. Hormone refractory 3. Continued elevated PSA for at least 6 weeks after discontinuation of anti‐androgens prior to registration; last PSA level >5 ng/ml 4. Stable analgesic regimen for at least one week prior to registration 5. Patients without surgical castration must continue on LHRH antagonists 6. Adequate bone marrow, liver, renal function 7. WHO 0‐2