To compare overall survival after receiving mitoxantrone and prednisone or docetaxel and prednisone in subjects with hormone-refractory metastatic prostate cancer.

Inclusion Criteria:

• Histologically or cytologically proven prostate adenocarcinoma

• Androgen independent prostate Cancer S/P orchiectomy and/or LHRH agonist Testosterone < 50 ng/dl (ie 1.735 nmol/l)

• Documented progressive disease

• Patients should have achieved stable analgesia for 7 days

• Karnofsky Performance Status ≥ 70

• No prior treatment with cytotoxic agent (except estramustine)

• Normal cardiac function must be confirmed by Left ventricular ejection fraction

• Adequate organ function:

  1. Hematology:

     • Neutrophils > 1.5 x 10^9/L
     • Hemoglobin > 10 g/dl. Erythropoietin use is allowed, but red blood cell transfusion to upgrade the hemoglobin level is not allowed
     • Platelets > 100 x 10^9/L

  2. Hepatic function:

     • Total bilirubin < the upper-normal limit of the institution.
     • Alanine aminotransferase and Aspartate transaminase < 1.5 times the upper-normal limit of the institution.

  3. Renal function:

     • Creatinine < 1.5 times the upper normal limit (ie National Cancer Institution grade < 1)

• No brain or leptomeningeal metastases

Exclusion Criteria:

• Prior radiotherapy to >25% of bone marrow (whole pelvic irradiation is not allowed)

• prior cytotoxic chemotherapy, except monotherapy with estramustine

• prior isotope therapy

• history of another cancer within the preceding five year

• symptomatic peripheral neuropathy grade ≥ 2

• other serious illness or medical condition:

  1. Congestive heart failure even if controlled. Previous history of myocardial infarction or angina pectoris within 1 year from study entry, uncontrolled hypertension or uncontrolled arrhythmias.
  2. Active uncontrolled infection
  3. Peptic ulcer, unstable diabetes mellitus or other contraindications for the use of corticosteroids.
  4. Auto-immune disease (lupus, sclerodermia, rheumatoid polyarthritis)

• treatment with any other anti-cancer therapy

• treatment with bisphosphonates

The above information is not intended to contain all considerations relevant to a patient's potential participation in a clinical trial.