This study will review the safety of picoplatin, a new type of platinum drug, with docetaxel, a drug commonly used in the treatment of prostate cancer. Patients who are eligible for this study will have had a diagnosis of hormone-refractory prostate cancer that has metastasized to other areas of the body, and have not been previously treated with chemotherapy drugs. Picoplatin will be administered in combination with docetaxel and prednisone to identify the maximum tolerated dose (MTD). Patients will receive IV treatments of picoplatin with docetaxel every 3 weeks, with prednisone, 5 mg orally, twice daily.

Inclusion Criteria:

• Histologically or cytologically confirmed adenocarcinoma of the prostate.
• Radiologic evidence of metastatic disease (Jewett-Whitmore Stages D1-D2 or TNM Stage N1-3 or M1).
• Disease progression or recurrence documented by either: increasing serum PSA on three consecutive measurements each obtained at least one week apart, or findings on radiographic imaging studies.
• Non-surgically castrate subjects must be receiving androgen ablation therapy as maintenance therapy.
• Adequate hormonal therapy as documented by a castrate level of serum testosterone (all subjects without surgical castration must have a serum testosterone less than 50 ng/ml).
• At least 4 weeks must have elapsed after the withdrawal of antiandrogens (6 weeks in the case of bicalutamide).
• Age 18 years and over. Subjects older than 80 years should be entered on study only if considered "physiologically appropriate" for combination chemotherapy.
• ECOG performance score (PS) of 0 or 1.
• Stable levels of pain for at least 7 days before study entry.
• Life expectancy more than 3 months.
• At least 28 days must have elapsed since prior radiotherapy.
• At least 28 days must have elapsed since any prior investigational agent.
• Absolute neutrophil count (ANC) at least 1.5 x 10^9th/L.
• Platelet count at least 100 x 10^9th/L.
• Hemoglobin at least 10 g/dL.
• Serum AST and ALT levels ≥ 1.5 times upper limit of normal (ULN).
• Serum bilirubin ≤ ULN.
• Serum creatinine ≤ ULN.
• All subjects must agree to use appropriate birth control methods while on study and until 1 month after completion of study chemotherapy.

Exclusion Criteria:

• Prior treatment with cytotoxic agents (except estramustine), radioisotopes, or biological therapies other than hormones.
• Clinical evidence of brain or leptomeningeal metastases.
• Symptomatic peripheral neuropathy of Grade 2 or higher.
• History of another cancer within the preceding 5 years, except for superficial skin cancers.
• Known hypersensitivity to drugs formulated with Polysorbate 80.
• Prior radiotherapy that included ≥ 30% of the bone marrow (e.g., the whole of the pelvis or half of the spine).
• Uncontrolled intercurrent illness (e.g., active infection).
• Serious medical or psychiatric illness that could potentially interfere with the completion of the study treatment according to this protocol.
• History of serious cardiac disease, defined as myocardial infarction within six months of enrollment, congestive heart failure classified by the New York Heart Association as Class III or IV, uncontrolled cardiac arrhythmias, poorly controlled or unstable angina, or electrocardiographic evidence of acute ischemia.