DISEASE CHARACTERISTICS:

• Histologically confirmed prostate cancer, meeting the following criteria:

  • Metastatically progressive disease
  • Androgen-independent disease
• Patients whose pathology specimens are not available may be enrolled in the trial provided the patient has a clinical course consistent with prostate cancer and available documentation from an outside pathology laboratory of the diagnosis

• Must have radiographic evidence of disease by CT scan or bone scan that has continued to progress after primary treatment despite hormonal agents

  • Progression requires that a measurable lesion is expanding, new lesions have appeared, and/or the prostate-specific antigen (PSA) is continuing to rise on successive measurements

    • Patients on flutamide for the prior 6 months must have disease progression at least 4 weeks after withdrawal
    • Patients on bicalutamide or nilutamide must have progression at least 6 weeks after withdrawal

• Must have progressive disease after 1 prior cytotoxic chemotherapy but may have had no more than 1 previous cytotoxic chemotherapeutic line

  • Multiple courses of a taxane-based regimen may count as a single regimen
  • Multiple courses of a non-taxane agent or a combination chemotherapy regimen may count as a single regimen
• Patients who have not undergone bilateral surgical castration must continue suppression of testosterone production by appropriate usage of GnRH agonists
• No known active brain metastases

PATIENT CHARACTERISTICS:

Inclusion criteria:

• ECOG performance status 0-2
• Life expectancy > 3 months
• Leukocytes ≥ 3,000/μL
• Absolute neutrophil count ≥ 1,500/μL
• Platelets ≥ 100,000/μL
• Total bilirubin ≤ 1.5 times upper limits of normal (ULN) (except for patients with Gilbert disease)
• AST and ALT ≤ 2.5 times ULN
• Creatinine ≤ 1.5 times ULN OR creatinine clearance ≥ 60 mL/min
• No ongoing malignancies requiring active therapy
• Fertile patients must use effective contraception
• Must be able to swallow capsules
• Able to understand and sign an informed consent

Exclusion criteria:

• History of allergic reactions attributed to compounds of similar chemical or biologic composition to satraplatin or prednisone

• Uncontrolled intercurrent illness including, but not limited to, any of the following:

  • Ongoing or active serious infection
  • Symptomatic congestive heart failure
  • Unstable angina pectoris
  • Psychiatric illness/social situations that would limit patient compliance with study requirements
• HIV positivity

• Diseases where corticosteroids are contraindicated, (e.g. , active gastric or duodenal ulcer, or poorly-controlled insulin dependent diabetes)

  • Well-controlled insulin-dependent diabetes mellitus allowed provided the patient understands that their glucose levels will increase which will require their insulin dose to be adjusted

PRIOR CONCURRENT THERAPY:

Inclusion criteria:

• See Disease Characteristics
• Recovered from all prior therapy

• Concurrent bisphosphonates allowed provided the patient has been previously receiving that drug

  • If patients are not currently receiving bisphosphonates at the time of study enrollment, bisphosphonates may be started in course 2
• Patients who require hematopoietic growth factor support (e.g., epoetin alfa or darbepoetin), but not myeloid growth factors (i.e., filgrastim [G-CSF], sargramostim [GM-CSF], or other bone marrow stimulants) (except after course 1 if clinically indicated), NSAIDs, and other maintenance medications prior to study entry are allowed to continue their supportive therapies
• Patients on chronic stable steroids (e.g., no more than 10 mg prednisone/day) for a non-cancerous condition allowed
• Prior samarium-153 allowed

Exclusion criteria:

• Prior satraplatin or other platinum-containing compounds
• Prior radiotherapy to > 30% of the bone marrow
• Prior strontium chloride Sr 89, rhenium Re186, or rhenium Re188
• Prior major gastrointestinal surgery or pathology likely to influence absorption of oral medications (i.e., bypass surgeries, Whipple's procedure, or any surgery that would impair reliable absorption of oral drugs)
• Concurrent prophylactic growth factor support
• Concurrent anticancer treatment with chemotherapy, radiotherapy, major surgical procedures for prostate cancer, or nonprotocol-related immunotherapy
• Other concurrent investigational or commercial agents or therapies other than those used for this study with the intent to treat the patient's malignancy