Dose-Seeking Trial of PCK3145 in Asymptomatic, Castrate Metastatic Prostate Cancer Patients.

Inclusion Criteria: * Patients who have castrate metastatic prostate cancers are eligible based on the following criteria. * Patients with prostate cancer must have castrate metastatic disease (i.e. disease progression following castration or treatment with a gonadotropin releasing hormone analog. Patients with prostate cancer may have progressing metastatic disease on imaging studies (bone scan, CT scan or MRI) in addition to a rising PSA. * Biochemical progression will be defined as: A minimum of three rising PSA values from a baseline that are obtained 1 week or more apart, or two rising PSA values more than one month apart, where the percentage increase over the range of values is at least 25%. * Maintaining castrate status: Patients who have not undergone surgical orchiectomy should continue on medical therapies \[i.e. gonadotropin releasing hormone analogs\] to maintain castrate levels of serum testosterone. Patients who are receiving an anti-androgen as part of first line hormonal therapy must have shown progression of disease off the anti-androgen prior to enrollment. * Histologically confirmed diagnosis of prostate cancer per MSKCC review. * No limitations on the duration of or number of prior therapies. * Age ≥ 18 years * Karnofsky performance status ≥ 70% (ECOG ≤ 1.0). * Life expectancy of greater than 6 months. * Hematologic: WBC ≥ 3000K/μl. * Absolute neutrophil count ≥ 1500 K/μl * Platelet count ≥ 100,000 K/μl. * Hepatic: Total Bilirubin - within normal institutional limits * AST \< 1.5 x ULN, ALT \< 1.5 x ULN. * Renal: Creatinine \< 2.0 or creatinine clearance \> 55 mL/min * Coagulation: Prothrombin time - Less than or equal to the ULN (upper limit of normal) unless patient is taking anticoagulants * Patients must have recovered from the acute toxicities of any prior therapy, and not received chemotherapy, radiation therapy or other investigational anticancer therapeutic drugs for at least 4 weeks prior to entry. * Ability to understand and the willingness to sign a written informed consent document. * Testosterone \< 50 ng/dl * Patients may be symptomatic and must be dependent on opioid analgesics or nonsteroidal anti-inflammatory drugs Exclusion Criteria: * Patients who have had chemotherapy or radiotherapy within 4 weeks prior to entering the study or those who have not recovered from the adverse events due to agents administered more than 4 weeks earlier. * Patients may not be receiving any other investigational agents. * Patients with active brain metastases or epidural disease * Uncontrolled intercurrent illness including but not limited to, ongoing or active infection, symptomatic congestive heart failure, unstable angina pectoris, cardiac arrhythmia, or psychiatric illness/social situations that would limit compliance with study requirements. * No current therapy with alternative/complementary drugs such as PC Plus, saw palmetto or Zyflamend. * No rectal bleeding except that seen following radiation proctitis or known history of hemorrhoids. * Non-prostate primary carcinoma except for non-melanoma skin cancer within previous 5 years. * No uncontrolled cardiac arrhythmias. * Patient taking steroids for cord compression or pain control are excluded. Patient on steroids for chronic conditions such as arthritis or asthma or on chronic hydrocortisone post ketoconazole will be permitted.