Inclusion Criteria:

- at least 18 yrs of age

- diagnosis of adenocarcinoma of the prostate

- no detectable metastatic disease as assessed by bone and CT scans

- has increasing serum PSA concentrations

- life expectancy of at least 3 months

- ECOG of 0 or 1

- has been withdrawn from antiandrogen therapy for at least 6 weeks prior to entering
screening period

Exclusion Criteria:

- has asymptomatic disease

- has active GI ulceration or bleeding

- has been treated with non-hormonal systemic anticancer therapy or has received
radiation within 4 weeks of baseline visit

- bilirubin >2x ULN or ALT or AST >2xULN or serum creatinine >1.5mg/dL

- hemoglobin <9g/dL or platelets below 100,000/uL or ANC below 1500/uL

- receiving treatment for HIV with protease inhibitors

- has had prior malignancy within past 5 yrs with exception of resected basal or
squamous cell carcinomas of the skin

- has used investigational drug with previous one month