Inclusion Criteria:

• Adenocarcinoma of the prostate with radiographic evidence of metastatic disease.
• Willingness to undergo a baseline tumor biopsy.
• Castrate levels of testosterone (testosterone < 50 ng/dL) on androgen deprivation therapy (ADT) with evidence of progression on ADT. GnRH therapy will be continued for those on it at baseline
• Patient must have suspected tumor in an area that is safe to biopsy.
• Other prior hormonal interventions or experimental approaches are allowed. These therapies must have been discontinued for a minimum of 28 days with cancer progression.
• Prior or concurrent use of bisphosphonates is allowed.
• One prior non-taxane chemotherapy allowed
• ≥ 3 weeks since major surgery; ≥ 4 weeks since radiotherapy; ≥ 8 weeks since prior strontium-89 or samarium 153
• Performance Status: ECOG 0 or 1
• ANC > 1,500/_l; platelets > 100,000/_l; total Bilirubin < upper limit of normal; AST and ALT < 3 x upper limits of normal; creatinine < 1.5 x upper limits of normal; total fasting cholesterol < 350 mg/dl; total triglycerides < 300 mg/dl

Exclusion Criteria:

• Ongoing oral steroid use. Patients with a history of oral steroid use are eligible as long as the steroids have been discontinued prior to study entry. Ongoing topical and/or inhaled steroid use is allowed.
• Prior taxane chemotherapy
• Prior mTOR inhibitors (RAD001, rapamycin, CCI-779)
• Currently active second malignancy other than non-melanoma skin cancer.
• Ongoing peripheral neuropathy of Grade 2