Magnetic Resonance Imaging in Measuring the Effect of Cabozantinib in Patients With Castrate Resistant Prostate Cancer

Inclusion Criteria:

Histologically or cytologically confirmed prostate cancer with progressive disease
Evidence of castration resistance defined as disease progression despite a testosterone level < 50ng/dL (or surgical castration)
Evidence of metastatic disease to the bones within the lumbar spine, sacrum, or pelvic bones that is identifiable on screening pelvic MRI
If patient has had prior pelvis radiation therapy (RT), then bone metastases must be out of radiated port (e.g. lumbar or sacral spine)
Any prior therapy for castrate disease acceptable other than prior XL184 with a minimum washout of 28 days for any other anticancer therapy

Patients with castrate resistant disease post antiandrogen therapy/withdrawal must meet at least one of the following criteria:

Have not received docetaxel chemotherapy
Have received docetaxel chemotherapy but received less then 225mg/m2 cumulative dose
Have documented liver metastases
Have no pain or pain that does not require a long acting (SR) narcotic
Have received mitoxantrone chemotherapy in the past for CRPC

Exclusion Criteria:

Patients who have had chemotherapy or radiotherapy within 4 weeks prior to entering the study
Patients who are receiving any other investigational agents
Prior treatment with other vascular endothelial growth factor (VEGF) or c-MET targeted therapies
History of hematemesis or hemoptysis
The subject has uncontrolled or significant intercurrent illness
The patient requires concomitant treatment, in therapeutic doses, with anticoagulants