Inclusion Criteria:

- Histologically or cytologically confirmed adenocarcinoma of the prostate

- Patients diagnosed with progressive bone predominant metastatic Castration-Resistant
Prostate Cancer (CRPC) /Hormone Refractory Prostate Cancer (HRPC) with at least 2
skeletal metastases on imaging with no lung, liver, and/or brain metastasis (lymph
node only metastasis is allowed) within the previous 12 weeks

- Known hormone refractory disease

- No intention to use cytotoxic chemotherapy within the next 6 months

- Either regular (not occasional) analgesic medication use for cancer related bone pain
or treatment with external bean radiation therapy (EBRT) for bone pain within
previous 12 weeks

- Age >/= 18 years

- Race is Asian

- Eastern Co-operative Oncology Group (ECOG) Performance Status (PS): 0-2

- Life expectancy >/= 6 months

- Adequate bone marrow, liver and renal function as assessed by the Laboratory required
by protocol

Exclusion Criteria:

- Treatment with an investigational drug within previous 4 weeks prior to screening, or
planned during the treatment or follow-up periods

- Eligible for docetaxel treatment, i.e. subjects who are fit enough, willing and who
are located where treatment with docetaxel is available

- Treatment with cytotoxic chemotherapy within previous 4 weeks prior to screening, or
failure to recover from adverse events due to cytotoxic chemotherapy administered
more than 4 weeks prior to screening (however ongoing neuropathy is permitted)

- Prior hemibody external radiotherapy is excluded. Subjects who received other types
of prior external radiotherapy are allowed provided that the bone marrow function is
assessed and meets the protocol requirements for hemoglobin, absolute neutrophil
count and platelets.

- Received systemic therapy radionuclides (e.g., strontium-89, samarium-153,
rhenium-186, rhenium-188, or radium-223 dichloride) for the treatment of bony
metastases

- Blood transfusion or erythropoetin stimulating agents within the previous 4 weeks
prior to screening

- Other malignancy treated within the last 3 years (except non-melanoma skin cancer or
low-grade superficial bladder cancer)

- Visceral metastases as assessed by abdominal/pelvic computed tomography (CT) or other
imaging modality

- Presence of brain metastases

- Lymphadenopathy exceeding 3 cm in short-axis diameter

- Any size pelvic lymphadenopathy if it is thought to be a contributor to concurrent
hydronephrosis

- Imminent or established spinal cord compression based on clinical findings and/or
magnetic resonance imaging (MRI). Subjects with history of spinal cord compression
should have completely recovered.

- Any other serious illness or medical condition