Inclusion Criteria:

- Male ≥ 20 years of age

- Histologically or cytologically confirmed adenocarcinoma of the prostate

- Presents with at least 2 bone metastases, confirmed by scintigraphic imaging within
the previous 4 weeks

- Patients who has failed initial hormonal therapy using either an orchiectomy or a
Gonadotropin releasing hormone (GnRH) agonist in combination with an antiandrogen
must first progress through antiandrogen withdrawal prior to being eligible. The
minimum timeframe to document failure of anti-androgen withdrawal will be four weeks

- Progressive castration resistant metastatic disease

- Castrate level of testosterone (<50 ng/dL), treatment to maintain castrate levels of
testosterone must be continued

Exclusion Criteria:

- Has received an investigational drug in the 4 weeks before or is scheduled to
receiving one during or in the 8 weeks after study drug administration.

- Has received chemo-, immuno-, or radiotherapy within the last 4 weeks prior to entry
in the study, or has not recovered from acute adverse events as a result of such
therapy

- Has received prior hemibody external radiotherapy

- Has a need for immediate external radiotherapy

- Has received systemic radiotherapy with radium-223, strontium-89, samarium-153,
rhenium-186 or rhenium-188 for the treatment of bony metastases within the last 24
weeks prior to administration of study drug

- When receiving bisphosphonates, has changed the dose within 4 weeks before
administration of study drug