Inclusion Criteria:

- Histologically or cytologically confirmed adenocarcinoma of the prostate

- Clinical or radiologic evidence of metastatic disease

- Documented disease progression during hormone therapy (ADT plus antiandrogen) and no
response to ADT withdrawal

- Docetaxel-refractory disease defined as disease progression documented either during
treatment of within 60 days after the cessation of treatment with docetaxel

- Prior exposure to estramustine or mitoxantrone is allowed

- KPS ≥ 60

- No prior radioisotope therapy

- No prior radiotherapy 25% or more of the bone marrow

- No peripheral neuropathy grade 2 or worse

- Adequate organ and bone marrow function

Exclusion Criteria:

- Other tumor type than adenocarcinoma

- Presence or history of CNS metastasis

- Other serious illness or medical conditions