Inclusion criteria

• Confirmed diagnosis of adenocarcinoma of the prostate
• Patients with metastatic hormone refractory prostate cancer
• Patients that have had at least one, but not more than two prior cytotoxic treatments for prostate cancer

• Evidence of disease progression by at least one of the following

  1. two or more lesions on bone scan
  2. progressive measurable disease
  3. two documented increases in PSA
• Willing to use contraception throughout the study and for 12 weeks after study completion

Exclusion criteria

• History or clinical signs of CNS disease
• History of other cancers not curatively treated with no evidence of disease for more than 5 years
• Prior radiotherapy within 3 weeks of starting study treatment
• Prior radiopharmaceuticals (strontium, samarium)
• Impaired cardiac function
• Heart disease
• Liver or renal disease with impaired function

Other protocol-defined inclusion/exclusion criteria may apply