The purpose of this study is to evaluate whether treatment with a new drug called ZK-Epothilone (ZK-Epo) given with prednisone in patients with androgen-independent prostate cancer, who have not had previous chemotherapy, is safe and helps to decrease PSA (Prostate-specific antigen) levels.

This study has previously been posted by Berlex, Inc. and Schering AG, Germany.Berlex, Inc. has been renamed to Bayer HealthCare Pharmaceuticals, Inc., Schering AG Germany has been renamed to Bayer Schering Pharma AG, Germany. Bayer HealthCare Pharmaceuticals, Inc.and Bayer Schering Pharma AG, Germany are the sponsors of the trial.

Inclusion Criteria:

• Must have evidence of confirmed metastatic prostate cancer
• Serum testosterone must be less than 50 ng/mL
• Disease must be progressing despite anti-androgen therapy
• PSA level must be elevated
• Additional criteria determined at screening visit

Exclusion Criteria:

• Any previous cytotoxic chemotherapy for prostate cancer
• Use of any investigational drug in the last 4 weeks
• Symptomatic brain tumors requiring radiation to the brain
• Active infection
• Additional criteria determined at screening visit