The purpose of this first-in-man study is to evaluate safety and tolerability of ODM-208 in patients with metastatic castration-resistant prostate cancer.

Safety and tolerability profile of ODM-208 will be explored

Main Inclusion Criteria:

• Written informed consent (IC) obtained.
• Male aged ≥ 18 years.
• Histologically confirmed adenocarcinoma of the prostate.
• Castration resistant prostate cancer with serum testosterone < 50 ng/dl.
• Metastatic disease.
• Ongoing androgen deprivation therapy with GnRH analogue or antagonist, or have had bilateral orchiectomy.
• Received at least one prior line of novel hormonal androgen receptor (AR) targeted therapy (e.g. abiraterone, enzalutamide).
• ECOG performance status 0-1.
• Adequate marrow, liver and kidney function.
• Able to swallow study treatment.
• Part 1: Treatment with at least 1 line of chemotherapy or ineligibility for chemotherapy. Part 2: Treatment with at least 1 line of taxane-based chemotherapy in castration-sensitive prostate cancer (CSPC) or in CRPC.

Main Exclusion Criteria:

• History of pituitary or adrenal dysfunction.
• Known brain metastases or active leptomeningeal disease.
• Active infection or other medical condition that would make corticosteroid contraindicated.
• Poorly controlled diabetes.
• Hypotension or uncontrolled hypertension.
• Clinically significantly abnormal serum potassium or sodium level.
• Active or unstable cardio/cerebro-vascular disease including thromboembolic events.
• Prolonged QTcF interval.