Study Comparing Orteronel Plus Prednisone in Participants With Metastatic Castration-Resistant Prostate Cancer.

Inclusion Criteria:

Each participant must meet all of the following inclusion criteria:

- Voluntary written consent

- Male 18 years or older

- Histologically or cytologically confirmed diagnosis of prostate adenocarcinoma

- Radiograph-documented metastatic disease

- Progressive disease

- Prior surgical castration or concurrent use of an agent for medical castration

- Progressive disease during or following 1 or 2 regimens of cytotoxic chemotherapy, 1
of which must have included docetaxel. Must have received greater than or equal to
(>=) 360 milligram per square meter (mg/m^2) of docetaxel within a 6-month period.
Participants who were clearly intolerant to docetaxel or develop progressive disease
before receiving >= 360 mg/m^2 are also eligible if they have received at least 225
mg/m^2 of docetaxel within a 6-month period and meet the other study entry criteria.

- Eastern Cooperative Oncology Group (ECOG) performance status 0 to 2

- Even if surgically sterilized, participants must practice effective barrier
contraception during the entire study treatment period and for 4 months after the last
dose of study drug, OR Abstain from heterosexual intercourse

- Screening laboratory values as specified in protocol

- Stable medical condition

- Life expectancy of 6 months or more

- Participants who have had up to 2 prior chemotherapy treatments are eligible to
participate

Exclusion Criteria:

Participants meeting any of the following exclusion criteria are not to be enrolled in the
study:

- Known hypersensitivity to orteronel, prednisone or gonadotropin-releasing hormone
(GnRH) analogue

- Received prior therapy with orteronel, aminoglutethimide, ketoconazole or abiraterone

- Any other therapies for prostate cancer, except for GnRH analogue therapy, must be
discontinued 2 weeks before the first dose of study drug

- Radioisotope therapy or external beam radiation therapy within 4 weeks of first dose
of study drug

- Documented central nervous system metastases

- Treatment with any investigational compound within 30 days prior to first dose of
study drug (Participants who are in long-term follow-up following active treatment in
other trials are eligible)

- Diagnosis or treatment of another malignancy within 2 years preceding first dose of
study drug except nonmelanoma skin cancer or in situ malignancy completely resected

- Uncontrolled cardiovascular condition as specified in study protocol

- Known history of human immunodeficiency virus (HIV) infection, hepatitis B, or
hepatitis C

- Unwilling or unable to comply with protocol

- Known gastrointestinal disease or procedure that could interfere with oral absorption
or tolerance of orteronel

- Uncontrolled nausea, vomiting, or diarrhea despite appropriate medical therapy

- Prostate cancer confined to just the prostrate bed or immediate adjacent tissue