This is a multicenter phase 2 open-label single-arm study that will evaluate the safety and efficacy of TAK-700 in patients with castration-resistant prostate cancer (CRPC) without radiographic evidence of metastases who have a rising prostate-specific antigen (PSA).

Inclusion Criteria:

Each patient must meet all of the following inclusion criteria:

• Male patients 18 years or older
• Eastern Cooperative Oncology Group performance status 0-2
• Male patients who Practice effective barrier contraception during study and for 4 months after the last dose of study drug, OR Abstain from heterosexual intercourse.
• Voluntary written consent
• Histologically or cytologically confirmed diagnosis of prostate adenocarcinoma without radiographic evidence of metastasis but with a rising PSA during or following the patient's most recent antineoplastic therapy despite castrate concentrations of testosterone
• Baseline PSA must be greater than or equal to 2 ng/mL and PSA doubling time must be less than or equal to 8 months OR baseline PSA must be greater than or equal to 8 ng/mL if PSA doubling time is greater than 8 months
• Has undergone orchiectomy or will continue receiving GnRH analogue therapy
• Meet screening laboratory values as specified in protocol

Exclusion Criteria:

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

• Known hypersensitivity to TAK-700 or related compounds
• Received any of the following within 30 days prior to the first dose of TAK-700: any investigational compound; prior herbal product known to decrease PSA; radiation therapy for prostate cancer; OR chronic therapy with corticosteroids
• Received prior therapy with aminoglutethimide or ketoconazole
• Received antiandrogen therapy within 4 weeks for flutamide and 6 weeks for all others prior to first dose of study drug
• Received prior chemotherapy for prostate cancer
• Current bladder neck outlet obstruction caused by prostate cancer, current spinal cord compression, or current bilateral hydronephrosis
• Symptoms that investigator deems related to prostate cancer
• 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
• History of adrenal insufficiency
• Uncontrolled cardiovascular condition
• Known history of human immunodeficiency virus (HIV) infection, hepatitis B, or hepatitis C
• Unwilling or unable to comply with protocol
• Major surgery or serious infection within 14 days of first dose of TAK-700
• Life-threatening illness unrelated to cancer
• Uncontrolled nausea, vomiting or diarrhea
• Known gastrointestinal disease or procedure that could interfere with oral absorption or tolerance of TAK-700