Study of Ipatasertib or Apitolisib With Abiraterone Acetate Versus Abiraterone Acetate in Participants With Castration-Resistant Prostate Cancer Previously Treated With Docetaxel Chemotherapy

Inclusion Criteria

• Histologically confirmed metastatic or advanced prostate adenocarcinoma that has been previously treated with docetaxel-based therapy and has progressed during treatment of at least one hormonal therapy(prior docetaxel is not required for the safety cohort)
• Two rising PSA levels greater than or equal to (>/=) 2 ng/mL measured >/= 1 week apart or radiographic evidence of disease progression in soft tissue or bone
• Eastern Cooperative Oncology Group (ECOG) performance status of 0 or 1 at screening
• Adequate hematologic and organ function
• Documented willingness to use an effective means of contraception
• Safety cohort only: agreement to use CGM for first cycle of treatment

Exclusion Criteria

• History of Type I or Type II diabetes mellitus requiring insulin; safety cohort: patients who are receiving any pharmacologic treatment for diabetes are not eligible
• New York Heart Association Class III or IV heart failure or Left ventricular ejection fraction < 50% or ventricular arrhythmia requiring medication
• Significant atherosclerotic disease, as evidenced by: unstable angina, history of myocardial infarction within 6 months prior to Day 1, or cerebrovascular accident within 6 months prior to Day 1
• Active autoimmune disease that is not controlled by nonsteroidal anti-inflammatory drugs or active inflammatory disease which requires immunosuppressive therapy
• Clinically significant history of liver disease
• History of adrenal insufficiency or hyperaldosteronism
• Phase II only: Previous therapy for prostate cancer with 17 alpha-hydroxylase/C17,20-lyase inhibitors, including abiraterone
• Phase II only: Previous treatment for prostate cancer with Protein kinase B phosphatidylinositol 3 kinase and/or mammalian target of rapamycin inhibitors
• Need for chronic corticosteroid therapy of >/= 20 mg of prednisone per day or an equivalent dose of other anti inflammatory corticosteroids or immunosuppressant