The primary goal is to prospectively estimate the median PFS of African American and Caucasian men with mCRPC taking apalutamide, abiraterone acetate, and prednisone. Secondary objectives include: PSA kinetics: to determine the duration of PSA response, time to nadir, and percent of men who achieve a PSA < 0.1; Radiographic assessments: to estimate the rate of objective response and incidence of bone flares; Safety (NCI CTC v4.0) and tolerability, particularly incidence and grade of hypertension in the two populations. This is a non-comparative pilot open-label, parallel arm, multicenter study of apalutamide and abiraterone acetate in African American and Caucasian men with mCRPC. It is anticipated that 3 additional sites will be needed to accrue 100 subjects (50 African American and 50 Caucasian) over a 24 month accrual period. The study agents will be administered at the following doses: apalutamide 240mg orally once daily, abiraterone acetate 1000mg orally once daily, and prednisone 5 mg BID in 4-week cycles throughout the treatment period. Fifty (50) patients will be enrolled in each group (African Americans and Caucasians). The proportion of patients who experience PSA decline of 30%, 50% and 90% will be estimated with exact 95% confidence intervals based on the binomial distribution will be computed. In addition, post-therapy changes in PSA will be explored as a continuous outcome. The Kaplan-Meier product limit method will be used to estimate the rPFS, biochemical PFS and overall survival distributions.
Key Inclusion Criteria
For a patient to be eligible for participation in this study, all of the following criteria must apply.
Key Exclusion Criteria
A patient will not be eligible for participation in this study if any of the following criteria apply.