The present invention concerns pharmaceutical formulations of abiraterone acetate and ARN-509, which can be administered to a mammal, in particular a human, suffering from an androgen receptor (AR)-related disease or condition, in particular cancer, more in particular prostate cancer, including but not limited to castration-resistant prostate cancer, metastatic castration resistant prostate cancer, chemotherapy-naive metastatic castration resistant prostate cancer, biochemically relapsed hormone sensitive prostate cancer, or high-risk, non-metastatic castration-resistant prostate cancer. In one aspect, these formulations comprise abiraterone acetate and a solid dispersion of ARN-509 and a polymer selected from HPMCAS, a poly(meth)acrylate copolymer, and mixtures thereof. In one aspect, these formulations comprise a granulate of abiraterone acetate and a solid dispersion of ARN-509 and a polymer selected from HPMC AS, a poly(meth)acrylate copolymer, and mixtures thereof.