The most common grade 3-4 adverse events of special interest were cardiac disorders ( 41 [ 8 % ] of 542 patients in the abiraterone acetate group vs 20 [ 4 % ] of 540 patients in the placebo group ) , increased alanine aminotransferase ( 32 [ 6 % ] vs four [ < 1 % ] ) , and hypertension ( 25 [ 5 % ] vs 17 [ 3 % ] ) .