CD274 and acute myeloid leukemia: Although most of the clinical trials using PD-1/PD-L1 inhibitors have been administered to R/R AML patients who experienced intensive induction chemotherapy at least twice (16, 32, 43, 44), a multi-center phase 2 study (NCT02845297) of pembrolizumab (PD-1–blocking antibody) and azacitidine (AZA) in patients with R/R AML and a small cohort of newly diagnosed AML patients (median age and range: 75, 67-83 years) suggested a favorable overall response rate (ORR; 71%) and survival for newly diagnosed and unfit older AML patients.