PDCD1 and acute myeloid leukemia: Currently, several clinical trials using PD-1 inhibitors in combination with ipilimumab or hypomethylating agents are ongoing in AML patients (NCT02275533, NCT02532231, NCT02464657, NCT02397720, NCT03092674, NCT02768792, NCT02845297, NCT02996474, NCT02708641, NCT02771197, NCT02775903, NCT02892318).