WT1 and acute myeloid leukemia: Furthermore, CTLs targeting this WT1 9mer (RMFPNAPYL) on an HLA-A*02:01 molecule are one of the most common CTL types studied clinically in AML patients and have been safely employed in multiple AML clinical trials, with rare instances of graft-versus-host toxicities or on-target off-tumor side effects (11–13).