BCL2 and B-cell chronic lymphocytic leukemia: Nine treatment classes were used to treat double‐exposed CLL/SLL patients including noncovalent BTKi (ncBTKi), CAR‐T cell therapy, bispecific CD20‐directed CD3 T‐cell engager, BTKi, PI3Ki, allogeneic stem cell transplantation (AlloSCT), BCL2 inhibitor retreatment, CIT, and BTKi combination therapy.