CDK4 and acute myeloid leukemia: This drug appears to be generally well-tolerated in hematologic malignancies, although the efficacy of the single agent seems to be minimal in the context of relapse/refractory MLL-r AML.75-77 Still, the preclinical evidence suggests that combinatory treatment with menin and CDK4/6 inhibitors may be more effective in AML than monotherapy and supports the initiation of future studies exploring the potential of these combinations in improving patient clinical outcomes.