Palbociclib, a CDK4/6 inhibitor, was trialed for low-to-normal p16-expressing CH to determine progression-free survival (125 mg/day for 21/28-day cycle) [40] and efficacy via disease control rate (120 mg/day for 21/28-day cycle) [39]. This evidence concerns the gene CDK4 and cyclic hematopoiesis.