Navitoclax is a dual inhibitor of BCL-2/BCL-xL, and its application as a monotherapy in relapsed/refractory (R/R) CLL was promising, with a 35% partial response rate, though 28% of patients experienced grade 3/4 thrombocytopenia due to the requirement of BCL-xL in the development of platelets66,67. This evidence concerns the gene BCL2L1 and B-cell chronic lymphocytic leukemia.