Venetoclax, a ‘BH3-mimetic’ antagonist of the BCL2 anti-apoptotic protein, is currently widely used in some hematological malignancies including chronic lymphocytic leukemia (CLL), acute myeloid leukemia (AML) and mantle cell lymphoma (MCL) [1–6]. Here, BCL2 is linked to B-cell chronic lymphocytic leukemia.