BCL2 and B-cell chronic lymphocytic leukemia: Indeed, the BH3-mimetic specific Bcl2 inhibitor venetoclax (ABT-199), designed to selectively bind and inhibit Bcl-2 protein, has been approved by the FDA for the treatment of patients who have relapsed or refractory chronic lymphocytic leukemia (CLL) with a genetic abnormality known as 17p deletion.