Compared with the anti-tumor effects of other inhibitors commonly applied in the treatment of CLL, KAN0439834 reached similar levels of apoptosis induction as venetoclax (Bcl-2 inhibitor) in patient-derived CLL cells, and was more effective than ibrutinib (BTK inhibitor) and idelalisib (PI3K inhibitor). The gene discussed is BCL2; the disease is B-cell chronic lymphocytic leukemia.