TP-0903 was indeed able to inhibit AKT phosphorylation and reduced expressions of both Mcl-1 and XIAP in CLL B-cells from ibrutinib exposed patients but had no clear effect on Bcl-2 expression in sensitive patients (Figure 4E and Supplementary Figure 2B-2E). This evidence concerns the gene MCL1 and B-cell chronic lymphocytic leukemia.