Indeed, we observed that 70% of CLL patients on ibrutinib therapy (2–12 weeks) and 50% of patients on acalabrutinib (4–12 weeks) therapy had induced pAktS473 levels, and pAktS473 level recovery was also observed in MEC1 cells treated with BTK inhibitors in vitro. Here, BTK is linked to B-cell chronic lymphocytic leukemia.