TP53 and B-cell chronic lymphocytic leukemia: The 18-month PFS was 78% (72% in patients with del(17p) or TP53 mutation).33 Similarly, the combination of ibrutinib and ofatumumab (12 doses) was evaluated in 71 heavily pretreated patients with CLL/Small Lymphocytic Leukemia, 44% of whom had del(17p).