Ibrutinib induces durable remissions in treatment-naïve patients with CLL and 17p deletion/TP53 mutations.

Ibrutinib, the first-in class Bruton's tyrosine kinase (BTK) inhibitor, has become a preferred treatment for patients with CLL, based on improved progression free and overall survival (PFS, OS) when compared to previous standard chemo-(+/-) immunotherapy regimen, in the frontline and relapsed disease settings. However, patients with 17p deletion and/or TP53 mutations were excluded from several of the pivotal CLL frontline therapy trials, and therefore there are limited data about the outcome with ibrutinib in this group of high-risk patients. Here, we report the long-term outcome of 27 patients with CLL treatment naïve with 17p deletion and/or TP53 mutation treated with ibrutinib alone or in combination with rituximab on a Phase-2 clinical study. After a median follow-up of 70 months, median PFS and OS were not reached, and the estimated 6-year PFS and OS were 60% and 79%, respectively. These data corroborate that ibrutinib therapy, induces durable remissions in patients with 17p deletion and/or TP53 mutations, and suggest that BTK inhibitor therapy should be a preferred treatment for these patients outside of clinical trials.