Australian data on the utilisation and duration on treatment of ibrutinib with a proton pump inhibitor in patients with relapsed or refractory chronic lymphocytic leukaemia.

In Australia, over half of patients with relapsed/refractory chronic lymphocytic leukaemia treated with ibrutinib use concomitant proton pump inhibitors (PPIs). High gastric pH reduces the bioavailability of some Bruton tyrosine kinase inhibitors. There was no difference in duration on ibrutinib with or without concomitant PPI (unadjusted P = 0.61; adjusted hazard ratio: 1.23, 95% confidence interval: 0.75-2.02, P = 0.411). PPI use does not affect ibrutinib treatment persistence.