Incidence of cardiovascular and bleeding events and reasons for discontinuation in patients with chronic lymphocytic leukemia treated with ibrutinib-A retrospective analysis on consecutive patients from a well-defined region.

Objective: Ibrutinib treatment is associated with cardiovascular side effects, in particular atrial fibrillation (AF) and hypertension, as well as increased risk of bleeding. Here, we aimed at describing the incidence of these events during long-term follow-up in patients with chronic lymphocytic leukemia treated outside clinical trials as well as identifying clinical factors predictive of developing AF. Additionally, other reasons for treatment withdrawal were analyzed.

Methods: The study was retrospective, data were collected from medical records.

Results: A total of 134 patients were identified. Median follow-up was 32 months (range 3-103) and median duration of ibrutinib treatment was 26 months (range 1-103). Of 110 patients with no prior history of AF, 24.5% were diagnosed during treatment. Newly diagnosed or worsening of pre-existing hypertension occurred in 15.7%. Sixty-six % of the patients experienced bleeding events, of which 7.5% grade 3-4. Treatment discontinuation and dose reduction occurred in 68% and 47% of the patients, respectively, mostly due to toxicity.

Conclusions: The incidence of AF was high and at a median follow-up of 2.5 years, two-thirds of the patients discontinued treatment mostly due to bleeding and infections. Treatment-related toxicity of any grade should be regarded as a concern of prolonged ibrutinib therapy.