Patients receiving ibrutinib as treatment for a hematologic malignancy may experience a low incidence of thrombotic events, particularly venous thromboembolism (VTE), according to research published in the British Journal of Haematology.
Ibrutinib is approved for the treatment of multiple B-cell malignancies, but it is also associated with toxicities such as atrial fibrillation and bleeding. Patients with hematologic malignancies being treated with ibrutinib are generally at an increased risk for venous and arterial thrombosis (VTE). The incidence of thrombosis in patients receiving ibrutinib, however, is currently unknown.
Researchers performed a retrospective analysis of 565 patients who received ibrutinib. The median age of patients included in the analysis was 65 years, and 78 patients had a history of 99 VTE episodes. Median length of exposure to ibrutinib was 2.39 years per patient. Antiplatelet agents and anticoagulation were administered concurrently with ibrutinib to 224 and 47 patients, respectively. Median overlap of anticoagulation and ibrutinib was 59.5 days.
There were 24 acute thrombotic events in 22 patients during the treatment period, including 8 venous and 16 arterial events. Venous and arterial thrombosis developed at a median of 7.5 and 24.6 months, respectively, after initiating ibrutinib treatment.
Deep vein thrombosis accounted for 7 venous thrombotic events and was largely associated with provoking factors such as having a central line, immobilization, and hospitalization. Of the arterial thrombotic events, 6 were cerebrovascular accidents.
There were 9 bleeding events following a thrombotic event and 1 patient developed recurrent central line-associated thrombosis.
Univariable analysis revealed age and prior venous or arterial thrombosis to be associated with increased risk for VTE during ibrutinib treatment. Arterial thrombosis was associated with longer duration of malignancy and age.
The researchers noted that the incidence of thrombosis in patients receiving ibrutinib was low (3.9%), as was the rate of recurrent thrombosis. However, many patients receiving antiplatelet agents or anticoagulation still experienced bleeding events. The researchers suggested their findings could help clinicians decide whether to administer ibrutinib to patients with a history of thrombosis or atrial fibrillation.
Disclosures: Some authors have declared affiliations with the pharmaceutical industry. Please refer to the original study for a full list of disclosures.
1. Kander EM, Zhao Q, Bhat SA, et al. Venous and arterial thrombosis in patients with haematological malignancy during treatment with ibrutinib [published online September 18, 2019]. Br J Haematol. doi:10.1111/bjh.16209