Safety of apixaban for venous thromboembolic primary prophylaxis in patients with newly diagnosed malignant glioma.

The cumulative incidence of symptomatic venous thromboembolism (VTE) among patients with malignant gliomas (MG) is estimated to be as high as 36% during the course of therapy. Development of VTE is associated with an increased risk of hospitalization, delays in cancer treatment, and an increased risk of complications including intracranial hemorrhage as well as VTE specific symptoms. Despite the high risk of VTE and associated morbidity, there is no standard recommendations regarding long term outpatient VTE prophylaxis in patients with MG due to the lack of clinical trial evidence in this patient population. In this study, we treated ten patients with newly diagnosed MG with apixaban, 2.5 mg twice daily beginning 2-21 days after craniotomy and continuing for up to 6 months. Unacceptable toxicity was defined by ≥ grade 2 CNS or non-CNS hemorrhage, a thromboembolic event (i.e. stroke) or cardiovascular event requiring anticoagulation or anti-platelet therapy. There were no unacceptable toxicities to report and no treatment-related adverse events. None of the patients on the study were diagnosed with a VTE while receiving apixaban. We conclude that apixaban can be given safely to patients with primary MG shortly after craniotomy and should be considered for VTE prevention in these high-risk patients.