NOAC in patients with VTE and polycythemia vera or essential thrombocythemia: a cohort study

Thrombosis is the most common adverse event in patients with polycythemia vera (PV) and essential thrombocythemia (ET). Little is known about the use of non-vitamin K antagonist oral anticoagulants (NOACs) in patients with myeloproliferative neoplasms (MPN). We sought to evaluate the efficacy and safety of NOAC in a cohort of patients with PV and ET, who experienced venous thromboembolism (VTE). We enrolled 48 consecutive patients with PV (70.8%) and ET (median age 67.0 [IQR, 58.5-72.0] years), who experienced VTE. Patients received apixaban (39.6%), rivaroxaban (33.3%), or dabigatran (27.1%). During a median follow-up of 30 (IQR, 20.5 – 41.5) months, recurrent thrombotic events and bleeding were recorded. Four thrombotic events (3.3 per 100 patient-years) were reported. Three DVT episodes (2.5 per 100 patient-years) experienced two patients with PV who received apixaban (5 mg bid) and dabigatran (150 mg bid) and one with ET, who received dabigatran (150 mg bid). One ischemic stroke occurred in a patient with PV on rivaroxaban (20 mg/d). There was one major bleeding (0.8 per 100 patient-years) in a patient with ET on dabigatran (150 mg bid) and three clinically relevant non-major bleeding (2.5 per 100 patient-years): two on rivaroxaban (20 mg/d) and one on apixaban (5 mg bid). We did not observe significant differences related to the type of NOAC. Three deaths (2.5 per 100 patient-years) unrelated to either VTE or bleeding were recorded. This study shows that NOACs may be effective and safe as secondary prevention of VTE in patients with MPN.