Recurrent Venous Thromboembolism in Two Patients With Cancer Taking Rivaroxaban.

Pharmacologic agents for the treatment and prevention of venous thromboembolism in the cancer patient population are limited. Currently, low-molecular-weight heparin is recommended by national consensus guidelines for this indication. Rivaroxaban, an oral factor Xa inhibitor, is Food and Drug Administration (FDA) approved for the treatment and prevention of venous thromboembolism and offers the convenience of oral fixed-dose regimens, no routine laboratory monitoring, and has few drug and dietary interactions; however, its use in patients with cancer has not been largely studied. We report 2 cases of recurrent venous thromboembolism in patients with active cancer on rivaroxaban therapy. The first case is a 64-year-old female admitted for recurrent pulmonary embolism, and the second case is a 70-year-old female admitted for recurrent deep vein thrombosis. Both patients were receiving rivaroxaban at the time of thromboembolic recurrence. These cases serve as a reminder to health-care providers that more safety and efficacy data in the cancer patient population are needed prior to using rivaroxaban for venous thromboembolism treatment.