SUMMARY: The Center for Disease Control and Prevention (CDC) estimates that approximately 1-2 per 1000 individuals develop Deep Vein Thrombosis/Pulmonary Embolism (PE) each year in the United States, resulting in 60,000 – 100,000 deaths. Venous ThromboEmbolism (VTE) is the third leading cause of cardiovascular mortality. Patients with unprovoked DVT and PE are two to four times more likely to be diagnosed with cancer within the following 12 months compared to the general population. In patients with cancer associated thrombosis, COUMADIN® (Warfarin) and XARELTO® (Rivaroxaban) are often prescribed, despite guidelines recommending Low Molecular Weight Heparin (LMWH) in this patient population.
Recently published data suggests that the rates of major bleeding, with use of XARELTO® in a highly selected group of cancer patients with venous thromboembolic disease, compared favorably with those treated with LMWH. (Mantha S, et al. 2015 ASH Annual Meeting). There is however limited data comparing the efficacy of different anticoagulants for VTE treatment in cancer patients.
The authors conducted this study in cancer patients, to compare the VTE recurrence rates, following most frequently prescribed anticoagulants in the United States. Newly diagnosed cancer patients with a first VTE, who initiated LMWH, COUMADIN® or XARELTO®, were selected using healthcare claims from the Humana database. The study population included 2,428 patients (XARELTO®: N=707; LMWH: N=660; COUMADIN® N =1,061). VTE recurrences were defined as hospitalizations with a primary diagnosis of VTE. Outpatients with a primary diagnosis of VTE were added as a sensitivity analysis to the recurrence definition.
The median duration on initial LMWH treatment was 1 month, on COUMADIN® was 3.5 months and on XARELTO® was 3 months. When compared to LMWH, VTE recurrence rates were lower with initial XARELTO® treatment at 6 months (13.2% versus 17.1%; P=0.06) and at 12 months (16.5% versus 22.2%; P=0.03). When initially treated with XARELTO®, recurrent VTE was 28% less likely than with LMWH (HR=0.72; P<0.03).
When compared to COUMADIN®, VTE recurrence rates were again lower with initial XARELTO® treatment at 6 months (13.2% versus 17.5%; P=0.02) and at 12 months (15.7% versus 19.9%; P=0.02). When initially treated with XARELTO®, recurrent VTE was 26% less likely than with COUMADIN® (HR=0.74; P<0.03). This benefit with XARELTO® when compared with LMWH and COUMADIN® users, was also noted in the sensitivity analysis.
The authors concluded that based on this real world healthcare claims data in cancer patients, XARELTO® was associated with a lower risk of recurrent VTE than LMWH or COUMADIN® and this could be a reflection of a shorter duration of treatment with LMWH and difficult therapeutic anticoagulation with COUMADIN®. Recurrent VTE in cancer patients treated with anticoagulation. Streiff MB, Milentijevic D, McCrae K, et al. J Clin Oncol 34, 2016 (suppl; abstr 10024)