Effectiveness and Safety of Rivaroxaban in Patients With Cancer-Associated Venous Thrombosis.

Background: Although not designated as guideline-recommended first-line anticoagulation therapy, patients are receiving rivaroxaban for the treatment and secondary prevention of cancer-associated venous thrombosis (CAT). We sought to estimate the cumulative incidence of recurrent venous thromboembolism (VTE), major bleeding, and mortality/hospice care in patients with CAT treated with outpatient rivaroxaban in routine practice. Methods: Using US MarketScan claims data from January 2012 through June 2015, we identified adults with active cancer (using SEER program coding) who had ≥1 primary hospitalization or emergency department discharge diagnosis code for VTE (index event) and received rivaroxaban as their first outpatient anticoagulant within 30 days of the index VTE. Patients were required to have ≥180 days of continuous medical/prescription benefits prior to the index VTE. Patients with a previous claim for VTE, atrial fibrillation, or valvular disease or receiving anticoagulation during the baseline period were excluded. We estimated the cumulative incidence with 95% CIs of recurrent VTE, major bleeding, and mortality or need for hospice care at 180 days, assuming competing risks. Results: A total of 949 patients with active cancer were initiated on rivaroxaban following their index VTE. Time from active cancer diagnosis to index CAT was ≤90 days for 27% of patients, 91 to 180 days for 19%, and >180 days for 54%. The mean [SD] age of patients was 62.5 [12.8] years, 43.6% had pulmonary embolism, and metastatic disease was present in 42.6%. During follow-up, there were 37 cases of recurrent VTE, 22 cases of major bleeding (17 gastrointestinal, 3 intracranial, 1 genitourinary, and 1 other bleed), and 105 deaths/hospice claims. The cumulative incidence estimate was 4.0% (95% CI, 2.8%-5.4%) for recurrent VTE, 2.7% (95% CI, 1.7%-4.0%) for major bleeding, and 11.3% (95% CI, 9.2%-13.6%) for mortality/hospice care. Conclusions: Event rates observed in this rivaroxaban-treated cohort were overall consistent with previous studies of patients with rivaroxaban- and warfarin-managed CAT.

Duke Scholars

Author Gary Herbert Lyman Medicine, Medical Oncology