This large, prospective, real-world analysis in 11,121 patients from 47 countries showed low bleeding and stroke rates in rivaroxaban-treated patients with AF, with low treatment discontinuation in different regions of the world. Results were broadly consistent across regions. (Xarelto for Prevention of Stroke in Patients With Atrial Fibrillation [XANTUS]; NCT01606995; Xarelto for Prevention of Stroke in Patients With Atrial Fibrillation in Latin America and EMEA Region [XANTUS-EL]; NCT01800006; and Xarelto for Prevention of Stroke in Patients With Atrial Fibrillation in Asia [XANAP]; NCT01750788).

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Venous thromboembolism (VTE) is associated with numerous complications and high mortality rates. Patients with cancer are at high risk of developing cancer-associated thrombosis (CAT), and VTE recurrence is common. Evidence supporting use of non-vitamin K antagonist (VKA) oral anticoagulants (NOACs) in patients with cancer is lacking - direct comparisons between NOACs and low-molecular-weight heparin (LMWH) are needed, along with patient-reported outcomes. Cancer Associated thrombosis - expLoring soLutions for patients through Treatment and Prevention with RivarOxaban (CALLISTO) is an international research programme exploring the potential of the direct, oral factor Xa inhibitor rivaroxaban for the prevention and treatment of CAT, supplementing existing data from EINSTEIN DVT and EINSTEIN PE. Here, we focus on four CALLISTO studies: A Study to Evaluate the Efficacy and Safety of Rivaroxaban Venous Thromboembolism Prophylaxis in Ambulatory Cancer Participants receiving Chemotherapy (CASSINI), Anticoagulation Therapy in SELECTeD Cancer Patients at Risk of Recurrence of Venous Thromboembolism (SELECT-D), Rivaroxaban in the Treatment of Venous Thromboembolism in Cancer Patients - a Randomized Phase III Study (CONKO-011) and a database analysis. Optimal anticoagulation duration for VTE treatment has always been unclear. Following favourable results for rivaroxaban 20 mg once-daily (Q. D.) for secondary VTE prevention (EINSTEIN EXT), EINSTEIN CHOICE is assessing rivaroxaban safety and (20 mg Q. D. or 10 mg Q. D.) vs acetylsalicylic acid (ASA), and will investigate whether an alternative rivaroxaban dose (10 mg Q. D.) could offer long-term VTE protection. It is anticipated that results from these studies will provide important answers and expand upon current evidence for rivaroxaban in VTE management.

The low rates of major bleeding and stroke in XANTUS were consistent with results from ROCKET AF. All-cause death, but not vascular death, was higher in XANTUS, as expected in an unselected real-world population.

BackgroundAround 20% of venous thromboembolism (VTE) cases occur in patients with cancer. Current guidelines recommend low molecular weight heparin (LMWH) as the preferred anticoagulant for VTE treatment. However, some guidelines state that vitamin K antagonists (VKAs) and direct oral anticoagulants (DOACs) are acceptable alternatives for long-term therapy in some patients if LMWHs are not available. LMWHs and VKAs have a number of drawbacks that can increase the burden on patients. DOACs, such as rivaroxaban, can ameliorate some burdens and may offer an opportunity to increase patient satisfaction and health-related quality of life (HRQoL). The Cancer-associated thrOmboSIs – patient-reported outcoMes with rivarOxaban (COSIMO) study is designed to provide real-world information on treatment satisfaction in patients with active cancer who switch from LMWH or VKA to rivaroxaban for the treatment of acute VTE or to prevent recurrent VTE.MethodsCOSIMO is a prospective, non-interventional, single-arm cohort study that aims to recruit 500 patients in Europe, Canada and Australia. Adults with active cancer who are switching to rivaroxaban having received LMWH/VKA for the treatment and secondary prevention of recurrent VTE for at least the previous 4 weeks are eligible. Patients will be followed for 6 months. The primary outcome is treatment satisfaction assessed as change in the Anti-Clot Treatment Scale (ACTS) Burdens score at week 4 after enrolment compared with baseline. Secondary outcomes include treatment preferences, measured using a discrete choice experiment, change in ACTS Burdens score at months 3 and 6, and change in HRQoL (assessed using the Functional Assessment of Chronic Illness Therapy – Fatigue questionnaire). COSIMO will collect data on patients’ medical history, patterns of anticoagulant use and incidence of bleeding and thromboembolic events. Study recruitment started in autumn 2016.ConclusionsCOSIMO will provide information on outcomes associated with switching from LMWH or VKA therapy to rivaroxaban for the treatment or secondary prevention of cancer-associated thrombosis in a real-life setting. The key goal is to assess whether there is a change in patient-reported treatment satisfaction. In addition, COSIMO will facilitate the evaluation of the safety and effectiveness of rivaroxaban in preventing recurrent VTE in this patient population.Trial registrationNCT02742623. Registered 19 April 2016.Electronic supplementary materialThe online version of this article (10.1186/s12959-018-0176-2) contains supplementary material, which is available to authorized users.