Safety and Effectiveness of Direct Oral Anticoagulants Versus Vitamin K Antagonists: Pilot Implementation of a Near‐Real‐Time Monitoring Program in Italy

Background: Real‐time monitoring is used to the ends of postmarketing observational research on newly marketed drugs. We implemented a pilot near‐real‐time monitoring program on the test case of oral anticoagulants. Specifically, we evaluated the safety and effectiveness of direct oral anticoagulants compared to vitamin K antagonists in nonvalvular atrial fibrillation secondary prevention during 2013‐2015 in the Lazio Region, Italy. Methods and Results: A cohort study was conducted using a sequential propensity‐score–matched new user parallel‐cohort design. Sequential analyses were performed using Cox models. Overall, 10 742 patients contributed to the analyses. Compared with vitamin K antagonists, direct oral anticoagulant use was associated with a reduction of all‐cause mortality (0.81; 95% confidence interval [CI] 0.66‐0.99), cardiovascular mortality (0.71; 95% CI 0.54‐0.93), myocardial infarction (0.67; 95% CI 0.43‐1.04), ischemic stroke (0.87; 95% CI 0.52‐1.45), hemorrhagic stroke (0.25; 95% CI 0.07‐0.88), and with a nonsignificant increase of gastrointestinal bleeding (1.26; 95% CI 0.69‐2.30). Conclusions: The present pilot study is a cornerstone to develop real‐time monitoring for new drugs in our region.