Evaluation of thromboembolic events in cancer patients receiving bevacizumab according to the Japanese Adverse Drug Event Report database

Purpose We aimed to examine the risk factors, time of onset, incidence rates, and outcomes of thromboembolic events induced by bevacizumab in patients with cancer using the Japanese Adverse Drug Event Report (JADER) database of the Pharmaceuticals and Medical Devices Agency. Methods Adverse event data recorded in the JADER database between January 2004 and January 2015 were used. After screening the data using the generic drug name bevacizumab, patient data were classified into two groups by age and five groups by cancer type. The histories of disorders were also categorized. Arterial thromboembolic event and venous thromboembolic event were classified as “favorable” or “unfavorable” outcomes. Results In total, 6076 patients were reported to have developed adverse events during the sample period, of which 233 and 453 developed arterial thromboembolic event and venous thromboembolic event, respectively. Logistic analysis suggested that the presence of cancer was a significant risk factor for both arterial thromboembolic event and venous thromboembolic event. Age (≥70 years), histories of either hypertension or diabetes mellitus were also risk factors for arterial thromboembolic event. Median cumulative times of onset for arterial thromboembolic event and venous thromboembolic event were 60 and 80 days, respectively, and were not significantly different by the log-rank test. By the chi-square test, the rate of unfavorable outcomes was found to be higher after developing arterial thromboembolic event than after venous thromboembolic event. Conclusion Thromboembolism is a leading cause of mortality in patients with cancer. Patients should be monitored for the symptoms of thromboembolic events right from the initial stages of bevacizumab treatment.