Idarucizumab since FDA approval: Use in the real-world

A Historical Perspective on the Reversal of Anticoagulants

There has been a landmark shift in the last several decades in the management and prevention of thromboembolic events. From the discovery of parenteral and oral agents requiring frequent monitoring as early as 1914, to the development of direct oral anticoagulants (DOACs) that do not require monitoring or dose adjustment in the late 20th century, great advances have been achieved. Despite the advent of these newer agents, bleeding continues to be a key complication, affecting 2 to 4% of DOAC-treated patients per year. Bleeding is associated with substantial morbidity and mortality. Although specific reversal agents for DOACs have lagged the release of these agents, idarucizumab and andexanet alfa are now available as antagonists. However, the efficacy of these reversal agents is uncertain, and complications, including thrombosis, have not been adequately explored. As such, guidelines continue to advise the use of nonspecific prohemostatic agents for patients requiring reversal of the anticoagulant effect of these drugs. As the indications for DOACs and the overall prevalence of their use expand, there is an unmet need for further studies to determine the efficacy of specific compared with nonspecific pro-hemostatic reversal agents. In this review, we will discuss the evidence behind specific and nonspecific reversal agents for both parenteral and oral anticoagulants.

Safety of idarucizumab in the reversal of dabigatran at six tertiary care Ontario hospitals

Background

Idarucizumab, a monoclonal antibody fragment that reverses the anticoagulant effect of dabigatran, was approved for use in Canada in 2016.

Objective

Our objective was to assess the safety of idarucizumab among patients who received the drug within the first 3 years of its use in Canada.

Patients/Methods

We performed a retrospective health records review of all idarucizumab use, excluding use in those <18 years of age, between May 16, 2016, and August 1, 2019, at six Ontario tertiary care hospitals. The primary outcome was mortality. The secondary outcomes were in-hospital arterial thrombotic event (ATE), in-hospital venous thromboembolism (VTE), length of hospital stay, and length of critical care stay.

Results

A total of 85 patients received idarucizumab during the study period for the following indications: 37 (43.5%) for spontaneous bleeding, 28 (32.9%) for traumatic bleeding, 11 (12.9%) for emergency surgeries/procedures, 5 (5.9%) for elective surgeries/procedures, and 4 (4.7%) for other indications. Nineteen patients (22.4%; 95% confidence interval [CI], 14.8%-32.3%) did not survive their hospitalization. During hospitalization, two patients (2.4%; 95% CI, 0.7%-8.2%) had ATE, and three patients (3.5%; 95% CI, 1.2%-9.9%) had VTE. The median length of stay was 8 (interquartile range [IQR], 2.5-13) days in hospital and 3 (IQR, 2-5) days in critical care.

Conclusions

Compared with clinical trial data, we found a numerically higher rate of mortality and similar rate of ATE and VTE among patients treated with idarucizumab in the real world.

Use of idarucizumab in reversing dabigatran anticoagulant effect: a critical appraisal

Use of non-vitamin K antagonist oral anticoagulants is spreading in the real world. Despite that, a strong need for antidotes/reversal agents is still reported by several physicians. Idarucizumab is a humanized monoclonal antibody fragment that binds specifically to dabigatran. Idarucizumab was approved in 2015 by the US Food and Drugs Administration and European Medicines Agency for reversal of anticoagulation activity in dabigatrantreated patients. This review briefly summarizes the experimental evidence about effectiveness and safety of idarucizumab. Furthermore, we review the current recommendations and experts' point of view about the use of antidotes/reversal agents in patients reporting a major bleeding event.