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

Clinical guideline on reversal of direct oral anticoagulants in patients with life threatening bleeding

BACKGROUND

Anticoagulation is essential for the treatment and prevention of thromboembolic events. Current guidelines recommend direct oral anticoagulants (DOACs) over vitamin K antagonists in DOAC-eligible patients. The major complication of anticoagulation is serious or life-threatening haemorrhage, which may necessitate prompt haemostatic intervention. Reversal of DOACs may also be required for patients in need of urgent invasive procedures. This guideline from the European Society of Anaesthesiology and Intensive Care (ESAIC) aims to provide evidence-based recommendations and suggestions on how to manage patients on DOACs undergoing urgent or emergency procedures including the treatment of DOAC-induced bleeding.

DESIGN

A systematic literature search was performed, examining four drug comparators (dabigatran, rivaroxaban, apixaban, edoxaban) and clinical scenarios ranging from planned to emergency surgery with the outcomes of mortality, haematoma growth and thromboembolic complications. The GRADE (Grading of Recommendations, Assessment, Development and Evaluation) methodology was used to assess the methodological quality of the included studies. Consensus on the wording of the recommendations was achieved by a Delphi process.

RESULTS

So far, no results from prospective randomised trials comparing two active comparators (e.g. a direct reversal agent and an unspecific haemostatic agent such as prothrombin complex concentrate: PCC) have been published yet and the majority of publications were uncontrolled and observational studies. Thus, the certainty of evidence was assessed to be either low or very low (GRADE C). Thirty-five recommendations and clinical practice statements were developed. During the Delphi process, strong consensus (>90% agreement) was achieved in 97.1% of recommendations and consensus (75 to 90% agreement) in 2.9%.

DISCUSSION

DOAC-specific coagulation monitoring may help in patients at risk for elevated DOAC levels, whereas global coagulation tests are not recommended to exclude clinically relevant DOAC levels. In urgent clinical situations, haemostatic treatment using either the direct reversal or nonspecific haemostatic agents should be started without waiting for DOAC level monitoring. DOAC levels above 50 ng ml-1 may be considered clinically relevant necessitating haemostatic treatment before urgent or emergency procedures. Before cardiac surgery under activated factor Xa (FXa) inhibitors, the use of andexanet alfa is not recommended because of inhibition of unfractionated heparin, which is needed for extracorporeal circulation. In the situation of DOAC overdose without bleeding, no haemostatic intervention is suggested, instead measures to eliminate the DOACs should be taken. Due to the lack of published results from comparative prospective, randomised studies, the superiority of reversal treatment strategy vs. a nonspecific haemostatic treatment is unclear for most urgent and emergency procedures and bleeding. Due to the paucity of clinical data, no recommendations for the use of recombinant activated factor VII as a nonspecific haemostatic agent can be given.

CONCLUSION

In the clinical scenarios of DOAC intake before urgent procedures and DOAC-induced bleeding, practitioners should evaluate the risk of bleeding of the procedure and the severity of the DOAC-induced bleeding before initiating treatment. Optimal reversal strategy remains to be determined in future trials for most clinical settings.

ANMCO/SIMEU consensus document on the use of reversal agents for antithrombotic therapies in patients with ongoing bleeding or at high risk of haemorrhagic events

In recent decades, an incredible evolution in antithrombotic therapies used for treating patients with atherosclerosis, atrial fibrillation, and venous thromboembolism has been observed, leading to the availability of increasingly safe drugs. Nonetheless, bleeding complications remain a significant concern, with considerable health, social, and economic implications. To improve the acute management of patients experiencing or at risk for major bleeding events, specific reversal agents for antithrombotic drugs have been recently developed. While these agents demonstrate effectiveness in small-scale pharmacodynamic studies and clinical trials, it is imperative to balance the benefits of reversing antiplatelet or anticoagulant therapy against the risk of prothrombotic effects. These risks include the potential loss of antithrombotic protection and the prothrombotic tendencies associated with bleeding, major surgery, or trauma. This joint document of the Italian Association of Hospital Cardiologists (Associazione Nazionale Medici Cardiologi Ospedalieri) and the Italian Society of Emergency Medicine (Società Italiana di Medicina d'Emergenza-Urgenza) delineates the key features and efficacy of available reversal agents. It also provides practical flowcharts to guide their use in patients with active bleeding or those at elevated risk of major bleeding events.

Idarucizumab for dabigatran reversal: A systematic review and meta-analysis of indications and outcomes

BACKGROUND

Idarucizumab has been approved to reverse the anticoagulant effect of dabigatran. However, there is little knowledge of the effectiveness and safety of idarucizumab in daily practice.

AIMS

This systematic review and meta-analysis aims to evaluate the use, effectiveness and outcomes of idarucizumab.

METHODS

A systematic literature search was performed up to September 8th 2022. Original studies including patients prescribed idarucizumab, evaluating prescription indications, prescription appropriateness, haemostatic efficacy and/or the occurrence of adverse events were eligible. Case-reports and studies performed in patients ≤18 years or in healthy volunteers were excluded. Study selection and data extraction were performed by two independent reviewers. Pooled estimates were calculated using the random-effects model, after Freeman-Tukey double-arcsine transformation.

RESULTS

Thirty studies comprising 3602 patients were included. Idarucizumab was prescribed for bleeding (63.1 %, 95%CI 57.0 %-69.0 %), invasive procedures (30.5 %, 95%CI: 24.1 %-37.2 %), to enable thrombolysis (range: 2.0 %-27.3 %), dabigatran intoxication without bleeding (range: 3.6 %-7.0 %) or unspecified reasons (range: 0.4 %-18.8 %). Overall, 2.8 % (95%CI 0.5 %-6.2 %) of prescription indications were reported to be inappropriate upon post-hoc evaluation. Hemostatic effectiveness was achieved in 77.7 % (95%CI 66.7 %-87.2 %) and peri-procedural haemostasis was normal in 98.5 % (95%CI 86.6 %-100 %) of patients. The pooled incidences of all-cause mortality and thromboembolic events at any follow-up duration were 13.6 % (95%CI 9.6 %-17.9 %) and 2.0 % (95%CI 0.8 %-3.4 %), respectively.

CONCLUSION

Idarucizumab was mainly prescribed in the setting of bleeding. The reported hemostatic effectiveness was good, especially perioperatively, and the incidence of thromboembolic events was low. Patients with dabigatran-associated bleeding or requiring an urgent procedure nonetheless face a high mortality risk.

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.