Andexanet alfa after 4-factor PCC administration for intracranial hemorrhage: a case series

[Correction of the effect of direct oral and parenteral anticoagulants in hemorrhagic stroke]

BACKGROUND

Hemorrhagic stroke is associated with high risk of adverse outcome and follows intake of anticoagulants and antiplatelet agents in 25% of cases. The latest clinical guidelines of the Neurocritical Care Society for correction (reversal) of the effect of anticoagulants and antiplatelet agents in hemorrhagic stroke were published in 2016.

MATERIAL AND METHODS

In accordance with PRISMA recommendations, we reviewed the PubMed, eLibrary and UpToDate databases to a depth of 5 years and selected 48 articles.

RESULTS AND DISCUSSION

Direct oral anticoagulants are currently common. To reverse their effect, one can use specific antidotes (idarucizumab is recommended for dabigatran, andexanet alfa (not yet registered In Russia) for factor Xa inhibitors (rivaroxaban, apixaban)) and combination of prothrombin complex concentrate and tranexamic acid. Protamine sulfate is antidote for unfractionated and low molecular weight heparins. Protamine sulfate completely inactivates unfractionated heparin, but it is less effective against low molecular weight heparin. It is characterized by high probability of anaphylactic reactions, especially after repeated administrations. The effectiveness of andexanet alpha and activated factor VII for reversing the effect of low molecular weight heparin is being studied. Fondaparinux sodium is used for heparin-induced thrombocytopenia. Protamine sulfate is ineffective for reversing the effect of fondaparinux. One can use prothrombin complex concentrate and andexanet alpha, but their effectiveness is unclear. Ciraparantag is being studied in clinical trials. Apparently, ciraparantag is highly effective as an antidote for various anticoagulants.

CONCLUSION

Early hemostatic therapy and reversal of anticoagulant effects in patients with hemorrhagic stroke significantly reduce the risk of adverse outcomes. This problem is being studied. Regular literature review with creation of updated clinical guidelines is needed.

The Incidence of Thrombotic Events After the Concomitant Use of Andexanet alfa and 4-Factor Prothrombin Complex Concentrate

Limited data exists on the safety and efficacy with the concomitant use of 4 factor prothrombic complex concentrate (4F-PCC) and andexanet alfa (AA). This case series describes 7 patients at our institution who received both 4F-PCC and AA for the management of life-threatening bleeding associated with apixaban or rivaroxaban. Four patients received AA due to worsening bleeding after 4F-PCC. Of the 7 patients in this case series, 1 had a documented thrombotic event which was an acute ischemic stroke. The thrombotic event rate in our case series was similar to the incidence of thrombotic events reported with the use of AA alone. In-hospital mortality occurred in 2 of 7 patients with 1 additional patient discharged to hospice care.

Co-administration of Four-Factor Prothrombin Complex Concentrate With Andexanet alfa for Reversal of Nontraumatic Intracranial Hemorrhage

Objective: Andexanet alfa is approved for the reversal of life-threatening or uncontrolled bleeding due to factor-Xa inhibitors. Data are limited on outcomes for patients who receive both andexanet alfa and 4-factor prothrombin complex concentrate (4F-PCC). The aim of this case series is to evaluate the safety and efficacy outcomes in patients receiving the two agents in combination. Methods: Electronic medical records of patients who received both 4F-PCC and andexanet alfa for nontraumatic intracranial hemorrhage from January 2019 to March 2022 were retrospectively reviewed. Hemostatic efficacy and complications related to concurrent use of 4F-PCC with andexanet alfa were documented. Results: Nine patients received 4F-PCC and andexanet alfa for reversal of factor Xa inhibitor-associated intracranial bleeding, eight of whom required reversal of apixaban. Of these nine patients, five patients died within 28 days for a 56% incidence of mortality. The average time from 4F-PCC administration to andexanet alfa administration was 3 hours and 9 minutes. Most doses of andexanet alfa were given for concern for bleed expansion after 4F-PCC administration. Hemostatic efficacy based on stability of repeat computed tomography scans post-administration of both agents was found in six patients (66.67%), with a 55.56% n incidence of thromboembolism, including two pulmonary embolisms, two deep vein thromboses, and one renal artery thrombosis. Conclusion: Risks and benefits should be weighed to determine if there is benefit to adding andexanet alfa to 4F-PCC in patients with incomplete hemostasis and life-threatening hemorrhage. The combination of andexanet alfa and 4F-PCC may increase the risk of thrombotic complications without improving mortality.

Antidote vs. unspecific hemostatic agents for the management of direct oral anticoagulant-related bleeding in trauma

PURPOSE OF REVIEW

The advent of direct oral anticoagulants (DOACs) marks a significant milestone in anticoagulant treatment. However, DOACs can exacerbate bleeding, which is challenging for the treating clinician, especially when combined with traumatic injury.

RECENT FINDINGS

In major bleeding associated with DOACs, rapid reversal of the anticoagulant effects is crucial. Recent observational and nonrandomized interventional trials have demonstrated the effectiveness of the specific antidotes andexanet alfa and idarucizumab as well as the unspecific prothrombin complex concentrates (PCCs) to counteract the anticoagulant effects of DOACs. The European Society of Anaesthesiology and Intensive Care guideline for severe perioperative bleeding and the European trauma guideline propose divergent recommendations for the use of andexanet alfa and PCC to obtain hemostasis in Factor Xa inhibitor-related bleeding. The conflicting recommendations are due to limited evidence from clinical studies and the potential increased risk of thromboembolic complications after the administration of andexanet. Regarding dabigatran-associated major bleeding, both guidelines recommend the specific reversal agent idarucizumab as first-line therapy.

SUMMARY

Current guidelines recommend specific antidots and PCCs in DOAC-related major bleeding. Prospective randomized trials comparing specific vs. nonspecific hemostatic agents in the perioperative setting are needed to evaluate the effectiveness and safety of the hemostatic agents.

Concomitant andexanet alfa and 4 F-PCC for Factor Xa inhibitor associated intracranial hemorrhage

Andexanet alfa is the only FDA approved drug for acute reversal of life-threatening bleeding associated with oral factor Xa inhibitor agents. The case series investigates clinical outcomes of four patients receiving concomitant Andexanet alfa and Four Factor Prothrombin Concentrate Complex (4 F-PCC) for acute reversal of intracranial hemorrhage. Following administration, effective hemostasis was achieved in two patients (50%) and one patient (25%) experienced an acute ischemic stroke. Two patients (50%) expired prior to discharge without achieving hemostasis. This case series serves to further expand the limited data on the concomitant administration of Andexanet alfa and 4 F-PCC.

Andexanet Alfa to Reverse the Effect of Factor Xa Inhibitors in Intracranial Hemorrhage

Andexanet alfa (AA) is a recombinant factor Xa competing for binding with factor Xa inhibitors, thereby reversing their anticoagulation effects. Since 2019, it has been approved for individuals under apixaban or rivaroxaban therapy suffering from life-threatening or uncontrolled bleeding. Apart from the pivotal trial, real-world data on the use of AA in daily clinics are scarce. We reviewed the current literature on patients with intracranial hemorrhage (ICH) and summarized the available evidence regarding several outcome parameters. On the basis of this evidence, we provide a standard operating procedure (SOP) for routine AA application. We searched PubMed and additional databases through 18 January 2023 for case reports, case series, studies, reviews, and guidelines. Data on hemostatic efficacy, in-hospital mortality, and thrombotic events were pooled and compared with the pivotal trial data. While hemostatic efficacy in world-wide clinical routine seems to be comparable to the pivotal trial, thrombotic events and in-hospital mortality appear to be substantially higher. Various confounding factors responsible for this finding such as exclusion and inclusion criteria resulting in a highly selected patient cohort within the controlled clinical trial have to be considered. The SOP provided should support physicians in patient selection for AA treatment as well as facilitate routine use and dosing. This review underlines the urgent need for more data from randomized trials to appreciate the benefit and safety profile of AA. Meanwhile, this SOP should help to improve frequency and quality of AA use in patients suffering from ICH while on apixaban or rivaroxaban treatment.

Reversal of apixaban and rivaroxaban with andexanet alfa prior to invasive or surgical procedures

BACKGROUND

Outcomes following andexanet alfa reversal of factor Xa inhibitors in patients requiring urgent or emergent invasive procedures are lacking. This study aimed to describe efficacy and safety outcomes following andexanet alfa administration within 24 h of an invasive procedure.

METHODS

This single-center, observational, retrospective study included patients who received andexanet alfa within 24 h of an invasive or surgical procedure. The primary outcome was hemostatic efficacy graded as excellent, good, or poor using similar definitions to the ANNEXA-4 criteria. Secondary outcomes included hospital discharge disposition, intensive care unit (ICU) and hospital length of stay, 30-day mortality, 30-day thromboischemic event rates, and serum coagulation assay changes pre- and postreversal.

RESULTS

Forty-four patients met inclusion criteria; of these, 27 (62.8%) received apixaban and 16 (37.2%) were treated with rivaroxaban prior to admission. The indications for reversal were categorized as intracranial (n = 20 [45.5%]) or extracranial (n = 24 [54.5%]) sites. Majority of patients required emergent operative procedures (18 [40.9%]), followed by invasive device placement (10 [22.7%]) or arterial embolization (9 [20.5%]). Thirty-eight (86.4%) patients were able to be adequately graded for hemostatic efficacy. Overall, 30 (78.9%) patients achieved excellent or good hemostasis within 24 h after periprocedural administration of andexanet alfa (19 [82.6%] apixaban vs. 11 [78.6%] rivaroxaban; 12 [80.0%] intracranial events vs. 18 [78.3%] extracranial events). Discharge disposition was most often to a short- or long-term care facilities (27 [61.4%]). Thirty-day mortality and thromboischemic complications occurred in 15 (34.1%) and 12 (27.3%) patients, respectively. Prothrombin time and antifactor Xa assay results were significantly decreased after andexanet alfa administration (p < 0.05) while thromboelastogram assay values (reaction time, kinetic time, and activated clotting time) showed nonsignificant changes pre- versus postreversal.

CONCLUSION

Andexanet alfa may be used for urgent or emergent reversal of apixaban and rivaroxaban peri-procedurally with promising hemostatic outcomes. Further prospective, comparative clinical research is warranted.