Factor Xa Inhibitor-Related Intracranial Hemorrhage

Long-Term Safety of a Four-Factor Prothrombin Complex Concentrate (Kcentra®/Beriplex® P/N): An Updated Pharmacovigilance Review

INTRODUCTION

 Four-factor prothrombin complex concentrate (4F-PCC) is recommended for vitamin K antagonist reversal in patients with major bleeding or in need of surgery. The most important risk associated with the use of 4F-PCC is the occurrence of thromboembolic events (TEEs). In this review, we aim to evaluate the safety profile of a 4F-PCC (Kcentra®/Beriplex® P/N; CSL Behring, Marburg, Germany) by reviewing pharmacovigilance data.

METHODS

 A retrospective analysis of postmarketing pharmacovigilance data of Kcentra®/Beriplex® P/N from February 1996 to April 2022 was performed and complemented by a review of clinical studies published between January 2012 and April 2022.

RESULTS

 A total of 2,321,443 standard infusions of Kcentra®/Beriplex® P/N were administered during the evaluation period. Adverse drug reactions (ADRs) were reported in 614 cases (∼1 per 3,781 standard infusions) and 233 of these cases (37.9%) experienced suspected TEEs related to 4F-PCC (∼1 per 9,963 standard infusions); most of these cases had pre-existing or concomitant conditions likely to be significant risk factors for thrombosis. TEE rates were similar when 4F-PCC was used on-label or off-label for direct oral anticoagulant-associated bleeding. Thirty-six cases (5.9%) reported hypersensitivity type reactions (∼1 per 64,485 standard infusions). No confirmed case of viral transmission related to 4F-PCC use was reported. The published literature also revealed a favorable safety profile of 4F-PCC.

CONCLUSION

 Analysis of postmarketing pharmacovigilance safety reports demonstrated that treatment with 4F-PCC was associated with few ADRs and a low rate of TEEs across multiple indications and settings, thus confirming a positive safety profile of 4F-PCC.

Characterizing redundancy in pharmacy residency research projects

PURPOSE

Each year, roughly 5,000 residents conduct research on clinical and practice-based topics to meet the requirements of the ASHP residency standards related to research and project management. Several investigators have evaluated residency research project publication rates, but redundancy among projects has not been evaluated. The primary objective of this study was to determine the rate of redundancy among pharmacy residency research projects.

METHODS

This was a retrospective cohort analysis of abstracts accepted to various regional pharmacy residency conferences from 2017 through 2020. Each abstract was placed in a pharmacy domain by therapeutic area. The categorized data for each year were then further evaluated to identify clinical categories for the year. Topics were labeled as redundant if at least 10 projects fell into the same focus area within a clinical category. Descriptive statistics were used to quantify the incidence of redundancy each year.

RESULTS

A total of 4,027 abstracts were included. The most common pharmacy domains were infectious disease, internal medicine, and benefit of pharmacy services. Overall, 8.2% projects (332 of 4,027) were categorized as redundant. The most common focus areas were rapid diagnostics, opioid reduction protocols, and vancomycin area-under-the-curve vs trough monitoring.

CONCLUSION

Pharmacy residency research projects encompassed topics across a wide range of pharmacotherapy areas. Approximately 1 in 12 projects was redundant. This is likely because the project addressed a "hot topic" in practice and may represent an opportunity for institutions to collaborate to optimize project efficiency and impact.

The Effect of 4-Factor Prothrombin Complex Concentrate to Reverse Factor Xa Inhibitors in Patients With Traumatic Intracranial Hemorrhage

The utility of 4-factor prothrombin complex concentrate (4F-PCC) for reversal in patients on factor Xa inhibitors (XaI) is unclear, specifically in mild traumatic brain injury (mTBI). This is a retrospective review over 6 years at a level 1 trauma center of patients presenting with mTBI on XaI comparing outcomes for those that received 4F-PCC to those that did not. 140 patients were included, 103 (74%) of these patients received 4F-PCC while 37 (26%) did not. There was no significant difference in neurologic decline within 48 hours of admission or need for neurosurgical intervention. Interestingly, there was no difference in ICH progression (16% vs 14%, P = .77). In this study, 4F-PCC given after mild traumatic brain injury did not impact ICH progression, neurologic decline, or need for neurosurgical intervention. Although limited in numbers, this study suggests that 4F-PCC is not necessarily required in mTBI and further studies are indicated.

Stroke

Stroke affects up to one in five people during their lifetime in some high-income countries, and up to almost one in two in low-income countries. Globally, it is the second leading cause of death. Clinically, the disease is characterised by sudden neurological deficits. Vascular aetiologies contribute to the most common causes of ischaemic stroke, including large artery disease, cardioembolism, and small vessel disease. Small vessel disease is also the most frequent cause of intracerebral haemorrhage, followed by macrovascular causes. For acute ischaemic stroke, multimodal CT or MRI reveal infarct core, ischaemic penumbra, and site of vascular occlusion. For intracerebral haemorrhage, neuroimaging identifies early radiological markers of haematoma expansion and probable underlying cause. For intravenous thrombolysis in ischaemic stroke, tenecteplase is now a safe and effective alternative to alteplase. In patients with strokes caused by large vessel occlusion, the indications for endovascular thrombectomy have been extended to include larger core infarcts and basilar artery occlusion, and the treatment time window has increased to up to 24 h from stroke onset. Regarding intracerebral haemorrhage, prompt delivery of bundled care consisting of immediate anticoagulation reversal, simultaneous blood pressure lowering, and prespecified stroke unit protocols can improve clinical outcomes. Guided by underlying stroke mechanisms, secondary prevention encompasses pharmacological, vascular, or endovascular interventions and lifestyle modifications.

Effect of low- versus high-dose 4-factor prothrombin complex concentrate in factor Xa inhibitor-associated bleeding: A qualitative systematic review

PURPOSE

The purpose of this review is to evaluate current literature on the treatment of factor Xa inhibitor-associated bleeds with 4-factor prothrombin complex concentrate (4F-PCC), with a focus on the effect of low versus high dosing of 4F-PCC on hemostatic efficacy and safety outcomes.

SUMMARY

A search of PubMed and EBSCOhost was performed to identify studies evaluating patients with a factor Xa inhibitor-bleed treated with 4F-PCC at either low or high doses. Studies of patients receiving alternative reversal agents such as fresh frozen plasma and andexanet alfa or where no comparator group was evaluated were excluded from the analysis. To assess the effect of these 4F-PCC dosing strategies, the primary outcome of interest was hemostatic efficacy. Four studies meeting inclusion criteria were included in this review. In each of the included studies, similar rates of hemostatic efficacy, hospital mortality, and venous thromboembolism were observed in the low- and high-dose cohorts.

CONCLUSION

These results suggest low- and high-dose 4F-PCC may confer similar clinical effectiveness and safety; however, these findings should be evaluated and confirmed with future prospective studies.

Idarucizumab in dabigatran-treated patients with acute stroke: a review and clinical update

Idarucizumab is an antibody fragment specific for the immediate reversal of dabigatran anticoagulation effects. The use of idarucizumab is approved for dabigatran-treated patients suffering from life-threatening or uncontrolled bleeding and those in need of urgent surgery or invasive procedures. Data from randomized controlled clinical trials and real-world experience provide reassuring evidence about the efficacy and safety of idarucizmab use in patients with acute stroke. In this narrative review, we summarize the available real-world evidence and discuss the relevance and importance of idarucizumab treatment in acute stroke patients in everyday clinical practice. In addition, we also discuss special issues like prothrombin complex concentrate application as an alternative to idarucizumab, its application before endovascular therapy, sensitivity of thrombi to lysis, and necessary laboratory examinations.

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.

Reversal and resumption of anticoagulants in patients with anticoagulant-associated intracerebral hemorrhage

The use of anticoagulants has become more frequent due to the progressive aging population and increased thromboembolic events. Consequently, the proportion of anticoagulant-associated intracerebral hemorrhage (AAICH) in stroke patients is gradually increasing. Compared with intracerebral hemorrhage (ICH) patients without coagulopathy, patients with AAICH may have larger hematomas, worse prognoses, and higher mortality. Given the need for anticoagulant reversal and resumption, the management of AAICH differs from that of conventional medical or surgical treatments for ICH, and it is more specific. Understanding the pharmacology of anticoagulants and identifying agents that can reverse their effects in the early stages are crucial for treating life-threatening AAICH. When patients transition beyond the acute phase and their vital signs stabilize, it is important to consider resuming anticoagulants at the right time to prevent the occurrence of further thromboembolism. However, the timing and strategy for reversing and resuming anticoagulants are still in a dilemma. Herein, we summarize the important clinical studies, reviews, and related guidelines published in the past few years that focus on the reversal and resumption of anticoagulants in AAICH patients to help implement decisive diagnosis and treatment strategies in the clinical setting.

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.

Reversal of pre-injury factor-Xa inhibitors with prothrombin complex concentrates in patients following traumatic brain injury

INTRODUCTION

There is substantial debate on the best method to reverse factor Xa-inhibitors in patients following traumatic brain injury (TBI). Prothrombin complex concentrates (PCC) have been used for this indication but their role has been questioned. This study reported failure rates with PCC in patients following TBI and as a secondary objective, compared 4-factor (4 F-PCC) and activated PCC (APCC).

MATERIAL AND METHODS

Consecutive patients with TBI on factor Xa-inhibitors admitted to one of two trauma centers were retrospectively identified. Patients with penetrating TBI, delays in PCC administration (>6 h), receipt of tranexamic acid, factor VIIa or no follow up CT-scan were excluded. The primary outcome was treatment failure defined as hematoma expansion > 20% from baseline for SDH, EDH or IPH, a new hematoma not present on the initial CT scan or any expansion of a SAH or IVH. Hematoma expansion was further categorized as symptomatic or asymptomatic, designated by a change in the motor GCS score, neurologic exam or change ≥ 3 in NIH Stroke Scale. Multi-variate analysis was performed.

RESULTS

There were 43 patients with a mean age of 77 ± 13 years with primarily mild TBI (95%) after a ground level fall (79%). The mean dose was 41 ± 12 units/kg. Sixty percent received 4 F-PCC and 40% APCC. The incidence of treatment failure was 28% (12/43). Of the 12 patients with hematoma expansion, only 3 were symptomatic (9.3%). Hematoma expansion with 4 F-PCC and APCC were similar (27% vs. 29%,p = .859). Only sex was associated with hematoma expansion on multivariate analysis [OR (95% CI) = 6.7 (1.1 - 40.9)].

CONCLUSION

PCC was an effective option for factor Xa inhibitor reversal following TBI. The relationship between radiographic expansion and clinical expansion was poor.

Urine-derived cells from the aged donor for the 2D/3D modeling of neural cells via iPSCs

Human neural cell models derived from induced pluripotent stem cells (iPSCs) have been widely accepted to model various neurodegenerative diseases such as Alzheimer's disease (AD) in vitro. Although the most common sources of iPSCs are fibroblasts and peripheral blood mononuclear cells, the collection of these cells is invasive. To reduce the donor's burden, we propose the use of urine-derived cells (UDCs), which can be obtained non-invasively from a urine sample. However, the collection of UDCs from elderly donors suffering from age-related diseases such as AD has not been reported, and it is unknown whether these UDCs from the donor aged over 80 years old can be converted into iPSCs and differentiated into neural cells. In this study, we reported a case of using the UDCs from the urine sample of an 89-year-old AD patient, and the UDCs were successfully reprogrammed into iPSCs and differentiated into neural cells in four different ways: (i) the dual SMAD inhibition with small-molecules via the neural progenitor precursor stage, (ii) the rapid induction method using transient expression of Ngn2 and microRNAs without going through the neural progenitor stage, (iii) the cortical brain organoids for 3D culture, and (iv) the human astrocytes. The accumulation of phosphorylated Tau proteins, which is a pathological hallmark of AD, was examined in the neuronal models generated from the UDCs of the aged donor. The application of this cell source will broaden the target population for disease modeling using iPS technology.

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.

Hemostatic efficacy of four factor prothrombin complex concentrate in intracerebral hemorrhage patients receiving warfarin vs. factor Xa inhibitors

INTRODUCTION

4-F PCC is administered for reversal of factor Xa inhibitor-associated coagulopathy despite a lack of quality evidence demonstrating hemostatic efficacy. The aim of this study was to evaluate the hemostatic efficacy of 4-F PCC in intracerebral hemorrhage patients who received factor Xa inhibitors versus warfarin.

MATERIALS AND METHODS

This was a multi-center, retrospective, observational cohort study at a large healthcare system. Patients taking warfarin received 4-F PCC 25-50 units/kg based on the presenting INR, while patients taking a factor Xa inhibitor received 35 units/kg. The primary outcome was the percentage of patients with good or excellent hemostatic efficacy as assessed by modified Sarode scale, with neurologic outcomes assessed as a secondary endpoint. Patients were included in the primary outcome population if they had a repeat CT scan within 24 h.

RESULTS

One hundred fifty-seven patients were included in the primary outcome population; [warfarin (n = 76), factor Xa inhibitors (n = 81)]. Hemostatic efficacy was 83 % in the warfarin group versus 75 % in the factor Xa inhibitor group (p = 0.24). The hemostatic efficacy risk difference between the groups was 7.6 % (95 % CI 5.1 %, 20.2 %). Good neurologic outcome (mRS 0-2) at discharge was 17 % in warfarin patients versus 12 % in the factor Xa inhibitor patients (p = 0.40).

CONCLUSIONS

There was no significant difference in hemostatic efficacy or clinical outcomes between patients taking warfarin or a factor Xa inhibitor following reversal with 4-F PCC. This study provides further support that 4-F PCC can be used for the reversal of factor Xa inhibitor-associated coagulopathy.

Clinical Relevance of Preclinical and Clinical Studies of Four-Factor Prothrombin Complex Concentrate for Treatment of Bleeding Related to Direct Oral Anticoagulants

Direct oral anticoagulants (DOACs) are widely used for the prevention and treatment of venous thromboembolism and stroke. When emergency reversal of DOAC-related anticoagulation is required, specific DOAC reversal agents are recommended, including idarucizumab for dabigatran reversal and andexanet alfa for apixaban and rivaroxaban reversal. However, specific reversal agents are not always available, andexanet alfa has not been approved for urgent surgery, and clinicians need to know the patient's anticoagulant medication before administering these treatments. Four-factor prothrombin complex concentrates (4F-PCCs) are recognized as nonspecific, alternative hemostatic agents for treatment of DOAC-related bleeding. Evidence from preclinical and clinical studies shows that they may reduce the anticoagulant effects of DOACs and may help control DOAC-related bleeding. However, randomized controlled trials are lacking, and most data are from retrospective or single-arm prospective studies in bleeding associated with activated factor X inhibitors. There are no clinical data showing the efficacy of 4F-PCC for the treatment of bleeding in dabigatran-treated patients. This review focuses on the current evidence of 4F-PCC use in controlling bleeding associated with DOACs and provides an expert opinion on the relevance of these data for clinical practice. The current treatment landscape, unmet needs, and future directions are also discussed.

Clinical Performance Measures for Emergency Department Care for Adults With Intracranial Hemorrhage

Though select inpatient-based performance measures exist for the care of patients with nontraumatic intracranial hemorrhage, emergency departments lack measurement instruments designed to support and improve care processes in the hyperacute phase. To address this, we propose a set of measures applying a syndromic (rather than diagnosis-based) approach informed by performance data from a national sample of community EDs participating in the Emergency Quality Network Stroke Initiative. To develop the measure set, we convened a workgroup of experts in acute neurologic emergencies. The group considered the appropriate use case for each proposed measure: internal quality improvement, benchmarking, or accountability, and examined data from Emergency Quality Network Stroke Initiative-participating EDs to consider the validity and feasibility of proposed measures for quality measurement and improvement applications. The initially conceived set included 14 measure concepts, of which 7 were selected for inclusion in the measure set after a review of data and further deliberation. Proposed measures include 2 for quality improvement, benchmarking, and accountability (Last 2 Recorded Systolic Blood Pressure Measurements Under 150 and Platelet Avoidance), 3 for quality improvement and benchmarking (Proportion of Patients on Oral Anticoagulants Receiving Hemostatic Medications, Median ED Length of Stay for admitted patients, and Median Length of Stay for transferred patients), and 2 for quality improvement only (Severity Assessment in the ED and Computed Tomography Angiography Performance). The proposed measure set warrants further development and validation to support broader implementation and advance national health care quality goals. Ultimately, applying these measures may help identify opportunities for improvement and focus quality improvement resources on evidence-based targets.

Deterioration free discharge comparison of andexanet-alfa and prothrombin complex concentrates (PCC) for reversal of factor Xa inhibitor associated bleeds

Given the paucity of comparative efficacy data and the difference in cost between andexanet-alfa and prothrombin complex concentrates (PCC), debates continue regarding optimal cost-effective therapy for patients who present with major bleeding associated with oral factor Xa inhibitors. Available literature comparing the cost-effectiveness of the reversal agents is limited, and the large difference in price between therapy options has led many health systems to exclude andexanet-alfa from their formularies. To evaluate the clinical outcomes and cost of PCC compared to andexanet-alfa for patients with factor Xa inhibitor associated bleeds. We performed a quasi-experimental, single health system study of patients treated with PCC or andexanet-alfa from March 2014 to April 2021. Deterioration-free discharge, thrombotic events, length of stay, discharge disposition, and cost were reported. 170 patients were included in the PCC group and 170 patients were included in the andexanet-alfa group. Deterioration-free discharge was achieved in 66.5% of PCC-treated patients compared to 69.4% in the andexanet alfa-treated patients. 31.8% of PCC-treated patients were discharged home compared to 30.6% in the andexanet alfa-treated patients. The cost per deterioration-free discharge was $20,773.62 versus $5230.32 in the andexanet alfa and 4 F-PCC group, respectively. Among patients that experienced a bleed while taking a factor Xa inhibitor, there was no difference in clinical outcomes for patients treated with andexanet-alfa compared to PCC. Although there was no difference in the clinical outcomes, there was a significant difference in cost with andexanet-alfa costing approximately four times as much as PCC per deterioration-free discharge.

Real-world clinical outcomes among US Veterans with oral factor xa inhibitor-related major bleeding treated with andexanet alfa or 4-factor prothrombin complex concentrate

Oral factor Xa (FXa) inhibitors significantly reduce incidence of stroke and thromboembolic events in patients with atrial fibrillation or venous thromboembolism. Due to various factors and the lack of a randomized controlled trial comparing andexanet alfa to usual care, non-specific replacement agents including 4 F-PCC are still used off-label for FXa inhibitor bleed management. Clinical and mortality data were extracted from the inpatient medical data and Veteran Affairs (VA) vital status files over the time of March 2014 through December 2020. Propensity score-weighted models were used for this retrospective cohort study using data from the Veterans Affairs Informatics and Computing Infrastructure (VINCI). The study included 255 patients (85-andexanet alfa and 170-4 F-PCC) exposed to an oral factor Xa inhibitor and hospitalized with an acute major, gastrointestinal (GI), intracranial (ICH) or other bleed. In-hospital mortality was significantly lower in the andexanet alfa cohort compared to the 4 F-PCC cohort (10.6% vs. 25.3%, p = 0.01). Propensity score-weighted Cox models reveal a 69% lower hazard of in-hospital mortality for those treated with andexanet alfa (HR 0.31, 95% CI 0.14-0.71) compared to those treated with 4 F-PCC. Additionally, those treated with andexanet alfa had a lower 30-day mortality rate and lower 30-day hazard of mortality in the weighted Cox model (20.0% vs. 32.4%, p = 0.055; HR 0.54, 95% CI 0.30-0.98) compared to those treated with 4 F-PCC. Among 255 US veterans with major bleeding in the presence of an oral factor Xa inhibitor, treatment with andexanet alfa was associated with lower in-hospital and 30-day mortality than treatment with 4 F-PCC.

The use of andexanet alfa and 4-factor prothrombin complex concentrate in intracranial hemorrhage

OBJECTIVE

to describe the clinical and safety outcomes between andexanet alfa (AA) and 4-factor prothrombin complex concentrate (4F-PCC) for the reversal of apixaban or rivaroxaban in the setting of an intracranial hemorrhage (ICH).

METHODS

A retrospective, multicentered descriptive study was conducted in hospitalized patients 18 years of age or older from June 2018 to October 2019 who received AA or 4F-PCC for the reversal of apixaban or rivaroxaban in the setting of ICH. Patients were excluded if they had received 4F-PCC prior to AA after its addition to the institution wide formulary. Other exclusion criteria were history or presence of heparin-induced thrombocytopenia or disseminated intravascular coagulation, estimated hematoma volume of >60 mL, Glasgow Coma Scores <7, or no repeat CT head scan. Information was collected from the electronic medical records. The primary outcome was the achievement of excellent or good hemostatic efficacy upon the repeat computer tomography (CT) scan performed after the infusion of study drugs. Secondary outcomes included disposition, survival to hospital discharge, 30-day readmission, length of hospital stay, length of ICU stay, incidence of thromboembolic events.

RESULTS

A total of 24 patients were included in the study, of which 9 received AA and 15 received 4F-PCC. The achievement of excellent or good hemostatic efficacy upon repeat CT scan occurred in 7 (77.8%) patients in the AA group and in 14 (93.3%) patients in the 4-F PCC group. All patients in the AA group survived to hospital discharge with no 30-day morality and 86.7% patients in the 4F-PCC group.

CONCLUSION

This study suggests that real-world clinical and safety outcomes between andexanet alfa and 4F-PCC for the reversal of factor Xa inhibitors in the setting of ICH are similar to ones reported in clinical trials.

Direct Oral Anticoagulant Reversal in the Pediatric Emergency Department

ABSTRACT

Direct oral anticoagulants have been used in the adult population for years and are being used more frequently in pediatrics. Direct oral anticoagulants are chosen preferentially because they do not require close outpatient monitoring, have an equal or better safety profile, and are easy for patients to take. Warfarin is the previous, more commonly used oral anticoagulant and acts as a vitamin K antagonist. Direct oral anticoagulants mechanism of action is different in that they directly inhibit part of the coagulation cascade accomplishing the same end goal. Given their differing mechanisms, they require alternate medications for proper reversal when concerned about overdose of life-threatening bleeds. This review will outline the most commonly used direct oral anticoagulants in pediatric populations and the supporting (mainly adult) data available for proper reversal of these medications in times of need.

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.

Impact of Factor Xa Inhibitor Reversal with Prothrombin Complex Concentrate in Patients with Traumatic Brain Injuries

BACKGROUND

Anticoagulant use prior to trauma has been associated with increased incidence of traumatic brain injury (TBI), intracranial hemorrhage (ICH) progression, and mortality. Prothrombin complex concentrates (PCCs) are commonly used as off-label treatments for factor Xa inhibitor-associated life-threatening hemorrhage. At this time, there is no consensus regarding appropriate indication, target dose, or outcomes of PCC administration in patients presenting with traumatic ICH. This study seeks to evaluate the impact of reversal with PCC on hemorrhage progression and outcomes in patients with TBI on preinjury factor Xa inhibitors.

METHODS

This single-center retrospective cohort study included patients ≥ 18 years presenting with an acute TBI of any severity on apixaban or rivaroxaban from September 1, 2016, to September 1, 2019. Patients were grouped on the basis of receipt of PCCs for reversal (i.e., reversal or no reversal). Exclusion criteria included spontaneous ICH or known coagulopathy. Propensity score matching was conducted with the following variables: age, Abbreviated Injury Scale (head) score, and Charlson Comorbidity Index score. The primary outcome was hemorrhage stability within 48 h. Secondary outcomes included degree of hemorrhage progression, in-hospital mortality, discharge disposition, and incidence of thromboembolic events.

RESULTS

Of the 115 patients meeting inclusion criteria, 84 were included in the propensity score matched data set. Baseline characteristics, comorbidities, and TBI severity were similar. The majority of patients in the reversal group (35 [83.3%]) and the no reversal (NR) group (40 [95.2%]) experienced a mild TBI (admission Glasgow Coma Scale score of 14 to 15). In the reversal group, patients received 34.3 units/kg activated PCC, 30.5 units/kg four-factor PCC, or 54.9 units/kg four-factor PCC and activated PCC on average. There was no difference observed in the incidence of hemorrhage progression (10.8% NR vs. 15.0% reversal; p = 0.739) or in median change in ICH volume (0 mL NR vs. 1 mL reversal; p = 0.2199) between groups. Additionally, reversal did not affect in-hospital mortality (3 [7.1%] NR vs. 4 [9.5%] reversal; p > 0.999). One patient in the reversal group developed a deep vein thrombosis (DVT) during the hospitalization; however, this did not result in a statistically significant difference in the occurrence of DVT (p > 0.999).

CONCLUSIONS

This study demonstrated that PCC used for the treatment of factor Xa inhibitor-associated ICH related to mild TBI did not significantly impact the incidence or degree of hemorrhage progression, and PCC treatment did not result in increased thromboembolic events.

Cerebral Hemorrhage: Pathophysiology, Treatment, and Future Directions

Intracerebral hemorrhage (ICH) is a devastating form of stroke with high morbidity and mortality. This review article focuses on the epidemiology, cause, mechanisms of injury, current treatment strategies, and future research directions of ICH. Incidence of hemorrhagic stroke has increased worldwide over the past 40 years, with shifts in the cause over time as hypertension management has improved and anticoagulant use has increased. Preclinical and clinical trials have elucidated the underlying ICH cause and mechanisms of injury from ICH including the complex interaction between edema, inflammation, iron-induced injury, and oxidative stress. Several trials have investigated optimal medical and surgical management of ICH without clear improvement in survival and functional outcomes. Ongoing research into novel approaches for ICH management provide hope for reducing the devastating effect of this disease in the future. Areas of promise in ICH therapy include prognostic biomarkers and primary prevention based on disease pathobiology, ultra-early hemostatic therapy, minimally invasive surgery, and perihematomal protection against inflammatory brain injury.

Use of Prothrombin Complex Concentrate in Oral Anticoagulant-Associated Major Bleeding

Severe bleeding remains the most significant adverse effect associated with both warfarin and the direct oral anticoagulant agents. Due to the life-threatening nature of these bleeds, knowledge and understanding of agents that are able to rapidly overcome the anticoagulation effects of these medications is paramount to their use. Worldwide, the most commonly used agent for this indication is prothrombin complex concentrate (PCC). This review summarizes the evidence on the use of PCC in this population and provides practical information regarding patient-specific administration considerations.

CM-352 EFFICACY IN A MOUSE MODEL OF ANTICOAGULANT-ASSOCIATED INTRACRANIAL HAEMORRHAGE

BACKGROUND

Intracranial haemorrhage (ICH) is one of the major devastating complications of anticoagulation. Matrix metalloproteinases (MMPs) inhibition has been proposed as a novel pharmacological approach for ICH treatment.

OBJECTIVES

We evaluated the effects of CM-352 (MMPs-fibrinolysis inhibitor) in an experimental ICH model associated with oral anticoagulants as compared with clinically used prothrombin concentrate complex (PCC).

METHODS

ICH was induced by collagenase injection into the striatum of WT (C57BL/6J) anticoagulated mice (warfarin or rivaroxaban) and Mmp10 -/- mice. Hematoma volume and neurological deficits were measured 24h later by diaminobenzidine staining and different behavioural test. Circulating plasminogen activator inhibitor-1 (PAI-1) activity and interleukin-6 (IL-6) were measured in plasma samples and local inflammation was assessed by neutrophil infiltration. Finally, fibrinolytic effects of MMP-10 and rivaroxaban were evaluated by thromboelastometry and thrombin-activatable fibrinolysis inhibitor (TAFI) activation assays.

RESULTS

Only PCC reduced haemorrhage volume and improved functional outcome in warfarin-ICH, but both, PCC and CM-352 treatments, diminished haemorrhage volume (46%, p<0.01 and 64%, p<0.001, respectively) and ameliorated functional outcome in rivaroxaban-ICH. We further demonstrated that CM-352, but not PCC decreased neutrophil infiltration in the haemorrhage area at 24h. The effect of CM-352 could be related to MMP-10 inhibition since Mmp10-/- mice showed lower haemorrhage volume, better neurological score, reduced IL-6 levels and neutrophil infiltration, and increased PAI-1 after experimental ICH. Finally, we found that CM-352 reduced MMP-10 and rivaroxaban-related fibrinolytic effects in thromboelastometry and TAFI activation.

CONCLUSIONS

CM-352 treatment, by diminishing MMPs and rivaroxaban-associated fibrinolytic effects, might be a novel antihaemorrhagic strategy for rivaroxaban-associated ICH.

VSIG4 Attenuates NLRP3 and Ameliorates Neuroinflammation via JAK2-STAT3-A20 Pathway after Intracerebral Hemorrhage in Mice

Intracerebral hemorrhage (ICH) is a fatal cerebrovascular disease. Neuroinflammation plays an important pathological role in brain injury after ICH. NLRP3 contributes to the pathogenesis of ICH, but the underlying mechanisms regulating of NLRP3 remain elusive. V-set and immunoglobulin domain containing 4 (VSIG4), specifically expressed in resting tissue-resident macrophages, can deliver anti-inflammatory signals into various inflammatory diseases. However, the interaction between VSIG4 and NLRP3, as well as the underlying mechanisms after ICH have not been reported. C57BL/6 mice were subjected to the autologous blood injection ICH model. VSIG4 and NLRP3 levels of macrophages were detected following ICH. Ad-VSIG4 or controls were administered via intracerebroventricular (i.c.v) injection before ICH induction. STAT3 inhibitor (S31-201), JAK2 inhibitor (TG101348), or Ad-A20 RNAi was administered to investigate the role of JAK2-STAT3-A20 pathway in VSIG4-mediated neuroinflammation after ICH. Pro-inflammatory cytokine production, BBB disruption, brain water content, and neurological test were examined in ICH mice. VSIG4 levels were significantly decreased, and NLRP3 levels were significantly increased in the perihematomal brain tissues after ICH. Ad-VSIG4 attenuated NLRP3 levels and inhibited inflammation, as well as improved neurological function and reduced BBB disruption and brain water content. Furthermore, Ad-VSIG4 increased the protein levels of phosphorylated JAK2 and STAT3, and A20 levels at 24 h after ICH. STAT3 inhibitor, JAK2 inhibitor, and A20 RNAi abolished the beneficial effects of Ad-VSIG4 after ICH. In summary, these data suggested that VSIG4 attenuated NLRP3 and ameliorated neuroinflammation via JAK2-STAT3-A20 pathway after intracerebral hemorrhage in mice. VSIG4 might be an ideal therapeutic target for ICH patients.

Cost-effectiveness of andexanet alfa versus four-factor prothrombin complex concentrate for the treatment of oral factor Xa inhibitor-related intracranial hemorrhage in the US

AIM

To conduct a cost-effectiveness analysis (CEA) on the use of andexanet alfa for the treatment of factor Xa inhibitor-related intracranial hemorrhage (ICH) from the US third-party payer and societal perspectives.

METHODS

CEA compared andexanet alfa to prothrombin complex concentrate for the treatment of patients receiving factor Xa inhibitors admitted to hospital inpatient care with an ICH. The model comprised two linked phases. Phase 1 utilized a decision tree to model the acute treatment phase (admission of a patient with ICH into intensive care for the first 30 days). Phase 2 modeled long-term costs and outcomes using three linked Markov models comprising the six health states defined by the modified Rankin score.

RESULTS

The analysis showed that the strategy of using andexanet alfa for the treatment of factor Xa inhibitor-related ICH is cost-effective, with incremental cost-effectiveness per quality-adjusted life-year gained of $35,872 from a third-party payer perspective and $40,997 from a societal perspective over 20 years.

LIMITATIONS

(1) Absence of head-to-head trials comparing therapies included in the economic model, (2) lack of comparative long-term data on treatment efficacy, and (3) bias resulting from the study designs of published literature.

CONCLUSION

Given these results, the use of andexanet alfa for the reversal of anticoagulation in patients with factor Xa inhibitor-related ICH may improve quality of life and is likely to be cost-effective in a US context.

Eastern Association for the Surgery of Trauma Multicenter Trial: Comparison of pre-injury antithrombotic use and reversal strategies among severe traumatic brain injury patients

BACKGROUND

Trauma teams are often faced with patients on antithrombotic (AT) drugs, which is challenging when bleeding occurs. We sought to compare the effects of different AT medications on head injury severity and hypothesized that AT reversal would not improve mortality in severe traumatic brain injury (TBI) patients.

METHODS

An Eastern Association for the Surgery of Trauma-sponsored prospective, multicentered, observational study of 15 trauma centers was performed. Patient demographics, injury burden, comorbidities, AT agents, and reversal attempts were collected. Outcomes of interest were head injury severity and in-hospital mortality.

RESULTS

Analysis was performed on 2,793 patients. The majority of patients were on aspirin (acetylsalicylic acid [ASA], 46.1%). Patients on a platelet chemoreceptor blocker (P2Y12) had the highest mean Injury Severity Score (9.1 ± 8.1). Patients taking P2Y12 inhibitors ± ASA, and ASA-warfarin had the highest head Abbreviated Injury Scale (AIS) mean (1.2 ± 1.6). On risk-adjusted analysis, warfarin-ASA was associated with a higher head AIS (odds ratio [OR], 2.43; 95% confidence interval [CI], 1.34-4.42) after controlling for Injury Severity Score, Charlson Comorbidity Index, initial Glasgow Coma Scale score, and initial systolic blood pressure. Among patients with severe TBI (head AIS score, ≥3) on antiplatelet therapy, reversal with desmopressin (DDAVP) and/or platelet transfusion did not improve survival (82.9% reversal vs. 90.4% none, p = 0.30). In severe TBI patients taking Xa inhibitors who received prothrombin complex concentrate, survival was not improved (84.6% reversal vs. 84.6% none, p = 0.68). With risk adjustment as described previously, mortality was not improved with reversal attempts (antiplatelet agents: OR 0.83; 85% CI, 0.12-5.9 [p = 0.85]; Xa inhibitors: OR, 0.76; 95% CI, 0.12-4.64; p = 0.77).

CONCLUSION

Reversal attempts appear to confer no mortality benefit in severe TBI patients on antiplatelet agents or Xa inhibitors. Combination therapy was associated with severity of head injury among patients taking preinjury AT therapy, with ASA-warfarin possessing the greatest risk.

LEVEL OF EVIDENCE

Prognostic, level II.

Comparison of 4-factor PCC reversal of apixaban and rivaroxaban versus warfarin for intracranial hemorrhage

The purpose of this study is to assess efficacy of 4-factor prothrombin complex concentrates (4F-PCC) for direct oral anticoagulant (DOAC)-associated intracranial hemorrhage (ICH) as compared to its use in warfarin-associated ICH. A retrospective cohort study was performed to compare the efficacy of 4F-PCC for reversal of apixaban and rivaroxaban versus warfarin for ICH at Cooper University Health Care from January 2015 to December 2019. Patients included were ≥ 18 years of age who developed an ICH while on apixaban, rivaroxaban, or warfarin. The primary outcome was to compare the percentage of patients with Excellent or Good hemostatic efficacy after 4F-PCC administration. Secondary outcomes were to describe functional outcomes at discharge, in-hospital mortality, and thrombotic complications after 4F-PCC administration. A total of 159 patients were included; 115 patients received warfarin and 44 patients received a DOAC (apixaban, n = 22; rivaroxaban, n = 22). 70 patients were evaluable for the primary endpoint. Thirty-four (66.7%) patients in the warfarin group versus 14 (73.7%) patients in the DOAC group were determined to have excellent or good hemostatic efficacy (p = 0.57). In-hospital mortality (30.4% vs. 40.9%, p = 0.21) and thrombotic complications (9.6% vs. 11.4%, p = 0.67) were comparable between the warfarin vs. DOAC groups, respectively. This small, retrospective study found no difference in patients with excellent/good hemostatic efficacy after reversal with 4F-PCC for DOAC-associated ICH compared to warfarin-associated ICH. This study is limited by its retrospective nature and sample size. Larger, prospective studies are needed to further determine the efficacy of 4F-PCC in reversing DOAC-associated ICH.

Modeling the Clinical Implications of Andexanet Alfa in Factor Xa Inhibitor-Associated Intracerebral Hemorrhage

BACKGROUND AND OBJECTIVES

Andexanet alfa was recently approved as a reversal agent for the factor Xa inhibitors (FXais) apixaban and rivaroxaban, but its impact on long-term outcomes in FXai-associated intracerebral hemorrhage (ICH) is unknown. We aimed to explore potential clinical implications of andexanet alfa in FXai-associated ICH in this simulation study.

METHODS

We simulated potential downstream implications of andexanet alfa across a range of possible hemostatic effects using data from a single center that treats FXai-associated ICH with prothrombin complex concentrate (PCC). We determined baseline probabilities of inadequate hemostasis across patients taking FXai and those not taking FXai via multivariable regression models and then determined the probabilities of unfavorable 3-month outcome (modified Rankin Scale score 4-6) using models comprising established predictors and each patient's calculated probability of inadequate hemostasis. We applied bootstrapping with model parameters from this derivation cohort to simulate a range of hemostatic improvements and corresponding outcomes and then calculated absolute risk reduction (relative to PCC) and projected number needed to treat (NNT) to prevent 1 unfavorable outcome.

RESULTS

Training models using real-world patients (n = 603 total, 55 on FXai) had good accuracy in predicting inadequate hemostasis (area under the curve [AUC] 0.78) and unfavorable outcome (AUC 0.78). Inadequate hemostasis was strongly associated with unfavorable outcome (odds ratio 4.5, 95% confidence interval [CI] 2.0-9.9) and occurred in 11.4% of patients taking FXai. Across simulated patients taking FXai comparable to those in A Study in Participants With Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors (ANNEXA-4) study, predicted absolute risk reduction of unfavorable outcome was 4.9% (95% CI 1.3%-7.8%) when the probability of inadequate hemostasis was reduced by 33% and 7.4% (95% CI 2.0%-11.9%) at 50% reduction, translating to projected NNT of 21 (cumulative cost $519,750) and 14 ($346,500), respectively.

DISCUSSION

Even optimistic simulated hemostatic effects suggest that the costs and potential benefits of andexanet alfa should be carefully considered. Placebo-controlled randomized trials are needed before its use can definitively be recommended.

Hematoma Expansion and Clinical Outcomes in Patients With Factor-Xa Inhibitor-Related Atraumatic Intracerebral Hemorrhage Treated Within the ANNEXA-4 Trial Versus Real-World Usual Care

BACKGROUND AND PURPOSE

It is unestablished whether andexanet alfa, compared with guideline-based usual care including prothrombin complex concentrates, is associated with reduced hematoma expansion (HE) and mortality in patients with factor-Xa inhibitor-related intracerebral hemorrhage (ICH). We compared the occurrence of HE and clinical outcomes in patients treated either with andexanet alfa or with usual care during the acute phase of factor-Xa inhibitor-related ICH.

METHODS

Data were extracted from the multicenter, prospective, single-arm ANNEXA-4 trial (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of Factor Xa Inhibitors) and a multicenter observational cohort study, RETRACE-II (German-Wide Multicenter Analysis of Oral Anticoagulant-Associated Intracerebral Hemorrhage - Part Two). HE was based on computed tomography scans performed within 36 hours from baseline imaging. Inverse probability of treatment weighting was performed to adjust for baseline comorbidities and ICH severity. Patients presenting with atraumatic ICH while receiving apixaban or rivaroxaban within 18 hours of admission were included. Patients with secondary ICH or not fulfilling the inclusion criteria for the ANNEXA-4 trial were excluded. We compared ANNEXA-4 patients, who received andexanet alfa for hemostatic treatment, with RETRACE-II patients who were treated with usual care, primarily administration of prothrombin complex concentrates. Primary outcome was rate of HE defined as relative increase of ≥35%. Secondary outcomes comprised mean absolute change in hematoma volume, as well as in-hospital mortality and functional outcome.

RESULTS

Overall, 182 patients with factor-Xa inhibitor-related ICH (85 receiving andexanet alfa versus 97 receiving usual care) were selected for analysis. There were no relevant differences regarding demographic or clinical characteristics between both groups. HE occurred in 11 of 80 (14%) andexanet alfa patients compared with 21 of 67 (36%) usual care patients (adjusted relative risk, 0.40 [95% CI, 0.20-0.78]; P=0.005), with a reduction in mean overall hematoma volume change of 7 mL. There were no statistically significant differences among in-hospital mortality or functional outcomes. Sensitivity analysis including only usual care patients receiving prothrombin complex concentrates demonstrated consistent results.

CONCLUSIONS

As compared with usual care, andexanet alfa was associated with a lower rate of HE in atraumatic factor-Xa inhibitor-related ICH, however, without translating into significantly improved clinical outcomes. A comparative trial is needed to confirm the benefit on limiting HE and to explore clinical outcomes across patient subgroups and by time to treatment.

Roles of Four-Factor Prothrombin Complex Concentrate in the Management of Critical Bleeding

Four-factor prothrombin complex concentrate (4F-PCC) is the term used to describe a pathogen-reduced, lyophilized concentrate that contains therapeutic amounts of at least 4 coagulation factors: Factor II (FII), Factor VII (FVII), Factor IX (FIX), and Factor X (FX). 4F-PCC has proven to be an effective hemostatic agent compared to plasma transfusion in several prospective randomized trials in acute warfarin reversal. In recent years, 4F-PCC has been used in various acquired coagulopathies including post-cardiopulmonary bypass bleeding, trauma-induced coagulopathy, coagulopathy in liver failure, and major bleeding due to anti-FXa (anti-Xa) inhibitors (eg, rivaroxaban and apixaban). As transfusion of frozen plasma (FP) has not been found efficacious in the above critical bleeding scenarios, there is increasing interest in expanding the use of 4F-PCC. However, efficacy, safety, and clinical implications of expanded use of 4F-PCC have not been fully elucidated. Prothrombin time and international normalized ratio are commonly used to assess dose effects of 4F-PCC. Prothrombin time/international normalized ratio are standardly use for warfarin titration, but they are not suited for real-time monitoring of complex coagulopathies. Optimal dosing of 4F-PCC outside of the current approved use for vitamin K antagonist reversal is yet to be determined. In this review, we will discuss the use of 4F-PCC in four critical bleeding settings: cardiac surgery, major trauma, end-stage liver disease, and oral anti-Xa reversal. We will discuss recent studies in each area to explore the dosing, efficacy, and safety of 4F-PCC.

Retrospective Comparison of Andexanet Alfa and 4-Factor Prothrombin Complex for Reversal of Factor Xa-Inhibitor Related Bleeding

The aim of this retrospective study was to compare andexanet alfa and 4-factor prothrombin complex (4F-PCC) for reversal of factor Xa (FXa)-inhibitor bleeding. Patients that received andexanet alfa for reversal were included. An equivalent number of patients administered 4F-PCC for FXa-inhibitor bleeding were randomly selected as historical controls. The primary outcome was effective hemostasis achievement within 12 h, defined using ANNEXA-4 criteria. Thromboembolic events and mortality within 30 days were also evaluated. A total of 32 patients were included. Baseline characteristics were not statistically different between andexanet alfa (n = 16) and 4F-PCC (n = 16). Intracranial bleeding was the primary reversal indication in 43.8% versus 62.5% of patients, respectively. Effective hemostasis was reached in 75.0% of andexanet alfa patients compared to 62.5% of 4F-PCC patients (P = .70). Thromboembolic events occurred in 4 (25.0%) patients and 3 (18.8%) patients, respectively (P = .99). Mortality incidence was 12.5% and 31.3%, respectively (P = .39). Andexanet alfa and 4F-PCC attained hemostasis in a majority of patients. A high, but a similar rate of thromboembolic events was seen with both treatments. Prospective studies are needed to elucidate comparative risks and benefits of the 2 agents.

A Retrospective Review of Four-Factor Prothrombin Complex Concentrate for Factor Xa Inhibitor-Related Bleedings

BACKGROUND

The use of factor Xa inhibitors has grown in popularity; however, the risk of major bleeding events requires for the appropriate reversal agent. The recent approved agent for factor Xa inhibitor reversal, andexanet alfa, has limited clinical efficacy and safety data, and it can be a financial burden on healthcare systems due to its high cost. Four-factor prothrombin complex concentrate (4F-PCC) has been utilized off label in patients with factor Xa inhibitor-related bleedings. Objective: The aim of this study was to assess the safety and efficacy of 4F-PCC in managing factor Xa inhibitor-related bleedings.

METHODS

This is an observational, retrospective review of 4F-PCC usage in treating factor Xa inhibitor-related bleeds from May 2014 to December 2018 at a single health system. Efficacy was evaluated using the assessment criteria described by Sarode et al. Secondary outcomes analyzed included thromboembolic events, length of stay, mortality, and discharge disposition.

RESULTS

Fifty-nine patient charts were reviewed, and 48 patients were included in the study analysis. The administration of 4F-PCC achieved effective hemostasis in 33 patients (68%), and effective hemostasis was achieved in 12 patients (86%) who had intracranial hemorrhage and did not receive any surgical intervention. Thromboembolic events occurred in 4 patients within 30 days from 4F-PCC use. A majority of patients (85.4%) were discharged from the hospital to home or long-term care; 7 patients (14.6%) expired in the hospital.

CONCLUSION

Efficacy was achieved in over half of the patient population in this cohort who received 4F-PCC for factor Xa inhibitor-related bleeding events.

Indirect antiplatelet effects of rivaroxaban in a patient with intracranial hemorrhage: An underappreciated coagulopathy of factor Xa inhibitors?

Rivaroxaban is a direct oral anticoagulant (DOAC) used for prophylaxis and treatment of many prothrombotic states. The anticoagulation effects of rivaroxaban are produced by selectively binding and inhibiting factor Xa, causing delayed thrombin generation. Additionally, the delay in thrombin generation produces an indirect, dose dependent antiplatelet effect via reduction in tissue factor platelet aggregation. As with any anticoagulant, rivaroxaban use increases a patient's risk for major and minor hemorrhagic events. With mortality rates reported as high as 25% for those who experience an intracranial hemorrhage (ICH), immediate mitigation of hematoma and hemorrhage volume expansion is imperative. Management strategies include utilizing prothrombin complex concentrates (PCC) and factor Xa inhibitor specific antidotes, such as coagulation factor Xa recombinant, inactivated-zhzo. Routine monitoring or management of DOAC induced antiplatelet effects is ill-defined and not a part of routine standard of care. We report the first case, to our knowledge, of rivaroxaban's indirect antiplatelet effects identified by platelet function assays and managed with four-factor PCC and desmopressin in a patient experiencing an ICH. Further exploration is needed to determine the true clinical impact attributed to rivaroxaban's antiplatelet effects.

Andexanet alfa and four-factor prothrombin complex concentrate for reversal of apixaban and rivaroxaban in patients diagnosed with intracranial hemorrhage

Limited data exists regarding the clinical outcomes of andexanet alfa and four factor prothrombin complex concentrate (4F-PCC) for reversal of apixaban or rivaroxaban in the setting of intracranial hemorrhage (ICH). The objective of this study was to evaluate clinical outcomes of 4F-PCC and andexanet alfa for reversal of ICH associated with oral factor Xa inhibitors. This was a retrospective, single-center, case series evaluating hemostatic efficacy of patients receiving andexanet alfa) or 4F-PCC for reversal of apixaban or rivaroxaban after ICH. Secondary endpoints included in-hospital mortality, thrombotic complications, timing of reversal agents, intensive care unit and hospital length of stay, patient disposition, and 30-day readmission rate. During the study period, 21 patients received andexanet alfa and 35 received 4F-PCC. Hemostatic efficacy occurred in 64.7% of patients receiving andexanet alfa and 54.8% of receiving 4F-PCC. Thirty-day all-cause mortality was 45.2% for 4F-PCC and 30% for andexanet alfa. Thrombotic events were higher with 4F-PCC (31.4%) compared to andexanet alfa (14.3%). Median time from presentation to administration of reversal agent was 2.67 [1.75-4.13] hours with andexanet alfa and 1.73 [1.21-3.55] hours with 4F-PCC. Discharge to skilled nursing facilities and 30-day readmission were similar between groups. In this cohort, reversal with andexanet alfa and 4F-PCC differed in terms ofhemostatic efficacy and thrombotic events after ICH in patients anticoagulated with apixaban or rivaroxaban.

Impact of a pharmacist driven anticoagulation reversal program at a large academic medical center

In major/life-threatening bleeding, administration of timely and appropriate reversal agents is imperative to reduce morbidity and mortality. Due to complexities associated with the use of reversal agents, a clinical pharmacist-driven anticoagulation reversal program (ARP) was developed. The goal of this program was to ensure appropriateness of reversal agents based on the clinical scenario, optimize selection and avoid unintended consequences. This study describes the impact of a pharmacist-driven anticoagulation program on patient outcomes and cost. A single center retrospective chart review of adult patients whom the ARP was consulted from October 2018 to January 2020 was performed. Patients were included in the efficacy analysis if they were > 18 years of age and presented with acute bleeding. Patients were excluded from the efficacy analysis if the recommended reversal agent was not administered, if a repeat head CT was not available for patients who presented with intracranial hemorrhage (ICH), or if the patient was not bleeding. All patients were included in the economic evaluation. The primary outcome was the percentage of patients who achieved effective hemostasis within 24 h of anticoagulation reversal. Secondary outcomes include incidence of thromboembolic events, in-hospital mortality, and cost avoidance. One hundred twenty-one patients were evaluated by the ARP with 92 patients included in the efficacy analysis. The primary sites of bleeding were ICH in 46% and gastrointestinal (GI) in 29%. Hemostasis was achieved in 84% of patients. Thrombotic events occurred in 7.4% of patients and in-hospital mortality was 26.4%. Total cost avoidance was $1,005,871.78. To our knowledge, this is the first study to evaluate the impact of a pharmacist-driven ARP on clinical and economic outcomes. Implementation of a pharmacist-driven ARP was associated with favorable outcomes and cost savings.

Hemostatic Efficacy and Anti-FXa (Factor Xa) Reversal With Andexanet Alfa in Intracranial Hemorrhage: ANNEXA-4 Substudy

Background and Purpose

Andexanet alfa is a recombinant modified human FXa (factor Xa) developed to reverse FXa inhibition from anticoagulants. Hemostatic efficacy and reversal of anti-FXa activity with andexanet were assessed in patients from the ANNEXA-4 study (Andexanet Alfa, a Novel Antidote to the Anticoagulation Effects of FXa Inhibitors) with intracranial hemorrhage (ICrH).

Methods

ANNEXA-4 was a single-arm study evaluating andexanet in patients presenting with major bleeding ≤18 hours after taking an FXa inhibitor. Patients received a bolus plus 2-hour infusion of andexanet. Brain imaging in patients with ICrH was performed at baseline and at 1 and 12 hours postandexanet infusion. Coprimary efficacy outcomes were change in anti-FXa activity and hemostatic efficacy at 12 hours (excellent/good efficacy defined as ≤35% increase in hemorrhage volume/thickness). Safety outcomes included occurrence of thrombotic events and death at 30 days.

Results

A total of 227 patients with ICrH were included in the safety population (51.5% male; mean age 79.3 years) and 171 in the efficacy population (99 spontaneous and 72 traumatic bleeds). In efficacy evaluable patients, excellent/good hemostasis 12 hours postandexanet occurred in 77 out of 98 (78.6%) and in 58 out of 70 (82.9%) patients with spontaneous and traumatic bleeding, respectively. In the subanalysis by FXa inhibitor treatment group in the efficacy population, median of percent change in anti-FXa from baseline to nadir showed a decrease of 93.8% for apixaban-treated patients (n=99) and by 92.6% for rivaroxaban-treated patients (n=59). Within 30 days, death occurred in 34 out of 227 (15.0%) patients and thrombotic events occurred in 21 out of 227 (9.3%) patients (safety population).

Conclusions

Andexanet reduced anti-FXa activity in FXa inhibitor-treated patients with ICrH, with a high rate of hemostatic efficacy. Andexanet may substantially benefit patients with ICrH, the most serious complication of anticoagulation.

Registration

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02329327.

Meta-Analysis of Reversal Agents for Severe Bleeding Associated With Direct Oral Anticoagulants

BACKGROUND

Direct oral anticoagulants (DOACs) have shown a positive benefit-risk balance in both clinical trials and real-world data, but approximately 2% to 3.5% of patients experience major bleeding annually. Many of these patients require hospitalization, and the administration of reversal agents may be required to control bleeding.

OBJECTIVES

The aim of this study was to investigate clinical outcomes associated with the use of 4-factor prothrombin complex concentrates, idarucizumab, or andexanet for reversal of severe DOAC-associated bleeding.

METHODS

The investigators systematically searched for studies of reversal agents for the treatment of severe bleeding associated with DOAC. Mortality rates, thromboembolic events, and hemostatic efficacy were meta-analyzed using a random effects model.

RESULTS

The investigators evaluated 60 studies in 4,735 patients with severe DOAC-related bleeding who were treated with 4-factor prothrombin complex concentrates (n = 2,688), idarucizumab (n = 1,111), or andexanet (n = 936). The mortality rate was 17.7% (95% confidence interval [CI]: 15.1% to 20.4%), and it was higher in patients with intracranial bleedings (20.2%) than in patients with extracranial hemorrhages (15.4%). The thromboembolism rate was 4.6% (95% CI: 3.3% to 6.0%), being particularly high with andexanet (10.7%; 95% CI: 6.5% to 15.7%). The effective hemostasis rate was 78.5% (95% CI: 75.1% to 81.8%) and was similar regardless of the reversal agent considered. The rebleeding rate was 13.2% (95% CI: 5.5% to 23.1%) and 78% of rebleeds occurred after resumption of anticoagulation. The risk of death was markedly and significantly associated with failure to achieve effective hemostasis (relative risk: 3.63; 95% CI: 2.56 to 5.16). The results were robust regardless of the type of study or the hemostatic scale used.

CONCLUSIONS

The risk of death after severe DOAC-related bleeding remains significant despite a high rate of effective hemostasis with reversal agents. Failure to achieve effective hemostasis strongly correlated with a fatal outcome. Thromboembolism rates are particularly high with andexanet. Comparative clinical trials are needed.

Review of Prothrombin Complex Concentrates Use in Apixaban and Rivaroxaban Associated Intracranial Hemorrhages

STUDY OBJECTIVE

Summarize the studies evaluating the use of 4-factor prothrombin complex concentrates in the management of apixaban and rivaroxaban associated intracranial hemorrhages.

METHODS

A PubMed literature search was conducted for articles published between 2013 and 2020 which contained the following terms in their title: (1) apixaban, rivaroxaban, or factor Xa inhibitor*, and (2) prothrombin complex concentrate*.

RESULTS

Eighteen observational studies were included. When a ∼25 units/kg (range: 25-26.9 units/kg) non-activated 4 factor prothrombin complex concentrate dose was administered, the hemostatic effectiveness rates were ≥ 79% in 2/4 studies that utilized the Sarode et al criteria, in comparison to 4/5 studies that administered a 50 units/kg dose. The mortality rates were < 20% in 7/9 studies with hemostatic effectiveness rates ≥ 79%. Mortality rates were lower in the studies demonstrating higher hemostatic effectiveness rates and including patients with higher Glasgow coma scale scores and lower intracerebral hemorrhage volumes. Overall, the thromboembolic event rates were 0-18%, with 16/18 studies demonstrating rates ≤ 10%. The thromboembolic event rates were not dose or agent dependent.

CONCLUSION

Rates of hemostatic effectiveness were influenced by the definition of hemostatic effectiveness, dose administered, and patient severity. Studies suggest that higher doses may result in higher hemostatic effectiveness rates without increasing the risk of experiencing a thromboembolic event. This review may be used by providers to modify or validate their reversal strategy approach until well designed studies are available.

A meta-analysis of andexanet alfa and prothrombin complex concentrate in the treatment of factor Xa inhibitor-related major bleeding

Background

Andexanet alfa (andexanet) and prothrombin complex concentrate (PCC) are both reversal agents for major bleeding in patients using factor Xa inhibitors (FXaIs). Our aim was to evaluate the current evidence for the effectiveness and safety of andexanet and PCC in a systematic review and meta-analysis.

Objectives

Primary objective was hemostatic effectiveness. Secondary objectives were thromboembolic event rate and mortality.

Methods

A systematic review was performed in PubMed and Embase. Studies describing the effectiveness and/or safety of PCC or andexanet in patients with major bleeding using FXaIs were included. Meta-analysis was performed using a random-effects model.

Results

Seventeen PCC studies, 3 andexanet studies, and 1 study describing PCC and andexanet were included, comprising 1428 PCC-treated and 396 andexanet-treated patients. None of the included studies had control groups, hampering a pooled meta-analysis to compare the two reversal agents. Separate analyses for andexanet and PCC were performed. In subgroup analysis, the pooled proportion of patients with effective hemostasis in studies that used Annexa-4 criteria demonstrated a hemostatic effectiveness of 0.85 (95% confidence interval [CI], 0.80-0.90) in PCC and 0.82 (95% CI, 0.78-0.87) in andexanet studies. The pooled proportion of patients with thromboembolic events was 0.03 (95% CI, 0.02-0.04) in PCC and 0.11 (95% CI, 0.04-0.18) in andexanet studies.

Conclusion

Based on the available evidence with low certainty from observational studies, PCC and andexanet demonstrated a similar, effective hemostasis in the treatment of major bleeding in patients using FXaIs. Compared to PCC, the thromboembolic event rate appeared higher in andexanet-treated patients.

Prothrombin complex concentrate in major bleeding associated with DOACs; an updated systematic review and meta-analysis

BACKGROUND

Four-factor prothrombin complex concentrate (PCC) is frequently used as a reversal agent for major bleeding in patients on factor Xa inhibitors. Piran et al. reviewed its safety and efficacy for the first time in 2018. However, more studies have been published on the matter since then. The aim of this study is to investigate the efficacy and safety of this use and update this review.

METHODS

We systematically searched in Medline, Scopus, and the Cochrane Library from 1/1/2018 to 6/19/2020. A random effects model meta-analysis of proportions was used to study the efficacy of PCC on major bleeding control, mortality and thrombosis incidence.

RESULTS

33 studies (n = 2568 patients), with the majority of studies being uncontrolled retrospective cohort studies, were included; atrial fibrillation was the main factor Xa inhibitors indication and approximately 62% of patients presented with intracranial hemorrhage. We estimated the pooled proportion outcomes for hemostasis (80%, CI 0.75-0.84), mortality (15%, CI 0.11-0.19) and thromboembolic adverse events (3%, CI 0.02-0.05). High versus low dose PCC did not affect hemostasis or thrombosis. Patients with ICH had higher mortality rates (22%, CI 0.13-0.32). Heterogeneity was significant (Ι² > 50% with p < 0.05) for all pooled proportional outcomes. The quality of evidence was low given that included studies were not randomized or controlled.

CONCLUSION

Our study demonstrates the efficacy and safety of the off label use of 4F PCC in major bleeding associated with factor Xa inhibitors. Our data require further validation with future randomized clinical trials.

Low-dose versus standard-dose four-factor prothrombin complex concentrate for factor-Xa inhibitor reversal in spontaneous and traumatic intracranial hemorrhage

STUDY OBJECTIVES

Current neurocritical care guidelines recommend 50 IU/kg four-factor prothrombin complex concentrate (4PCC) for factor Xa inhibitor (FXaI) reversal in intracranial hemorrhage (ICH) based on few clinical studies conducted among non-ICH subjects. Two recent studies suggest that low-dose (25 IU/kg) 4PCC may be similar to 50 IU/kg in reversal of FXaI in ICH, and both 25 and 50 IU/kg doses are used in clinical practice for this indication. To our knowledge, no studies have directly compared 25 IU/kg versus 50 IU/kg 4PCC for FXaI reversal in ICH. The purpose of this study is to determine whether there is a difference in hemostatic efficacy between 25 IU/kg versus 50 IU/kg 4PCC for FXaI reversal in ICH.

DESIGN

This multicenter, retrospective cohort study was performed in five hospitals in central Texas from November 2013 to December 2019.

DATA SOURCE

Patients were identified with a medication use report of 4PCC and were classified in the low- or standard-dose group based on whether the 25 IU/kg or 50 IU/kg dose was received, respectively.

PATIENTS

A total of 93 patients were included (25 IU/kg, n = 62; 50 IU/kg, n = 31).

MEASUREMENTS AND MAIN RESULTS

There was no difference in hemostatic efficacy between groups (82.3% low dose vs. 83.9% standard dose, p = 0.846). No differences were identified in-hospital mortality, length of stay, thrombotic events, or the need for surgery or additional blood products between groups.

CONCLUSION

For the reversal of FXaI in ICH, a 25 IU/kg dose may be an effective alternative to 50 IU/kg 4PCC dosing.