betrixaban and Venous-Thromboembolism

Betrixaban and rivaroxaban are the direct anticoagulants approved in the United States for extended venous thromboembolism (VTE) prophylaxis among acutely ill medical patients. The efficacy and safety in specific subgroups remain unclear.. A meta-analysis of 3 randomized trials involving extended thromboprophylaxis with betrixaban or rivaroxaban versus enoxaparin for medically ill patients was performed to compare VTE (composite of asymptomatic proximal and symptomatic deep vein thrombosis, pulmonary embolism, or VTE-related death) and major bleeding in subgroups by baseline D-dimer, age, sex, and major medical illness on hospitalization. Risk difference (RD) was computed with the Mantel-Haenszel method by fitting a fixed-effect model. Heterogeneity of treatment effect across subgroups was examined using the nominal thresholds of P < 0.05 and I2 > 75%.. Compared with enoxaparin, extended betrixaban or rivaroxaban reduced VTE (RD = -1.51% [95% CI, -2.32% to -0.69%]; P = 0.0003) without excess major bleeding (RD = 0.12% [-0.05% to 0.29%]; P = 0.16). A significant effect modification was observed in the subgroups by D-dimer (P = 0.004) and age (P = 0.04). Patients with D-dimer >2× upper limit of normal (ULN) experienced a greater VTE reduction (RD = -2.39% [-3.57% to -1.21%]; P < 0.0001) than those with ≤2×ULN (RD = -0.26% [-1.08% to 0.56%]; P = 0.53). Similarly, patients aged ≥75 years had a greater VTE reduction (RD = -2.29% [-3.49% to -1.09%]; P = 0.0002) than those aged <75 years (RD = -0.63% [-1.70% to 0.44%]; P = 0.25). Treatment effect was consistent across the remaining subgroups.. A more favorable efficacy and comparable safety outcome associated with extended betrixaban or rivaroxaban were observed among medical inpatients with D-dimer >2×ULN or aged ≥75 years. D-dimer and advanced age may assist in decision-making on pharmacological thromboprophylaxis for hospitalized medical patients.

Topics: Anticoagulants; Benzamides; Humans; Pyridines; Risk Factors; Rivaroxaban; Venous Thromboembolism

Venous thromboembolism (VTE) is the leading preventable cause of death in hospitalized patients and data consistently show that acutely ill medical patients remain at increased risk for VTE-related morbidity and mortality in the post-hospital discharge period. Prescribing extended thromboprophylaxis for up to 45 days following an acute hospitalization in key patient subgroups that include more than one-quarter of hospitalized medically-ill patients represents a paradigm shift in the way hospital-based physicians think about VTE prevention. Advances in the field of primary thromboprophylaxis in acutely-ill medical patients using validated VTE and bleeding risk assessment models have established key patient subgroups at high risk of VTE and low risk of bleeding that may benefit from both in-hospital and extended thromboprophylaxis. The direct oral anticoagulants betrixaban and rivaroxaban are now U.S. Food and Drug Administration-approved for in-hospital and extended thromboprophylaxis in medically ill patients and provide net clinical benefit in these key subgroups. Coronavirus disease-2019 may predispose patients to VTE due to excessive inflammation, platelet activation, endothelial dysfunction, and hemostasis. The optimum preventive strategy for these patients requires further investigation. This article aims to review the latest concepts in predicting and preventing VTE and discuss the new era of extended thromboprophylaxis in hospitalized medically ill patients.

Topics: Anticoagulants; Benzamides; COVID-19; Critical Care; Decision Support Systems, Clinical; Duration of Therapy; Hospitalization; Humans; Medical Informatics; Patient Discharge; Pulmonary Embolism; Pyridines; Risk Assessment; Rivaroxaban; SARS-CoV-2; Venous Thromboembolism; Venous Thrombosis

Although venous thromboembolism prophylaxis of acute medically ill patients is commonly employed, a percentage of high-risk patients still have venous thromboembolic events within 30 days of discharge. Research over the last several years has attempted to identify characteristics of these high-risk patients to facilitate provision of extended prophylaxis and venous thromboembolic event reduction; however, extended prophylaxis has been associated with a significant increase in the risk for major bleeding until recently. Betrixaban, a new oral direct Xa inhibitor with once-daily dosing and limited renal elimination, significantly reduces the risk of venous thromboembolism without increasing the risk for major bleeding. Consequently, betrixaban is the only anticoagulant approved by the Food and Drug Administration for preventing venous thromboembolism with extended prophylaxis in acute medically ill patients.

Topics: Benzamides; Factor Xa Inhibitors; Hemorrhage; Hospitalization; Humans; Patient Discharge; Pyridines; Venous Thromboembolism

The risk of a venous thromboembolic event is not limited to the pre-hospital, hospital, or immediate post-hospital period. Because of challenges with data collection, the risk of venous thromboembolism (VTE) up to 3 months post-hospitalization for patients with acute and serious medical problems in the setting of chronic disease and/or risk factors for VTE is probably under reported. The growing acceptance and indications of direct oral anticoagulants (DOACs) now includes an indication for VTE prevention for one of the Factor Xa agents. In this paper, the authors explore the issue of VTE in the extended post-hospital period and strategies to provide protection from these morbid and potentially mortal events with oral anticoagulants.

Topics: Benzamides; Factor Xa Inhibitors; Hemorrhage; Hospitalization; Humans; Patient Discharge; Practice Guidelines as Topic; Pulmonary Embolism; Pyridines; Venous Thromboembolism; Venous Thrombosis

Non-vitamin K antagonist oral anticoagulants (NOACs) include dabigatran, which inhibits thrombin, and apixaban, betrixaban, edoxaban and rivaroxaban, which inhibit factor Xa. In large clinical trials comparing the NOACs with the vitamin K antagonist (VKA) warfarin, dabigatran, apixaban, rivaroxaban and edoxaban were at least as effective for stroke prevention in atrial fibrillation and for treatment of venous thromboembolism, but were associated with less intracranial bleeding. In addition, the NOACs are more convenient to administer than VKAs because they can be given in fixed doses without routine coagulation monitoring. Consequently, the NOACs are now replacing VKAs for these indications, and their use is increasing. Although, as a class, the NOACs have a favourable benefit-risk profile compared with VKAs, choosing among them is complicated because they have not been compared in head-to-head trials. Therefore, selection depends on the results of the individual trials, renal function, the potential for drug-drug interactions and preference for once- or twice-daily dosing. In addition, several 'special situations' were not adequately studied in the dedicated clinical trials. For these situations, knowledge of the unique pharmacological features of the various NOACs and judicious cross-trial comparison can help inform prescription choices. The purpose of this position article is therefore to help clinicians choose the right anticoagulant for the right patient at the right dose by reviewing a variety of special situations not widely studied in clinical trials.

Topics: Administration, Oral; Antibodies, Monoclonal, Humanized; Anticoagulants; Arginine; Atrial Fibrillation; Benzamides; Biomarkers; Blood Coagulation; Clinical Trials as Topic; Dabigatran; Drug Administration Schedule; Factor Xa; Heart Diseases; Humans; Piperazines; Pyrazoles; Pyridines; Pyridones; Recombinant Proteins; Risk; Rivaroxaban; Stroke; Thiazoles; Thrombin; Venous Thromboembolism; Vitamin K; Warfarin

Patients admitted with acute medical conditions are at prolonged risk for venous thrombosis. The efficacy and safety, and the appropriate duration of thromboprophylaxis have not been clearly determined. In recent years, direct coagulation factor inhibitors have been successfully tested for the prevention and treatment of arterial and venous thromboembolism. Betrixaban is a novel direct inhibitor of factor Xa with a noteworthy pharmacological feature: limited renal clearance. Areas covered: This review focuses on the pharmacological profile of Betrixaban, including its clinical efficacy and safety. It also covers the results of the pivotal APEX trial assessing the safety and efficacy of betrixaban for extended thromboprophylaxis in patients with acute medical conditions. Expert opinion: The role of extended thromboprophylaxis in acutely ill medical patients is subject to debate. The beneficial results in terms of VTE prevention were offset by the relevant increase in major bleeding. Betrixaban is the only direct oral anticoagulant to have shown a favorable risk-benefit profile in this setting especially in patients at higher risk for thrombosis.

Topics: Benzamides; Factor Xa Inhibitors; Humans; Pyridines; Venous Thromboembolism

Acutely ill hospitalized medical patients remain at high thromboembolic risk for several weeks after discharge. Previous trials with extended-duration thromboprophylaxis using enoxaparin, apixaban, and rivaroxaban failed to achieve acceptable net clinical benefit, largely due to excess of major bleeding. Betrixaban is a novel factor Xa inhibitor with unique pharmacokinetic properties, including low renal clearance, long half-life, and low peak-to-trough ratio. The phase III APEX trial (N = 7513) compared a betrixaban 160 mg loading dose followed by 80 mg once daily for 35-42 days, with enoxaparin 40 mg once daily for 6-14 days; the betrixaban dose was reduced for renal impairment or a concomitant strong P-glycoprotein (P-gp) inhibitor. The primary efficacy endpoint of composite thrombotic events was not different between treatment arms in cohort 1 (D-dimer ≥ 2 × upper limit of normal). Subsequent exploratory analyses showed a statistically significant difference favoring betrixaban for symptomatic venous thromboembolism and net clinical benefit in the overall population. For the primary safety outcome, betrixaban did not significantly increase major bleeding compared with enoxaparin. Based on available data from the APEX trial and subanalyses, the use of betrixaban in patients similar to those enrolled in the APEX trial can reduce the risk of thromboembolic events without increasing the risk of major bleeding. Patients who may benefit more from betrixaban therapy include those with elevated D-dimer, history of venous thromboembolism, hospitalized for ischemic stroke, hospitalized for heart failure with N-terminal pro-B-type natriuretic peptide ≥ 1975 ng/L, or two or more VTE risk factors. Reduced-dose betrixaban does not appear to provide the same clinical utility as full-dose betrixaban.

Topics: Anticoagulants; Benzamides; Drug Therapy, Combination; Enoxaparin; Factor Xa Inhibitors; Hemorrhage; Hospitalization; Humans; Pyridines; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Stroke; Treatment Outcome; Venous Thromboembolism

Cancer accounts for 20% of all venous thromboembolism (VTE) worldwide and cancer patients are at four- to sevenfold increased risk of thrombosis compared to non-cancer patients. VTE is also a morbid complication of cancer and its incidence is rising. Thrombosis is also a second leading cause of death in cancer patients. The standard of care management for the prevention and treatment of cancer-associated thrombosis (CAT) remains the administration of low-molecular-weight heparins (LMWHs). In the last decade, five direct oral anticoagulants (DOACs), dabigatran, rivaroxaban, apixaban, edoxaban and betrixaban, have been approved for the treatment and prevention of VTE in the general patient population. In this review, we discuss the results of the already published clinical trials with DOACs in the treatment of CAT and the ongoing clinical trials with DOACs in the prevention and treatment of CAT.

Topics: Administration, Oral; Anticoagulants; Benzamides; Dabigatran; Heparin, Low-Molecular-Weight; Humans; Neoplasms; Pyrazoles; Pyridines; Pyridones; Randomized Controlled Trials as Topic; Rivaroxaban; Thiazoles; Venous Thromboembolism

Topics: Acute Disease; Anticoagulants; Bayes Theorem; Benzamides; Delayed-Action Preparations; Factor Xa Inhibitors; Heparin; Heparin, Low-Molecular-Weight; Humans; Network Meta-Analysis; Patient Safety; Pyridines; Treatment Outcome; Venous Thromboembolism

Venous thromboembolism (VTE) is a significant healthcare burden with approximately 900,000 events annually in the United States, over half of which are healthcare-associated. This number is anticipated to double by 2050. Group prophylaxis strategies confined to the inpatient setting appear to have minimal impact on the reduction of post-discharge VTE in medically ill patients due to shortened lengths of stay and a heterogenous population that includes patients at low risk for VTE. In accordance with current guideline recommendations, very few (<5%) medically ill patients are discharged with extended prophylaxis, which potentially creates a clinical gap for at-risk patients as VTE risk has been shown to persist for up to 90 days. Initial studies of extended thromboprophylaxis in acutely ill medical patients with enoxaparin, rivaroxaban and apixaban showed little to no benefit towards VTE reduction that was consistently outweighed by increased bleeding. The more recent APEX study that compared betrixaban to enoxaparin in an enriched patient population at high-risk for VTE was the first study of extended thromboprophylaxis that showed similar efficacy in VTE prevention without an increase in major bleeding. Based on the APEX results, betrixaban recently gained FDA approval for extended thromboprophylaxis in acutely ill medical patients. Recognition that up to half of medically ill patients are not at sufficient risk to warrant thromboprophylaxis has driven extensive research towards development of scientifically derived and validated VTE risk assessment models intended to identify patients who do not warrant prophylaxis, as well as those at high risk who may derive benefit from extended thromboprophylaxis. This article will review prior and ongoing extended thromboprophylaxis studies, VTE and bleed risk assessment models, incorporation of biomarkers in VTE risk assessment and key issues in the paradigm shift towards individualized VTE prophylaxis in acutely ill medical patients.

Topics: Age Factors; Anticoagulants; Benzamides; Drug Administration Schedule; Enoxaparin; Hemorrhage; Hospitalization; Humans; Meta-Analysis as Topic; Mobility Limitation; Patient Discharge; Pyridines; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Rivaroxaban; Time Factors; Venous Thromboembolism

To review the pharmacology, pharmacokinetics, efficacy, and safety of the factor Xa (FXa) inhibitor betrixaban for extended-duration prophylaxis of acute medically ill patients with venous thromboembolism (VTE) risk factors.. A MEDLINE/PubMed (January 1990 to October 2017) search was conducted using the following keywords: betrixaban, PRT054021, FXa inhibitor, novel oral anticoagulant, NOAC, direct oral anticoagulant, DOAC, and target specific oral anticoagulant, TSOAC. References of identified articles were searched by hand for additional relevant citations.. We included English-language articles evaluating betrixaban pharmacology, pharmacokinetics, efficacy, or safety in human subjects for VTE prophylaxis.. Betrixaban is a FXa inhibitor that decreases prothrombinase activity and thrombin generation. Betrixaban efficacy and safety has been compared with that of enoxaparin for prophylaxis of VTE in acutely ill medical patients. In the APEX trial and substudies, extended-duration betrixaban was superior in efficacy to standard-duration enoxaparin in patients at high risk for VTE, including those with elevated D-dimer levels (≥2× upper limit of normal) and of older age (≥75 years). Betrixaban is noninferior to enoxaparin in rates of major bleeding, but the former is associated with more clinically relevant nonmajor bleeding events.. Betrixaban is the first oral agent approved for extended-duration VTE prophylaxis in acutely ill hospitalized patients. Extended-duration thromboprophylaxis with betrixaban reduces the risk of VTE compared with standard-duration thromboprophylaxis with enoxaparin but is associated with increased risk of bleeding.

Topics: Benzamides; Factor Xa Inhibitors; Humans; Pyridines; Randomized Controlled Trials as Topic; Treatment Outcome; Venous Thromboembolism

Prophylaxis for venous thromboembolism (VTE) in hospitalized acutely ill medical patients is a well-established practice. Despite the increased use of inpatient prophylaxis, the duration of hospitalization is typically shorter than the duration of VTE prophylaxis provided in clinical trials. In addition, VTE events after hospitalization are not unusual, with most events occurring within 30 days of hospital discharge. Therefore, the 30-day time period postdischarge has been identified as a stage in which patients are still at high risk of developing VTE. Attempts to provide extended prophylaxis with enoxaparin, rivaroxaban, or apixaban in patients with acute medical illness have been met with mixed results. Although some of these agents have reduced the incidence of VTE with extended prophylaxis, all of these agents have also demonstrated a significant increase in major bleeding that seems to offset any potential benefit. A recent trial of a new direct factor Xa inhibitor, betrixaban, demonstrated a reduction in VTE events with extended prophylaxis without significantly increasing the risk of major bleeding. Understanding appropriate patient selection, dosing, and outcomes associated with betrixaban will be important to potentially reducing the continued risk of VTE in patients with acute medical illness.

Topics: Acute Disease; Aged; Aged, 80 and over; Benzamides; Factor Xa Inhibitors; Female; Hospitalization; Humans; Male; Middle Aged; Pyridines; Venous Thromboembolism

The role of betrixaban in the prevention of venous thromboembolism (VTE) in acutely medically ill patients and its efficacy and safety profiles are reviewed.. Acutely medically ill patients have a high risk of developing VTE during hospitalization, and this risk continues into the postdischarge phase. Extended-duration betrixaban therapy has been evaluated in a large clinical trial (the APEX trial) and in a meta-analysis of pooled data on acutely medically ill patients. These studies have shown positive outcomes when betrixaban was compared with conventional-duration subcutaneous enoxaparin therapy for prevention of VTE in acutely medically ill patients. In parallel with these results, oral betrixaban therapy was found to be associated with a rate of major bleeding comparable to that associated with subcutaneous enoxaparin therapy; however, betrixaban use was associated with a higher cumulative rate of major and clinically relevant nonmajor bleeding. In the APEX trial, the primary endpoint was not met in 1 of the prespecified cohorts, but betrixaban appeared to confer benefit in another cohort and in the overall study population. Certain populations of patients, including the elderly, are at high risk for bleeding (mainly attributable to altered pharmacokinetics and polypharmacy); such patients are not appropriate candidates for extended-duration betrixaban therapy. Betrixaban can be a potential option for VTE prevention in medical patients; however, drug interaction potential and third-party coverage should be evaluated prior to prescribing.. Betrixaban is an oral option for VTE prevention in medical patients.

Topics: Anticoagulants; Benzamides; Clinical Trials, Phase II as Topic; Factor Xa Inhibitors; Hemorrhage; Humans; Meta-Analysis as Topic; Pyridines; Risk Factors; Venous Thromboembolism

Compared to other direct oral anticoagulants, betrixaban has a longer half-life, smaller peak-trough variance, minimal renal clearance, and minimal hepatic Cytochrome P (CYP) metabolism. The Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial evaluated the efficacy and safety of extended duration betrixaban compared to standard duration enoxaparin in acutely ill hospitalized patients. Areas covered: This article describes the role of betrixaban in the prevention of venous thromboembolism (VTE) in acutely ill medical patients. This article provides a consolidated summary of the primary APEX study findings as well as prespecified and exploratory substudies. This article also provides a review of the results of studies in which other direct factor Xa inhibitors have been evaluated in an extended duration regimen in this patient population. Expert commentary: While previous agents have demonstrated that extended duration VTE prophylaxis can be efficacious, betrixaban is the first agent to demonstrate efficacy without an increase in major bleeding. The totality of the data from the APEX trial supports extended duration betrixaban for VTE prophylaxis in the acute medically ill patient population. As such, betrixaban has been approved in the USA for extended VTE prophylaxis in at-risk acute medically ill patients.

Topics: Anticoagulants; Benzamides; Enoxaparin; Factor Xa Inhibitors; Hemorrhage; Humans; Pyridines; Risk Factors; Venous Thromboembolism

Despite significant advances in strategies and compliance with venous thromboembolism (VTE) prophylaxis, hospital-acquired VTE remains a leading cause of preventable deaths in acute medically ill patients. A majority of venous thromboembolic events occur posthospital discharge when risk factors persist and pharmacoprophylactic regimens have been completed. Until recently, there has been an unmet need for safe and effective extended-duration VTE prevention. Three major trials evaluated this concept, but excess bleeding outweighed the benefit of reduced thromboembolic events. Betrixaban is an oral direct factor Xa inhibitor recently approved for extended-duration VTE prophylaxis in acute medically ill patients at risk for thromboembolism based on results from the Phase III APEX study. This article reviews the pharmacology and supporting data for betrixaban.

Topics: Benzamides; Factor Xa Inhibitors; Humans; Pyridines; Venous Thromboembolism

Venous thromboembolism (VTE), comprising deep vein thrombosis and pulmonary embolism, is a serious clinical and public health concern. Hospitalization is a major risk factor for developing VTE. Hospital-associated events account for more than 50% of all cases of VTE. Heparins have demonstrated to be efficacious in the prevention of VTE in medically ill patients. Despite the demonstrated efficacy and safety of the available direct oral anticoagulants in the prevention and treatment of different thromboembolic conditions, their net benefit in the prevention of VTE in hospitalized medically ill patients has not been fully confirmed. Betrixaban is an oral, specific and direct inhibitor of human coagulation factor Xa with demonstrated efficacy and safety for the prevention of VTE in patients undergoing total knee replacement and in patients with nonvalvular atrial fibrillation. Recent studies have successfully evaluated betrixaban 80 mg once daily in the prevention of VTE in acute medically ill patients in a large phase III trial. This review will address preclinical pharmacology and main aspects of the clinical development of betrixaban as an antithrombotic agent, with specific attention to recent studies on the prophylaxis of VTE in a specific population of patients hospitalized for acute medical illnesses.

Topics: Acute Disease; Administration, Oral; Animals; Benzamides; Factor Xa; Factor Xa Inhibitors; Hospitalization; Humans; Pyridines; Risk Factors; Venous Thromboembolism

Appropriate treatment of venous thromboembolism (VTE) is critical to minimizing long-term morbidity and mortality. The emergence of direct oral anticoagulants (DOACs) has provided clinicians with expanded therapeutic options for patients with VTE, and as a result, updated practice guidelines released by the American College of Chest Physicians favor DOACs over traditional anticoagulants, such as warfarin. The newest DOAC, betrixaban, received FDA approval in 2017, with an indication for VTE prophylaxis in hospitalized adults. Additionally, results from the XALIA study on the real-world outcomes of rivaroxaban are now available. A reversal agent for dabigatran, idarucizumab, also received FDA approval in 2017, and other reversal agents are in development. This article will provide an overview of current VTE treatment strategies, with an emphasis on the place in therapy of the DOACs.

Topics: Administration, Oral; Anticoagulants; Benzamides; Dabigatran; Female; Humans; Incidence; Male; Prognosis; Pyridines; Risk Assessment; Rivaroxaban; Severity of Illness Index; Survival Rate; Treatment Outcome; Venous Thromboembolism; Warfarin

Approximately 900,000 people are affected by some sort of venous thromboembolic (VTE) event every year in the United States. VTE diagnosis used to mean treatment with medications that required routine lab monitoring for safety and efficacy. Activated factor X (FXa) inhibition has emerged as a convenient pathway for management of VTE and currently three FXa inhibitors are available for anticoagulation management - rivaroxaban, apixaban, and edoxaban. Continued development of medications utilizing this pathway may offer advantages via novel pharmacokinetic or pharmacodynamic properties that may minimize the adverse effects associated with traditional anticoagulant therapy. This review summarizes the available information regarding pharmacokinetic, pharmacodynamic, and early safety and efficacy data for three factor Xa inhibitors being developed - darexaban, betrixaban and nokxaban. The studies reviewed in this article suggests that three newer agents possess the potential for promise based on early phase I and II trials.

Topics: Administration, Oral; Animals; Azepines; Benzamides; Blood Coagulation; Drug Discovery; Factor Xa Inhibitors; Humans; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Thiazoles; Venous Thromboembolism

Venous thromboembolism is a major global health burden. Since the 1930s, prevention of stroke and pulmonary embolism in these patients has been achieved using conventional anticoagulants, such as heparin and warfarin. However, in recent years, four direct non-vitamin K antagonist oral anticoagulants (DOACs) have entered the market as alternative treatment options. Betrixaban is a fifth DOAC looking to gain marketing approval in the near future, and may have several potentially beneficial properties. Areas covered: Here, we outline the metabolism, pharmacokinetics, and pharmacodynamics of betrixaban, and summarise its clinical efficacy and safety based on the results of phase II/III trials. Expert commentary: Betrixaban has been demonstrated to have antithrombotic activity that may make it a valuable addition to the repertoire of DOACs currently available. The low renal clearance and minimal hepatic metabolism of the drug may make it particularly beneficial for patients with renal or hepatic dysfunction. The lack of an effective reversal agent may be a more significant issue for betrixaban compared with the already approved DOACs as it has a longer terminal half-life. Available data suggest that continued development of betrixaban is justified; however, further large randomised clinical trials are essential in order to clarify its efficacy and safety.

Topics: Administration, Oral; Anticoagulants; Benzamides; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Factor Xa Inhibitors; Humans; Pyridines; Treatment Outcome; Venous Thromboembolism

Venous thromboembolism (VTE), which includes deep vein thrombosis and pulmonary embolism, is a common and potentially preventable cause of morbidity and mortality. Unfractionated heparin, low-molecular-weight heparin, and warfarin have been the cornerstone of VTE prevention and treatment but are being replaced by recently approved non-vitamin K antagonist oral anticoagulants (NOACs): dabigatran, rivaroxaban, apixaban, and edoxaban. The NOACs are at least as effective and as safe as heparins and warfarin for VTE prevention and treatment and are more convenient because they have a low propensity for food and drug interactions and are given in fixed doses without routine coagulation monitoring. The remaining limitations of currently available NOACs include their dependence on renal and hepatic function for clearance, and the lack of an approved antidote. Betrixaban is a new NOAC with distinct pharmacological characteristics: minimal renal clearance, minimal hepatic metabolism, and long half-life. It has undergone successful Phase II studies in orthopedic thromboprophylaxis, and in stroke prevention in atrial fibrillation. Currently, it is being evaluated in a Phase III trial of extended thromboprophylaxis in medical patients (APEX study). In this article, we describe the development of betrixaban, review its pharmacological profile, discuss the results of clinical trials, and examine its potential for VTE prevention and treatment.

Topics: Administration, Oral; Animals; Benzamides; Clinical Trials, Phase II as Topic; Clinical Trials, Phase III as Topic; Disease Models, Animal; Factor Xa Inhibitors; Heparin; Humans; Pyridines; Venous Thromboembolism; Vitamin K; Warfarin

For over 60 years vitamin K antagonists have been the mainstay of oral therapy for treatment and prevention of venous and arterial thromboembolic disease. The emergence of two new classes of orally administered anticoagulants, direct thrombin and factor Xa inhibitors have drastically changed the landscape in the management of these disease states. Betrixaban , an orally administered direct factor Xa inhibitor, is entering a Phase III trial and undergoing investigation for similar indications as apixaban, dabigatran and rivaroxaban.. The chemical development of betrixaban, pharmacokinetic differences between betrixaban and currently available novel anticoagulants and future considerations for clinical use.. Betrixaban, the fifth novel oral anticoagulant in line for the Food and Drug Administration (FDA) approval, possesses some unique pharmacokinetic characteristics in comparison with the currently available novel anticoagulants, including limited renal excretion, minimal metabolism through the cytochrome p450 system and a long half-life. This pharmacokinetic profile may allow greater flexibility for use in patients with poor renal function, offer the convenience of once daily dosing, and exhibit less drug interactions. Betrixaban is currently being evaluated for prophylaxis against venous thromboembolic disease (VTED) and the prevention of stroke and systemic embolism associated with nonvalvular atrial fibrillation, its role in the management of acute VTED and acute coronary syndromes is yet to be defined based on clinical data and evaluation. Of interest, a factor Xa decoy, PRT4445, is currently under evaluation in conjunction with betrixaban, and may be a universal reversal agent for all anticoagulants with anti-Xa activity. Currently, there are no specific reversal agents for the novel anticoagulants. The availability of an effective reversal agent would be very attractive for the management of associated bleeding, bleeding due to trauma, or the need for emergent surgery.

Topics: Animals; Anticoagulants; Benzamides; Factor Xa Inhibitors; Humans; Pyridines; Treatment Outcome; Venous Thromboembolism

Heparin and low molecular weight heparins have limitations in their efficacy and safety for the prevention and treatment of venous thromboembolism (VTE). New synthetic antithrombotic drugs, designed with the intention of improving the therapeutic window for prophylaxis and treatment, are in various stages of development. Synthetic pentasaccharides include fondaparinux and its long-acting analogue idraparinux. Dabigatran is a direct thrombin inhibitor that has undergone clinical trials for VTE prophylaxis and treatment. Direct factor Xa inhibitors include rivaroxiban, which has shown promising results for VTE prophylaxis and is being studied for VTE treatment, as well as apixaban and betrixaban, which are at earlier stages of clinical validation. These newer agents may represent viable options for prophylaxis and therapy as further clinical studies are performed.

Topics: Anticoagulants; Benzamides; Benzimidazoles; beta-Alanine; Dabigatran; Fondaparinux; Humans; Morpholines; Oligosaccharides; Polysaccharides; Pyrazoles; Pyridines; Pyridones; Randomized Controlled Trials as Topic; Rivaroxaban; Thiophenes; Venous Thromboembolism

Venous thromboembolism (VTE) incurs substantial costs to the UK National Health Service (NHS). Betrixaban is approved in the US for VTE prophylaxis with a recommended 35-42 days of treatment. This analysis modeled the budget impact of introducing betrixaban for extended-duration VTE prophylaxis in nonsurgical patients with acute medical illness at risk of VTE in the UK, where it is not yet licensed.. The 5-year budget impact of introducing betrixaban into current prophylaxis (low molecular weight heparin and fondaparinux) was estimated for the UK NHS. The Phase 3 APEX study provided primary event (VTE, myocardial infarction, ischemic stroke, and death; all-cause or VTE-related) and treatment complications data. Literature informed risk of recurrent events and long-term complications, population, market share, and costs for treatment and management of events. Network meta-analyses informed symptomatic DVT, pulmonary embolism and VTE-related death rates in fondaparinux patients. Deterministic sensitivity analyses explored uncertainty.. Introducing betrixaban accrued savings of £1,290,000-£23,000,000 in years 1-5. Savings were from reduced primary VTE events, which reduced recurrent events and future complications. All sensitivity analyses showed savings.. Introducing extended-duration VTE prophylaxis with betrixaban in the UK would accrue substantial savings annually over the next 5 years compared to current prophylaxis. Clinical trial registration: www.clinicaltrials.gov identifier is NCT01583218.

Topics: Acute Disease; Adult; Aged; Benzamides; Budgets; Cost Savings; Factor Xa Inhibitors; Humans; Middle Aged; Models, Economic; Pyridines; Risk Factors; State Medicine; Time Factors; United Kingdom; Venous Thromboembolism

Extended-duration thromboprophylaxis with betrixaban reduces the risk of venous thromboembolism (VTE) without increasing major bleeding rates in acutely ill medical patients as compared to standard duration enoxaparin. We aimed to assess the risk-benefit of betrixaban in patients aged ≥ 80 years enrolled in the APEX trial.. APEX was a randomized, double-blind trial in which patients hospitalized for acute medical illnesses received enoxaparin 40 mg qd for 10 ± 4 days or oral betrixaban 80 mg qd for 35 to 42 days. The primary efficacy outcome was VTE, the principal safety outcome was major bleeding. Net clinical benefit (NCB) was defined by the occurrence of VTE or major bleeding.. Of 7513 patients enrolled in the APEX trial, 2781 (37%) were aged ≥ 80 years. In this subgroup, VTE or major bleeding occurred in 7.0% of betrixaban patients and in 8.4% of enoxaparin patients, for a relative risk in the NCB of 0.82 (95% confidence interval 0.62-1.10). The relative risk reduction obtained with betrixaban was similar between those aged ≥ 80 years and patients younger than 80 years (5.0% and 6.7%, respectively, NCB 0.75, 0.58-0.96, P = .024), with no significant interaction across age groups (P = .33).. Event rates were higher in medically ill patients aged ≥ 80 years enrolled in the APEX study than in patients younger than 80 years. The predefined NCB was reduced with extended betrixaban therapy in both groups with no signs of age-related interactions. However, the primary efficacy endpoint was not achieved with betrixaban for patients 80 years of age or older.

Topics: Administration, Oral; Adult; Aged; Aged, 80 and over; Anticoagulants; Benzamides; Blood Coagulation; Double-Blind Method; Drug Administration Schedule; Enoxaparin; Factor Xa Inhibitors; Female; Hemorrhage; Humans; Male; Middle Aged; Progression-Free Survival; Pyridines; Risk Assessment; Risk Factors; Time Factors; Venous Thromboembolism

To assess the efficacy and safety of betrixaban for venous thromboembolism (VTE) prophylaxis among critically ill patients.. The APEX trial randomized 7513 acutely ill hospitalized patients to betrixaban for 35-42 days or enoxaparin for 10 ± 4 days. Among those, 703 critically ill patients admitted to the intensive care unit were included in the analysis, and 547 patients who had no severe renal insufficiency or P-glycoprotein inhibitor use were included in the full-dose stratum. The risk of VTE, bleeding, net clinical benefit (composite of VTE and major bleeding), and mortality was compared at 35-42 days and at 77 days.. At 35-42 days, extended betrixaban reduced the risk of VTE (4.27% vs 7.95%, P = 0.042) without causing excess major bleeding (1.14% vs 3.13%, P = 0.07). Both VTE (3.32% vs 8.33%, P = 0.013) and major bleeding (0.00% vs 3.26%, P = 0.003) were decreased in the full-dose stratum. Patients who received betrixaban had more non-major bleeding than enoxaparin (overall population: 2.56% vs 0.28%, P = 0.011; full-dose stratum: 3.32% vs 0.36%, P = 0.010). Mortality was similar at the end of study (overall population: 13.39% vs 16.19%, P = 0.30; full-dose stratum: 13.65% vs 16.30%, P = 0.39).. Compared with shorter-duration enoxaparin, critically ill medical patients who received extended-duration betrixaban had fewer VTE without more major bleeding events. The benefit of betrixaban was driven by preventing asymptomatic thrombosis and offset by an elevated risk of non-major bleeding. The APEX trial did not stratify by intensive care unit admission and the present study included a highly selected population of critically ill patients. These hypothesis-generating findings need to be validated in future studies.. http://www.clinicaltrials.gov . Unique identifier: NCT01583218.

Topics: Adult; Aged; Aged, 80 and over; Anticoagulants; Benzamides; Critical Illness; Enoxaparin; Factor Xa Inhibitors; Female; Humans; Male; Middle Aged; Pre-Exposure Prophylaxis; Pyridines; Risk Factors; Time Factors; Venous Thromboembolism

Hospitalized acute medically ill patients with a history of venous thromboembolism (VTE) are at increased risk for recurrent VTE. We characterized the efficacy and safety of betrixaban for prevention of recurrent VTE in these high risk patients. The APEX trial randomized 7513 acutely ill hospitalized medical patients at risk for developing VTE to receive either betrixaban for 35-42 days or enoxaparin for 10 ± 4 days to prevent VTE. This exploratory post-hoc analysis assessed the efficacy and safety of betrixaban versus enoxaparin among subjects with and without prior VTE. Time-to-multiple symptomatic VTE events was also calculated. Approximately 8% of subjects in both arms had prior VTE, which was associated with a fourfold increase in adjusted risk of VTE [MV OR 4.03, 95% CI 3.06-5.30, p < 0.001]. Betrixaban reduced VTE compared with enoxaparin among subjects with prior VTE [32 (10.4%) vs. 55 (18.9%), RR 0.57, 95% CI 0.38-0.86, p = 0.006, ARR 8.5%, NNT 12] and without prior VTE [133 (3.9%) vs. 168 (4.9%), RR 0.79, 95% CI 0.64-0.99, p = 0.042, ARR 1.0%, NNT 100] (interaction p > 0.05). Additionally, four subjects in the enoxaparin arm and one subject in the betrixaban arm experienced a recurrent VTE. Compared with enoxaparin, betrixaban use was associated with reduction of recurrent VTE events through the active treatment period [36 vs. 57, HR 0.63, 95% CI 0.41-0.97, p = 0.045] and through the end of study [38 vs. 71, HR 0.54, 95% CI 0.36-0.81, p = 0.004]. Prior VTE is associated with a fourfold increase in the risk of VTE among hospitalized medically ill patients. Only 12 such patients would need to be treated with betrixaban versus enoxaparin to prevent an additional VTE endpoint. Betrixaban reduced not only the first but also all recurrent VTE events in a time-to-any-event analysis.. http://www.clinicaltrials.gov , Unique identifier: NCT01583218.

Topics: Adult; Aged; Benzamides; Enoxaparin; Female; Humans; Male; Middle Aged; Pyridines; Recurrence; Secondary Prevention; Treatment Outcome; Venous Thromboembolism

Topics: Anticoagulants; Benzamides; Double-Blind Method; Drug Administration Schedule; Enoxaparin; Factor Xa Inhibitors; Fibrinolytic Agents; Humans; Inpatients; Patient Readmission; Pyridines; Risk Factors; Time Factors; Treatment Outcome; Venous Thromboembolism

Approximately 15%-30% of patients in trials of medical thromboprophylaxis will have missing compression ultrasound (CUS) data. The goal of the present analysis was to perform analyses to minimize missing data.. The APEX trial randomized 7,513 acutely medically ill hospitalized patients to thromboprophylaxis with either betrixaban for 35-42 days or enoxaparin for 6-14 days. A modified intent-to-treat (mITT) analysis was performed and included all subjects administered study drug, irrespective of CUS performance, and an analysis of symptomatic events which do not require performance of a CUS (symptomatic deep vein thrombosis, nonfatal pulmonary embolism, and venous thromboembolism (VTE)-related mortality).. In the mITT population, betrixaban significantly reduced the primary end point (which included both symptomatic and CUS events) (165 [4.4%] vs 223 [6.0%]; relative risk = 0.75; 95% CI 0.61-0.91; P = .003; absolute risk reduction [ARR] = 1.6%; number needed to treat [NNT] = 63). Betrixaban also reduced symptomatic VTE through day 42 (35 [1.28%] vs 54 [1.88%], hazard ratio [HR] = 0.65; 95% CI 0.42-0.99; P = .044; ARR = 0.6%; NNT=167) as well as through day 77 (37 [1.02%] vs 67 [1.89%]; HR= 0.55; 95% CI 0.37-0.83; P = .003; ARR = 0.87%; NNT=115) as well as the individual end point of nonfatal pulmonary embolism (9 [0.25%] vs 20 [0.55%]; HR= 0.45; 95% CI 0.21-0.99; P = .041; ARR = 0.30%; NNT=334). On an "as-treated" basis, 80 mg of betrixaban reduced VTE-related mortality through day 77 (10 [0.34%] vs. 22 [0.79%]; HR=0.46; 95% CI 0.22-0.96; P = .035; ARR = 0.45%; NNT=223).. In an mITT analysis of all patients administered study drug, extended-duration betrixaban reduced the primary end point as well as symptomatic events. In an as-treated analysis, 80 mg of betrixaban reduced VTE-related death.

Topics: Acute Disease; Aged; Aged, 80 and over; Anticoagulants; Benzamides; Critical Illness; Dose-Response Relationship, Drug; Double-Blind Method; Drug Administration Schedule; Female; Hospitalization; Humans; Incidence; Intention to Treat Analysis; Kaplan-Meier Estimate; Male; Primary Prevention; Prognosis; Proportional Hazards Models; Pulmonary Embolism; Pyridines; Risk Assessment; Survival Analysis; Treatment Outcome; Venous Thromboembolism

Anemia is a common finding and independent predictor for adverse outcomes in hospitalized patients with medical illness. It remains unclear whether anemia is a risk factor for venous thromboembolism and whether the presence of anemia can refine risk assessment for prediction of venous thromboembolism, thereby adding incremental utility to a validated model.. In the Acute Medically Ill Venous Thromboembolism Prevention with Extended Duration Betrixaban trial (APEX), 7513 hospitalized medical patients were randomized to receive either betrixaban or standard-of-care enoxaparin for thromboprophylaxis. Baseline hemoglobin concentrations were obtained in 6861 patients, with a follow-up of 77 days. Symptomatic venous thromboembolism events, including symptomatic deep vein thrombosis, pulmonary embolism, and venous thromboembolism-related mortality, were compared between low-hemoglobin and normal-hemoglobin groups (normal range: 12.5-17.0 g/dL for males and 11.0-15.5 g/dL for females). The relationship between anemia and venous thromboembolism events was assessed by fitting a univariable and multivariable logistic regression model composed of thromboprophylaxis and risk factors. Venous thromboembolism risk refinement by hemoglobin measurement was evaluated in the International Medical Prevention Registry on Venous Thromboembolism (IMPROVE) risk assessment model.. Low hemoglobin at baseline was associated with a greater risk of symptomatic venous thromboembolism (relative risk [RR] 1.94 [95% confidence interval, 1.27-2.98]; P = .002), symptomatic deep vein thrombosis (RR 2.29 [1.12-4.68]; P = .019), and nonfatal pulmonary embolism (RR 2.63 [1.22-5.65]; P = .010) but not venous thromboembolism-related mortality (RR 1.47 [0.71-3.04]; P = .30). After adjusting for thromboprophylaxis, history of previous venous thromboembolism, intensive or coronary unit admission, and D-dimer, low hemoglobin (as a categorical or continuous variable) remained associated with an increased likelihood of venous thromboembolism (adjusted odds ratio 1.71 [95% confidence interval, 1.09-2.69]; P = .020). Low hemoglobin also improved risk discrimination and reclassification after inclusion in the IMPROVE model.. Anemia was independently associated with a greater risk of symptomatic venous thromboembolism among acutely ill medical patients despite the provision of thromboprophylaxis. Hemoglobin measurement also improved risk stratification by the IMPROVE venous thromboembolism risk score.

Topics: Acute Disease; Aged; Anemia; Benzamides; Double-Blind Method; Factor Xa Inhibitors; Female; Hemoglobins; Hospitalization; Humans; Male; Pyridines; Risk Assessment; Risk Factors; Venous Thromboembolism

 Asymptomatic deep vein thrombosis (DVT) diagnosed with compression ultrasound (CUS) is a common endpoint in trials assessing the efficacy of anticoagulants to prevent venous thromboembolism (VTE), but the relationship of asymptomatic thrombus to mortality remains uncertain..  In the APEX trial (ClinicalTrials.gov: NCT01583218), 7,513 acutely ill hospitalized medical patients were randomly assigned to extended-duration betrixaban (35-42 days) or enoxaparin (10 ± 4 days). Asymptomatic DVT was assessed once with CUS between day 32 and 47, and mortality was assessed through 77 days..  Asymptomatic DVT was associated with approximately threefold increased risk of short-term all-cause mortality in patients hospitalized with an acute medical illness within the prior 77 days. A positive linear trend was observed between greater thrombus burden and mortality during the follow-up.

Topics: Aged; Aged, 80 and over; Anticoagulants; Asymptomatic Diseases; Benzamides; Enoxaparin; Female; Humans; Male; Proportional Hazards Models; Pyridines; Risk; Survival Analysis; United States; Venous Thromboembolism; Venous Thrombosis

Extended-duration betrixaban showed a significant reduction in venous thromboembolism in the APEX trial (Acute Medically Ill VTE Prevention With Extended Duration Betrixaban Study). Given the variable clinical impact of different efficacy and safety events, one approach to assess net clinical outcomes is to include only those events that are either fatal or cause irreversible harm.. Among hospitalized medically ill patients, extended-duration betrixaban demonstrated an ≈30% reduction in fatal or irreversible ischemic or bleeding events compared with standard-duration enoxaparin. A total of 65 patients would require treatment with betrixaban to prevent 1 fatal or irreversible event versus enoxaparin.. URL: http://www.ClinicalTrials.gov. Unique identifier: NCT01583218.

Topics: Acute Disease; Adult; Aged; Anticoagulants; Benzamides; Cardiovascular Diseases; Double-Blind Method; Enoxaparin; Factor Xa Inhibitors; Female; Hemorrhage; Humans; Inpatients; Intracranial Hemorrhages; Kaplan-Meier Estimate; Male; Middle Aged; Proportional Hazards Models; Pyridines; Risk Factors; Time Factors; Treatment Outcome; Venous Thromboembolism

Competing risk methods are time-to-event analyses that account for fatal and/or nonfatal events that may potentially alter or prevent a subject from experiencing the primary endpoint. Competing risk methods may provide a more accurate and less biased estimate of the incidence of an outcome but are rarely applied in cardiology trials. APEX investigated the efficacy of extended-duration betrixaban versus standard-duration enoxaparin to prevent a composite of symptomatic deep-vein thrombosis (proximal or distal), nonfatal pulmonary embolism, or venous thromboembolism (VTE)-related death in acute medically ill patients (n = 7513). The aim of the current analysis was to determine the efficacy of betrixaban vs standard-duration enoxaparin accounting for non-VTE-related deaths using the Fine and Gray method for competing risks. The proportion of non-VTE-related death was similar in both the betrixaban (133, 3.6%) and enoxaparin (136, 3.7%) arms, P = .85. Both the traditional Kaplan-Meier method and the Fine and Gray method accounting for non-VTE-related death as a competing risk showed equal reduction of VTE events when comparing betrixaban to enoxaparin (HR/SHR = 0.65, 95% 0.42-0.99, P = 0.046). Due to the similar proportion of non-VTE-related deaths in both treatment arms and the use of a univariate model, the Fine and Gray method provided identical results to the traditional Cox model. Using the Fine and Gray method in addition to the traditional Cox proportional hazards method can indicate whether the presence of a competing risk, which is dependent of the outcome, altered the risk estimate.

Topics: Aged; Anticoagulants; Benzamides; Delayed-Action Preparations; Double-Blind Method; Enoxaparin; Factor Xa Inhibitors; Humans; Kaplan-Meier Estimate; Models, Statistical; Proportional Hazards Models; Pulmonary Embolism; Pyridines; Research Design; Risk; Risk Assessment; Venous Thromboembolism; Venous Thrombosis

The APEX trial assessed the safety and efficacy of extended-duration thromboprophylaxis using betrixaban versus standard dosing of enoxaparin among hospitalized, acutely ill medical patients. The 80-mg betrixaban dose was halved to 40 mg among subjects with severe renal insufficiency and those receiving a concomitant strong P-glycoprotein inhibitor.. This analysis assessed the pharmacokinetics, efficacy, and safety of full- (80 mg) and reduced-dose (40 mg) betrixaban relative to enoxaparin in the APEX trial.. The median concentration of betrixaban among subjects administered the 80-mg dose was higher than that of the 40-mg dose (19 ng/mL vs 11 ng/mL, P<.001). In the primary analysis cohort 1 (d-dimer ≥2× upper limit of normal), the primary efficacy outcome (asymptomatic proximal deep vein thrombosis, symptomatic proximal or distal deep vein thrombosis, symptomatic nonfatal pulmonary embolism, or venous thromboembolism-related death) was significantly reduced among subjects treated with 80 mg of extended-duration betrixaban versus enoxaparin (6.27% [95/1516] vs 8.39% [130/1549], relative risk reduction=0.26 [0.04-0.42], P=.023), and similarly in the entire primary efficacy outcome population (4.87% [122/2506] vs 7.06% [181/2562], relative risk reduction=0.30 [0.13-0.44], P=.001). There was no difference in the primary outcome for subjects treated with 40 mg betrixaban vs enoxaparin across cohorts. In addition, there was no excess of major bleeding associated with either betrixaban dose compared with enoxaparin.. The 80-mg betrixaban dose achieves higher plasma concentrations than the 40-mg dose and, in contrast to the 40-mg dose, is associated with improved efficacy across all cohorts relative to standard-dose enoxaparin without an excess risk of major bleeding in the management of medically ill subjects.

Topics: Aged; Aged, 80 and over; Anticoagulants; Benzamides; Double-Blind Method; Enoxaparin; Factor Xa Inhibitors; Female; Hemorrhage; Hospitalization; Humans; Male; Pulmonary Embolism; Pyridines; Venous Thromboembolism; Venous Thrombosis

Patients with acute medical illnesses are at prolonged risk for venous thrombosis. However, the appropriate duration of thromboprophylaxis remains unknown.. Patients who were hospitalized for acute medical illnesses were randomly assigned to receive subcutaneous enoxaparin (at a dose of 40 mg once daily) for 10±4 days plus oral betrixaban placebo for 35 to 42 days or subcutaneous enoxaparin placebo for 10±4 days plus oral betrixaban (at a dose of 80 mg once daily) for 35 to 42 days. We performed sequential analyses in three prespecified, progressively inclusive cohorts: patients with an elevated d-dimer level (cohort 1), patients with an elevated d-dimer level or an age of at least 75 years (cohort 2), and all the enrolled patients (overall population cohort). The statistical analysis plan specified that if the between-group difference in any analysis in this sequence was not significant, the other analyses would be considered exploratory. The primary efficacy outcome was a composite of asymptomatic proximal deep-vein thrombosis and symptomatic venous thromboembolism. The principal safety outcome was major bleeding.. A total of 7513 patients underwent randomization. In cohort 1, the primary efficacy outcome occurred in 6.9% of patients receiving betrixaban and 8.5% receiving enoxaparin (relative risk in the betrixaban group, 0.81; 95% confidence interval [CI], 0.65 to 1.00; P=0.054). The rates were 5.6% and 7.1%, respectively (relative risk, 0.80; 95% CI, 0.66 to 0.98; P=0.03) in cohort 2 and 5.3% and 7.0% (relative risk, 0.76; 95% CI, 0.63 to 0.92; P=0.006) in the overall population. (The last two analyses were considered to be exploratory owing to the result in cohort 1.) In the overall population, major bleeding occurred in 0.7% of the betrixaban group and 0.6% of the enoxaparin group (relative risk, 1.19; 95% CI, 0.67 to 2.12; P=0.55).. Among acutely ill medical patients with an elevated d-dimer level, there was no significant difference between extended-duration betrixaban and a standard regimen of enoxaparin in the prespecified primary efficacy outcome. However, prespecified exploratory analyses provided evidence suggesting a benefit for betrixaban in the two larger cohorts. (Funded by Portola Pharmaceuticals; APEX ClinicalTrials.gov number, NCT01583218.).

Topics: Acute Disease; Adult; Aged; Benzamides; Double-Blind Method; Drug Administration Schedule; Factor Xa Inhibitors; Female; Fibrin Fibrinogen Degradation Products; Hemorrhage; Hospitalization; Humans; Male; Middle Aged; Pulmonary Embolism; Pyridines; Risk Factors; Ultrasonography; Venous Thromboembolism; Venous Thrombosis

Topics: Administration, Oral; Benzamides; Causality; Comorbidity; Enoxaparin; Fibrinolytic Agents; Humans; Myocardial Infarction; Prevalence; Pyridines; Treatment Outcome; Venous Thromboembolism

Randomized clinical trials have identified a population of acute medically ill patients who remain at risk for venous thromboembolism (VTE) beyond the standard duration of therapy and hospital discharge. The aim of the APEX study is to determine whether extended administration of oral betrixaban (35-42 days) is superior to a standard short course of prophylaxis with subcutaneous enoxaparin (10 ± 4 days followed by placebo) in patients with known risk factors for post-discharge VTE. Patients initially are randomized to receive either betrixaban or enoxaparin (and matching placebo) in a double dummy design. Following a standard duration period of enoxaparin treatment (with placebo tablets) or betrixaban (with placebo injections), patients receive only betrixaban (or alternative matching placebo). Patients are considered for enrollment if they are older than 40 years, have a specified medical illness, and restricted mobility. They must also meet the APEX criteria for increased VTE risk (aged ≥75 years, baseline D-Dimer ≥2× upper the limit of "normal", or 2 additional ancillary risk factors for VTE). The primary efficacy end point is the composite of asymptomatic proximal deep venous thrombosis, symptomatic deep venous thrombosis, non-fatal (pulmonary embolus) pulmonary embolism, or VTE-related death through day 35. The primary safety outcome is the occurrence of major bleeding. We hypothesize that extended duration betrixaban VTE prophylaxis will be safe and more effective than standard short duration enoxaparin in preventing VTE in acute medically ill patients with known risk factors for post hospital discharge VTE.

Topics: Acute Disease; Adult; Aged; Aged, 80 and over; Anticoagulants; Benzamides; Double-Blind Method; Enoxaparin; Factor Xa Inhibitors; Humans; Internationality; Middle Aged; Prospective Studies; Pyridines; Risk Factors; Time Factors; Treatment Outcome; Venous Thromboembolism

Patients hospitalized for an acute medical illness remain at risk of developing venous thromboembolism (VTE) post-discharge. Betrixaban, an oral direct Factor Xa inhibitor, is approved for extended VTE thromboprophylaxis in acutely ill medical patients. The primary objective of this study was to evaluate patients re-admitted with VTE within 30 days of discharge to determine if they would have been eligible for extended duration VTE prophylaxis during the index admission. We used three different sets of eligibility criteria: the APEX study criteria, the Bevyxxa® (betrixaban) package insert, and Mass General Brigham HealthCare System's Center for Drug Policy Guidelines. A secondary aim was to describe the reasons for ineligibility. Within 30 days of the index hospital admission, 226 patients were re-admitted with new VTE between January 2017 and December 2018. Of these, 134 (59%) were excluded based on pre-defined exclusion criteria. Of the remaining 92, 22 patients (23.9%) were eligible based on the APEX study criteria, 26 patients (28.2%) based on Mass General Brigham HealthCare System's Center for Drug Policy Guidelines, and 92 patients (100%) based on the Bevyxxa® package insert. There were 22 patients (23.9%) who were eligible for VTE prophylaxis with betrixaban based on all three criteria. Appropriate betrixaban use may have prevented some of the VTE events and re-admissions that occurred within 30 days of initial hospital discharge.

Topics: Aftercare; Anticoagulants; Benzamides; Hospitalization; Humans; Patient Discharge; Pharmaceutical Preparations; Pyridines; Risk Factors; Venous Thromboembolism

Hospitalized patients with acute medical illnesses are at risk for venous thromboembolism (VTE) during and after a hospital stay. Risk factors include physical immobilization and underlying pathophysiologic processes that activate the coagulation pathway and are still present after discharge. Strategies for optimal pharmacologic VTE thromboprophylaxis are evolving, and recommendations for VTE prophylaxis can be further refined to protect high-risk patients after hospital discharge. An early study of extended VTE prophylaxis with a parenteral agent in medically ill patients yielded inconclusive results with regard to efficacy and bleeding. In the Acute Medically Ill VTE Prevention with Extended Duration Betrixaban (APEX) trial, extended use of betrixaban halved symptomatic VTE, decreased hospital readmission, and reduced stroke and major adverse cardiovascular events compared with standard enoxaparin prophylaxis. Based on findings from APEX, the Food and Drug Administration approved betrixaban in 2017 for extended VTE prophylaxis in acute medically ill patients. In the Reducing Post-Discharge Venous Thrombo-Embolism Risk (MARINER) study, extended use of rivaroxaban halved symptomatic VTE in high-risk medical patients compared with placebo. In 2019, rivaroxaban was approved for extended thromboprophylaxis in high-risk medical patients, thus making available a new strategy for in-hospital and post-discharge VTE prevention. To address the critical unmet need for VTE prophylaxis in medically ill patients at the time of hospital discharge, the North American Thrombosis Forum (NATF) is launching the Anticoagulation Action Initiative, a comprehensive consensus document that provides practical guidance and straightforward, patient-centered recommendations for VTE prevention during hospitalization and after discharge.

Topics: Adult; Aged; Anticoagulants; Benzamides; Hospitalization; Humans; Medication Adherence; Middle Aged; Patient Discharge; Practice Guidelines as Topic; Pyrazoles; Pyridines; Pyridones; Risk Assessment; Risk Factors; Rivaroxaban; Venous Thromboembolism

Topics: Aftercare; Anticoagulants; Benzamides; Duration of Therapy; Enoxaparin; Heparin, Low-Molecular-Weight; Hospitalization; Humans; Length of Stay; Pulmonary Embolism; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Venous Thromboembolism; Venous Thrombosis

Hypoalbuminemia is a common finding and independent predictor for unfavorable prognosis. The prognostic value of albumin measurement for short-term VTE prediction in hospitalized patients remains unclear. In the APEX trial (ClinicalTrials.gov identifier: NCT01583218), medical inpatients were randomized to receive either extended-duration betrixaban or shorter-duration enoxaparin and followed for 77 days. Baseline albumin concentrations were obtained in 7266 subjects with evaluable VTE endpoints. The association of baseline albumin to VTE was assessed, with adjustment for patient characteristics, thromboprophylaxis, and biomarkers for fibrinolysis and inflammation (ie, D-dimer and C-reactive protein [CRP]). VTE risk refinement was evaluated by incorporation of albumin to well-validated risk assessment models. A stepwise increase in the risk of VTE (P < .0001) was observed with lower levels of albumin. Patients at the bottom albumin quartile (<35 g/L) had a two-fold greater odds for developing VTE compared with the top quartile (≥42 g/L) (OR = 2.119 [95% CI, 1.592-2.820]; adjusted OR = 2.079 [1.485-2.911]). The odds for VTE increased by 1.368 (95% CI, 1.240-1.509) times per SD decrement of albumin (5.24 g/L). Compared with the propensity score-matched pairs of patients with albumin ≥35 g/L, patients with albumin <35 g/L had a greater risk of VTE (OR = 1.623 [1.260-2.090]; adjusted OR = 1.658 [1.209-2.272]). Albumin measurement also refined VTE risk discrimination and reclassification after inclusion in the risk assessment models. In conclusion, acutely ill hospitalized patients with low serum albumin had an increased VTE risk through 77 days. VTE risk assessment models for medical inpatients should consider incorporation of baseline albumin measurement.

Topics: Acute Disease; Aged; Aged, 80 and over; Anticoagulants; Benzamides; C-Reactive Protein; Double-Blind Method; Enoxaparin; Female; Fibrin Fibrinogen Degradation Products; Hospitalization; Humans; Hypoalbuminemia; Immobilization; Inpatients; Length of Stay; Male; Middle Aged; Multicenter Studies as Topic; Pulmonary Embolism; Pyridines; Randomized Controlled Trials as Topic; Retrospective Studies; Risk; Serum Albumin; Venous Thromboembolism

Studies show that the risk of venous thromboembolism (VTE) continues post-discharge in nonsurgical patients with acute medical illness. Betrixaban is the first anticoagulant approved in the United States (US) for VTE prophylaxis extending beyond hospitalization.. The aim was to establish whether betrixaban for VTE prophylaxis in nonsurgical patients with acute medical illness at risk of VTE in the US is cost-effective compared with enoxaparin.. A cost-effectiveness analysis was conducted, estimating the cost per quality-adjusted life-year (QALY) gained with betrixaban (35-42 days) compared with enoxaparin (6-14 days) from a US payer perspective over a lifetime horizon. A decision tree (DT) estimated primary VTE events, thrombotic events, and treatment complications in the first 3 months based on data from the phase III Acute Medically Ill VTE Prevention with Extended Duration Betrixaban study. A Markov model estimated recurrent events and long-term complication risks from published literature. EuroQoL-5 Dimensions utility data and costs inflated to 2017 US dollars (US$) were from published literature. Results were discounted at 3.0% per annum. Deterministic and probabilistic sensitivity analyses explored uncertainty.. Betrixaban dominated enoxaparin, with savings of US$784 and increased QALYs of 0.017 per patient. In addition, betrixaban dominated enoxaparin across all sensitivity analyses, but was most sensitive to utilities and DT probabilities. Furthermore, probabilistic sensitivity analysis found that betrixaban was more cost-effective than enoxaparin at all willingness-to-pay thresholds.. Betrixaban can be considered cost-effective for nonsurgical patients with acute medical illness at risk of VTE, requiring longer VTE prophylaxis from hospitalization through post-discharge.

Topics: Acute Disease; Adult; Aged; Benzamides; Cost-Benefit Analysis; Decision Support Techniques; Decision Trees; Enoxaparin; Factor Xa Inhibitors; Humans; Markov Chains; Middle Aged; Primary Prevention; Pyridines; Quality-Adjusted Life Years; Venous Thromboembolism

Topics: Anticoagulants; Benzamides; Critical Illness; Enoxaparin; Humans; Pyridines; Venous Thromboembolism

Topics: Administration, Oral; Benzamides; Blood Coagulation; Drug Interactions; Factor Xa Inhibitors; Hospitalization; Humans; Mobility Limitation; Pyridines; Treatment Outcome; Venous Thromboembolism

Topics: Anticoagulants; Benzamides; Factor Xa Inhibitors; Hospitalization; Humans; Primary Prevention; Pyridines; Risk Assessment; Risk Factors; Transitional Care; United States; Venous Thromboembolism

Topics: Acute Disease; Aged; Benzamides; Factor Xa Inhibitors; Female; Health Care Costs; Hospitalization; Humans; Male; Primary Prevention; Pyridines; Randomized Controlled Trials as Topic; Risk Factors; United States; Venous Thromboembolism

Essentials Anticoagulants prevent venous thromboembolism but may be associated with greater bleeding risks. Bivariate analysis assumes a non-linear relationship between efficacy and safety outcomes. Extended full-dose betrixaban is favorable over standard enoxaparin in bivariate endpoint. Clinicians must weigh efficacy and safety outcomes in decision-making on thromboprophylaxis.. Background Among acutely ill hospitalized medical patients, extended-duration thromboprophylaxis reduces the risk of venous thromboembolism (VTE), but some pharmacologic strategies have been associated with greater risks of major bleeding, thereby offsetting the net clinical benefit (NCB). Methods To assess the risk-benefit profile of anticoagulation regimens, a previously described bivariate method that does not assume a linear risk-benefit tradeoff and can accommodate different margins for efficacy and safety was performed to simultaneously assess efficacy (symptomatic VTE) and safety (major bleeding) on the basis of data from four randomized controlled trials of extended-duration (30-46 days) versus standard-duration (6-14 days) thromboprophylaxis among 28 227 patients (EXCLAIM, ADOPT, MAGELLAN and APEX trials). Results Extended thromboprophylaxis with full-dose betrixaban (80 mg once daily) was superior in efficacy and non-inferior in safety to standard-duration enoxaparin, and showed a significantly favorable NCB, with a risk difference of - 0.51% (- 0.89% to - 0.10%) in the bivariate outcome. Extended enoxaparin was superior in efficacy and inferior in safety (bivariate outcome: 0.03% [- 0.37% to 0.43%]), whereas apixaban and rivaroxaban were non-inferior in efficacy and inferior in safety (- 0.20% [- 0.49% to 0.17%] and 0.23% [- 0.16% to 0.69%], respectively). Reduced-dose betrixaban did not show a significant difference in either efficacy or safety (0.41% [- 0.85% to 1.94%]). Conclusions In a bivariate analysis that assumes non-linear risk-benefit tradeoffs, extended prophylaxis with full-dose betrixaban was superior to standard-duration enoxaparin, whereas other regimens failed to simultaneously achieve both superiority and non-inferiority with respect to symptomatic VTE and major bleeding in the management of acutely ill hospitalized medical patients.

Topics: Acute Disease; Anticoagulants; Benzamides; Clinical Decision-Making; Clinical Trials, Phase III as Topic; Clinical Trials, Phase IV as Topic; Drug Administration Schedule; Enoxaparin; Hemorrhage; Hospitalization; Humans; Multivariate Analysis; Nonlinear Dynamics; Pyrazoles; Pyridines; Pyridones; Randomized Controlled Trials as Topic; Risk Assessment; Risk Factors; Rivaroxaban; Time Factors; Treatment Outcome; Venous Thromboembolism

Stroke is a morbid and potentially mortal complication among patients hospitalized with acute medical illness. The potential of extended-duration thromboprophylaxis with the factor Xa inhibitor betrixaban to reduce the risk of stroke compared with standard-dose enoxaparin in this population was assessed in this retrospective APEX trial substudy (Acute Medically Ill Venous Thromboembolism Prevention With Extended Duration Betrixaban).. Hospitalized acutely medically ill subjects (n=7513) were randomized in a double-dummy double-blind fashion to either extended-duration oral betrixaban (80 mg once daily for 35-42 days) or standard-dose subcutaneous enoxaparin (40 mg once daily for 10±4 days) for venous thromboprophylaxis. Stroke events were adjudicated by an independent, blinded event adjudication committee.. The mean age of study participants was 76 years; 45% were male; 13% had had a stroke; and 45% had congestive heart failure. There were fewer all-cause strokes (0.54% versus 0.97%; relative risk [RR]=0.56; 95% confidence interval, 0.32-0.96;. Among hospitalized medically ill patients, extended-duration betrixaban significantly reduced all-cause stroke and ischemic stroke through 77 days of follow-up CLINICAL TRIAL REGISTRATION: URL: http://www.clinicaltrials.gov. Unique identifier: NCT01583218.

Topics: Aged; Anticoagulants; Benzamides; Enoxaparin; Female; Humans; Male; Pyridines; Stroke; Venous Thromboembolism

Topics: Anticoagulants; Benzamides; Clinical Trials as Topic; Humans; Pyridines; Venous Thromboembolism

The recently introduced oral anticoagulants, dabigatran, rivaroxaban and apixaban, were shown, in randomized controlled trials, to be at least as effective and safe as monitored warfarin therapy for the treatment of venous thromboembolism and stroke prevention in atrial fibrillation. These new oral anticoagulants have predictable pharmacology, less variability in anticoagulant effect and fewer drug and food interactions than warfarin, allowing unmonitored and fixed dosing, which renders their use appealing. The remaining limitations of currently available new oral anticoagulants include their dependence on renal and hepatic clearance, and the lack of an antidote, which is problematic in bleeding patients and those requiring urgent surgery. Betrixaban is a new direct factor Xa inhibitor with distinct pharmacological characteristics, including a long half-life, minimal renal clearance and minimal hepatic metabolism. Betrixaban was tested in Phase II studies in orthopedic thromboprophylaxis (EXPERT) and atrial fibrillation (EXPLORE-Xa), and is being evaluated in a Phase III trial of extended thromboprophylaxis in medical patients (APEX). This article details the pharmacology, preclinical and clinical development of betrixaban.

Topics: Atrial Fibrillation; Benzamides; Blood Coagulation; Dose-Response Relationship, Drug; Drug Administration Schedule; Humans; Pyridines; Stroke; Venous Thromboembolism