betrixaban and apixaban

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

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

Intracerebral hemorrhage is a major source of morbidity and mortality, accounting for 10% of all strokes. Oral anticoagulation therapy, while necessary to prevent thromboembolic complications, increases the risk of intracerebral hemorrhage and can potentially worsen bleeding in cases of acute hemorrhage. Before the introduction of direct oral anticoagulant agents in 2010, warfarin was the only option for oral anticoagulation. These new agents have an improved safety profile compared with warfarin but require different reversal strategies. Anticoagulation reversal in the setting of acute intracerebral hemorrhage is an evolving field. This article covers the most common direct oral anticoagulant medications, various available anticoagulant reversal strategies, and the latest guidelines for anticoagulation reversal in patients with acute intracranial hemorrhage.

Topics: Administration, Oral; Anticoagulants; Antithrombins; Benzamides; Dabigatran; Humans; Intracranial Hemorrhages; Practice Guidelines as Topic; Pyrazoles; Pyridines; Pyridones; Risk Assessment; Rivaroxaban; Thromboembolism; Treatment Outcome

The purpose of this review was to offer practical management strategies for when patients receiving direct oral anticoagulants require elective surgery or present with bleeding complications.. Clinical practice guidelines are now available on the timing of periprocedural interruption of treatment with the newer direct oral anticoagulants based on their pharmacodynamics and pharmacokinetics and based on findings from cohort studies and clinical trials. An antibody that reverses the effects of dabigatran is now available, and a factor Xa decoy is being developed as an antidote to apixaban, betrixaban, edoxaban, and rivaroxaban. The timing of interruption of direct oral anticoagulants for elective surgery is based on multiple factors, including pharmacologic properties and interactions, the patient's renal function, and the type of planned surgery. There is little role for low-molecular-weight heparin bridging. Idarucizumab is the treatment of choice for dabigatran-related life-threatening bleeding, while andexanet alfa is being developed to reverse factor Xa inhibitors.

Topics: Administration, Oral; Antibodies, Monoclonal, Humanized; Anticoagulants; Antidotes; Antithrombins; Benzamides; Blood Loss, Surgical; Dabigatran; Deprescriptions; Elective Surgical Procedures; Factor Xa; Factor Xa Inhibitors; Hemorrhage; Humans; Practice Guidelines as Topic; Pyrazoles; Pyridines; Pyridones; Recombinant Proteins; Rivaroxaban; Thiazoles

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

Several new anticoagulants have entered the clinical arena or are under clinical development. These drugs include indirect (fondaparinux) and direct oral factor Xa inhibitors (rivaroxaban, apixaban, edoxaban, betrixaban), and the direct thrombin inhibitor dabigatran. Especially the oral direct FXa and FIIa inhibitors overcome many of the shortcomings of heparins and vitamin K antagonists (VKAs). They are administered orally at a fixed dose; regular monitoring is not necessary; interaction with other drugs or nutrition occur less than with VKAs and they are at least as effective as VKAs for most indications tested. They are associated with about 50 % less intracranial bleeding than VKAs. Nevertheless, they are still associated with bleeding complications. Bleeding can occur spontaneously or as a result of trauma or urgent surgery. In such situations rapid reversal of the anticoagulant effect is highly desirable. For unfractionated heparin protamine, and for VKAs prothrombin complex concentrates are available as specific antidotes. Under clinical development are: for the direct and indirect FXa inhibitors a modified recombinant FXa (andexanet alpha), which lacks enzymatic activity; and for dabigatran a Fab fragment of a monoclonal antibody (idarucizumab). In addition a small molecule (aripazine) has entered phase I clinical trials, which seems to inhibit nearly all anticoagulants but VKAs and argatroban. This review summarises the current options and strategies in development to antagonise anticoagulants with a focus on the status of the development of antidotes for the oral direct FXa and FIIa inhibitors.

Topics: Administration, Oral; Animals; Antibodies, Monoclonal; Antibodies, Monoclonal, Humanized; Anticoagulants; Antithrombins; Benzamides; Clinical Trials as Topic; Dabigatran; Factor Xa; Factor Xa Inhibitors; Fondaparinux; Hemorrhage; Hemostatics; Heparin; Humans; Infusions, Parenteral; Intracranial Hemorrhages; Polysaccharides; Protamines; Pyrazoles; Pyridines; Pyridones; Recombinant Proteins; Rivaroxaban; Thiazoles; Thrombosis; Vitamin K

Heparins and vitamin K antagonists (VKA) used commonly are the standard treatment of venous and arterial thromboses. They are very efficient and safe, but have some limitations: iatrogenicity, laboratory monitoring, parenteral use for heparins and fondaparinux. Nowadays, four new inhibitors of factor Xa are used orally (rivaroxaban, apixaban, edoxaban, betrixaban), and they are at least as efficient as heparins and vitamin K antagonists. The objective is to substitute these indirect inhibitors of factor Xa (heparins, low molecular weight heparins and fondaparinux) in the prevention of venous and arterial thromboembolic episodes. The new direct inhibitors do not require routine laboratory monitoring of blood coagulation. They inhibit the extrinsic and the intrinsic pathways of blood coagulation. Rivaroxaban and apixaban are efficacious and safe in the prevention of cerebral infarcts in patients with non-valvular fibrillation. Apixaban is another direct inhibitor of factor Xa used orally which is developed in the same indications as rivaroxaban. Edoxaban and betrixaban are also in development. The objective of this work is to study the pharmacodynamic, pharmacokinetic, the efficacy and safety of these four oral direct factor Xa inhibitors.

Topics: Acute Coronary Syndrome; Administration, Oral; Anticoagulants; Benzamides; Blood Coagulation; Embolism; Factor Xa Inhibitors; Hemorrhage; Hemostatics; Humans; Morpholines; Postoperative Complications; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Stroke; Thiazoles; Thiophenes; Thrombophilia; Thrombosis

New oral factor Xa inhibitors are intended to progressively substitute the oral vitamin K antagonists and parenteral indirect inhibitors of factor Xa in the prevention and treatment of venous and arterial thromboembolic episodes. This article focuses on the main clinical studies and on biological measurements of new oral factor Xa inhibitors, and addresses several safety issues. These newer agents do not require any routine laboratory monitoring of blood coagulation; however, biological tests have been developed in order to assess the plasma concentration of these drugs in several clinical settings. This article reviews these 4 oral direct factor Xa inhibitors.

Topics: Administration, Oral; Benzamides; Blood Coagulation Tests; Drug Monitoring; Factor Xa Inhibitors; Hemorrhage; Humans; Morpholines; Precision Medicine; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Thiazoles; Thiophenes

Warfarin has been the effective treatment in the prophylaxis of cardioembolism, in particular in patients with atrial fibrillation, for more than 50 years. Nevertheless, many patients with atrial fibrillation are not currently treated because of the numerous limits of oral anticoagulation and in those treated the quality of anticoagulation is often poor. Novel oral anticoagulant drugs, the direct thrombin antagonist dabigatran and factor Xa inhibitors such as rivaroxaban, apixaban, edoxaban, and betrixaban are more predictable and convenient anticoagulants in comparison with warfarin, mainly because of the non-requirement of regular laboratory monitoring and dose adjustments. Current data from phase III clinical trials are available for dabigatran, rivaroxaban and apixaban, which show to be at least noninferior in efficacy to warfarin for the prevention of stroke in patients with atrial fibrillation. This review focuses on the potential of novel anticoagulants to replace warfarin in patients with atrial fibrillation. Also the place in therapy and the potential limitations of the new agents in clinical practice represent important issues to be considered. The promise of new oral anticoagulants gives us the hope that warfarin will finally be replaced in a near future, but more importantly that anticoagulant undertreatment of atrial fibrillation will be partially overcome.

Topics: Administration, Oral; Anticoagulants; Atrial Fibrillation; Benzamides; Benzimidazoles; beta-Alanine; Clinical Trials, Phase III as Topic; Dabigatran; Evidence-Based Medicine; Humans; Morpholines; Pyrazoles; Pyridines; Pyridones; Risk Assessment; Rivaroxaban; Thiazoles; Thiophenes; Thromboembolism; Treatment Outcome; Warfarin

Prevention of stroke and systemic emboli is paramount in the management of atrial fibrillation. Although warfarin is the predominant anticoagulant used in patients with atrial fibrillation, it has significant limitations that have impeded appropriate use of stroke prophylaxis in eligible patients with atrial fibrillation. Consequently, much research has been focused on finding an alternative to warfarin. We review the potential alternatives in development and evaluate the current evidence concerning their safety and efficacy.. Oral direct factor Xa inhibitors are potentially well tolerated and effective replacements for warfarin. These agents do not require cofactors and offer selective inhibition at a critical step of amplification in the coagulation cascade. Multiple direct anti-factor Xa agents are currently undergoing evaluation in phase I, II, and III trials. Early results suggest that these novel anticoagulants have favorable pharmacokinetic and pharmacodynamic profiles with minimal-to-no requirements for therapeutic monitoring. Two direct factor Xa inhibitors are emerging from phase II trials (betrixaban and YM150) and three are being evaluated in phase III trials (apixaban, edoxaban, and rivaroxaban) for the prevention of stroke and systemic emboli in patients with atrial fibrillation. The phase III trials of apixaban and rivaroxaban have completed enrollment and are in the follow-up phase.. Given the growing population of patients with atrial fibrillation, there is a great interest in finding new therapies for oral anticoagulation. The direct factor Xa inhibitors may offer several promising alternatives to warfarin therapy.

Topics: Anticoagulants; Atrial Fibrillation; Benzamides; Factor Xa Inhibitors; Fibrinolytic Agents; Humans; Morpholines; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Stroke; Thiazoles; Thiophenes; Thromboembolism; Warfarin

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

Atrial fibrillation is already the most common clinically significant cardiac arrhythmia and a common cause of stroke. Vitamin K antagonists are very effective for the prevention of cardioembolic stroke but have numerous limitations that limit their uptake in eligible patients with AF and reduce their effectiveness in treated patients. Multiple new anticoagulants are under development as potential replacements for vitamin K antagonists. Most are small synthetic molecules that target factor IIa (e.g., dabigatran etexilate, AZD-0837) or factor Xa (e.g., rivaroxaban, apixaban, betrixaban, DU176b, idrabiotaparinux). These drugs have predictable pharmacokinetics that allow fixed dosing without laboratory monitoring, and are being compared with vitamin K antagonists or aspirin in phase III clinical trials [corrected]. A new vitamin K antagonist (ATI-5923) with improved pharmacological properties compared with warfarin is also being evaluated in a phase III trial. None of the new agents have as yet been approved for clinical use.

Topics: Anticoagulants; Atrial Fibrillation; Benzamides; Benzimidazoles; Biotin; Clinical Trials, Phase III as Topic; Dabigatran; Factor Xa Inhibitors; Humans; Morpholines; Oligosaccharides; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Thiazoles; Thiophenes; Vitamin K

Based on previous large-scale in silico screening several factor Xa inhibitors were proposed to potentially inhibit SARS-CoV-2 Mpro. In addition to their known anticoagulants activity this potential inhibition could have an additional therapeutic effect on patients with COVID-19 disease. In this study we examined the binding of the Apixaban, Betrixaban and Rivaroxaban to the SARS-CoV-2 Mpro with the use of the MicroScale Thermophoresis technique. Our results indicate that the experimentally measured binding affinity is weak and the therapeutic effect due to the SARS-CoV-2 Mpro inhibition is rather negligible.

Topics: Benzamides; Binding Sites; Coronavirus M Proteins; COVID-19; COVID-19 Drug Treatment; Factor Xa Inhibitors; Humans; Molecular Dynamics Simulation; Protein Binding; Protein Stability; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; SARS-CoV-2

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

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

Inhibitors of coagulation factor Xa (fXa) have emerged as a new class of antithrombotics but lack effective antidotes for patients experiencing serious bleeding. We designed and expressed a modified form of fXa as an antidote for fXa inhibitors. This recombinant protein (r-Antidote, PRT064445) is catalytically inactive and lacks the membrane-binding γ-carboxyglutamic acid domain of native fXa but retains the ability of native fXa to bind direct fXa inhibitors as well as low molecular weight heparin-activated antithrombin III (ATIII). r-Antidote dose-dependently reversed the inhibition of fXa by direct fXa inhibitors and corrected the prolongation of ex vivo clotting times by such inhibitors. In rabbits treated with the direct fXa inhibitor rivaroxaban, r-Antidote restored hemostasis in a liver laceration model. The effect of r-Antidote was mediated by reducing plasma anti-fXa activity and the non-protein bound fraction of the fXa inhibitor in plasma. In rats, r-Antidote administration dose-dependently and completely corrected increases in blood loss resulting from ATIII-dependent anticoagulation by enoxaparin or fondaparinux. r-Antidote has the potential to be used as a universal antidote for a broad range of fXa inhibitors.

Topics: Animals; Anticoagulants; Antidotes; Benzamides; Dose-Response Relationship, Drug; Enoxaparin; Factor Xa; Factor Xa Inhibitors; Fondaparinux; Hemorrhage; Hemostasis; Male; Mice; Mice, Inbred C57BL; Morpholines; Polysaccharides; Pyrazoles; Pyridines; Pyridones; Rabbits; Rats; Rats, Sprague-Dawley; Recombinant Proteins; Rivaroxaban; Thiophenes

Introduction Over the past 60 years, clinicians have used vitamin K antagonists, primarily warfarin, as the sole oral anticoagulants for managing a variety of thrombotic disorders. Warfarin, which requires frequent monitoring, has a variable dose response, a narrow therapeutic index, and numerous drug and dietary interactions. However, intravenous and subcutaneous agents, such as unfractionated heparin, low-molecular-weight heparin, direct thrombin inhibitors, and pentasaccharide, have been introduced over the past 30 years for managing thromboembolic disorders. Recently, 5 new oral anticoagulants, dabigatran, rivaroxaban, apixaban, endoxaban, and betrixaban, have been introduced into clinical trials. Apixaban, rivaroxaban, endoxaban, and betrixaban are specific direct inhibitors of factor Xa, while dabigatran inhibits factor IIa. These drugs have a pharmacological profile that does not require monitoring in order to adjust therapy, which is the mainstay of warfarin management. In addition, these new medications have not shown any major issues regarding food interactions; rather, they demonstrate the potential for limited drug-drug interactions due to their limited metabolism through the cytochrome P450 system. This unique pharmacokinetic profile may provide clinicians with a new era of managing thromboembolic disorders. Two of these agents, dabigatran and rivaroxaban, have been approved by the US Food and Drug Administration (FDA) for stroke prevention in patients with nonvalvular atrial fibrillation (AF); in addition, rivaroxaban can be used in the prevention of venous thromboembolism (VTE) in total hip and knee arthroplasty during the acute and extended periods of risk. However, the challenge for hospital formularies will be the appropriate use and management of these new medications as they become integrated into outpatient care. In order to better understand the issues that pharmacy and therapeutics committees will encounter, a review of the 2 FDA-approved oral anticoagulants will be evaluated.

Topics: Administration, Oral; Anticoagulants; Antithrombins; Benzamides; Benzimidazoles; beta-Alanine; Dabigatran; Formularies, Hospital as Topic; Humans; Morpholines; Pennsylvania; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Thiophenes; Warfarin

Topics: Acenocoumarol; Anticoagulants; Benzamides; Benzimidazoles; beta-Alanine; Dabigatran; Heparin; Humans; Morpholines; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Stroke; Thiazoles; Thiophenes; Thromboembolism; Thrombosis; Warfarin

Interpatient variability in the safety and efficacy of oral anticoagulation with warfarin presents several challenges to clinicians, thus underscoring the emergent need for new orally available anticoagulants with predictable pharmacokinetic and pharmacodynamic profiles and ability to target circulating clotting factors. Seven compounds including rivaroxaban, apixaban, betrixaban, and eribaxaban are orally available direct inhibitors of activated factor X currently in development for the prevention and treatment of venous thromboembolism and for thromboprophylaxis in patients with atrial fibrillation or following an acute coronary syndrome. At doses used in phase 2 and 3 clinical trials, rivaroxaban and apixaban demonstrated a predictable onset of effect, maximal plasma concentration, and half-life that was unaffected by age, renal, or hepatic disease. In clinical trials for the treatment and prevention of venous thromboembolism, rivaroxaban and apixaban produced equivalent or superior reductions in the development or progression of venous thromboembolism compared with either low molecular weight heparin or warfarin. Trials comparing the efficacy of rivaroxaban or apixaban to standard therapy for stroke prophylaxis in patients with atrial fibrillation are in process. Rivaroxaban, the sentinel compound in this class, is already approved in the European Union and Canada. It is likely to be approved for use in the United States in 2010.

Topics: Administration, Oral; Anticoagulants; Atrial Fibrillation; Benzamides; Blood Coagulation Disorders; Clinical Trials as Topic; Factor Xa Inhibitors; Heparin, Low-Molecular-Weight; Humans; Morpholines; Pyrazoles; Pyridines; Pyridones; Rivaroxaban; Stroke; Thiophenes; Thromboembolism; Warfarin