betrixaban and Hemorrhage

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

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

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

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

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

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

Acutely ill medical patients with cancer are at increased risk of venous thromboembolism (VTE). Thromboprophylaxis is recommended in the presence of cancer, but its safety is not known. The aim of this study was to assess the efficacy and safety of extended prophylaxis with betrixaban in cancer patients enrolled in the APEX trial. APEX was a randomized, double-blind trial comparing oral betrixaban 80 mg qd administered for 35-42 days with subcutaneous enoxaparin 40 mg qd administered for 10 ± 4 days. Patients with acute medical illness and a history of cancer or active cancer were eligible for inclusion. Primary efficacy outcome was VTE (composite of symptomatic VTE and asymptomatic proximal deep vein thrombosis); primary safety outcome was major bleeding. Of 7513 patients enrolled in the APEX trial, 959 patients (12.8%), 499 randomized to betrixaban and 460 to enoxaparin, had cancer. The primary efficacy outcome occurred in 5.7% of cancer patients treated with betrixaban and in 6.2% treated with enoxaparin (p = 0.95). No significant interaction according to the presence or absence of cancer was observed (p = 0.36). Major bleeding events occurred in 0.8% of patients in the betrixaban group and in 0% in the enoxaparin group (p = 0.13), with no significant interaction (p = 0.07). The composite of major and clinically relevant non-major bleeds was similar between the two groups (2.9% and 2.0%, respectively, RR 1.43, 95% CI 0.63-3.27). Betrixaban was similarly effective in the reduction of VTE among subjects with and without cancer. The incidence of major bleeding was similarly low.

Topics: Acute Disease; Aged; Aged, 80 and over; Benzamides; Critical Illness; Double-Blind Method; Drug Administration Schedule; Factor Xa Inhibitors; Female; Hemorrhage; Humans; Male; Neoplasms; Post-Exposure Prophylaxis; Pyridines; Venous Thrombosis

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

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

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

Patients with atrial fibrillation (AF) are at increased risk of stroke. Betrixaban is a novel oral factor Xa inhibitor administered once daily, mostly excreted unchanged in the bile and with low (17%) renal excretion.. Patients with AF and more than one risk factor for stroke were randomized to one of three blinded doses of betrixaban (40, 60, or 80 mg once daily) or unblinded warfarin, adjusted to an international normalized ratio of 2.0-3.0. The primary outcome was major or clinically relevant non-major bleeding. The mean follow-up was 147 days. Among 508 patients randomized, the mean CHADS2 score was 2.2; 87% of patients had previously received vitamin K antagonist therapy. The time in therapeutic range on warfarin was 63.4%. There were one, five, five, and seven patients with a primary outcome on betrixaban 40, 60, 80 mg daily, or warfarin, respectively. The rate of the primary outcome was lowest on betrixaban 40 mg (hazard ratio compared with warfarin = 0.14, exact stratified log-rank P-value 0.04, unadjusted for multiple testing). Rates of the primary outcome with betrixaban 60 or 80 mg were more similar to those of wafarin. Two ischaemic strokes occurred, one each on betrixaban 60 and 80 mg daily. There were two vascular deaths, one each on betrixaban 40 mg and warfarin. Betrixaban was associated with higher rates of diarrhoea than warfarin.. Betrixaban was well tolerated and had similar or lower rates of bleeding compared with well-controlled warfarin in patients with AF at risk for stroke.

Topics: Aged; Anticoagulants; Atrial Fibrillation; Benzamides; Dose-Response Relationship, Drug; Female; Fibrin Fibrinogen Degradation Products; Hemorrhage; Humans; Male; Pyridines; Stroke; Treatment Outcome; Warfarin

Coagulation factor Xa (fXa) is a particularly attractive target for the development of effective and safe anticoagulants. In this study, novel 2,3-dihydroquinazolin-4(1H)-one derivatives were designed as potential fXa inhibitors based on anthranilamide structure which has been reported in our previous research. The experimental data showed that most of the designed compounds exhibited significant in vitro potency against fXa. Among them, compound 8e displayed the strongest potency against fXa with the IC

Topics: Animals; Drug Design; Factor Xa; Factor Xa Inhibitors; Hemorrhage; Humans; Molecular Docking Simulation; Quinazolinones; Rats; 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