Benefit–risk profile of non-vitamin K antagonist oral anticoagulants in the management of venous thromboembolism

SummaryThe prevention and treatment of venous thromboembolism (VTE) remains a clinical challenge, primarily owing to drawbacks associated with the use of heparins and vitamin K antagonists (VKAs). These and other factors, including a growing elderly population, mean that VTE presents a continuing burden to patients and physicians. Anticoagulant therapy is a fundamental approach for VTE management. Non- VKA oral anticoagulants, including the factor Xa inhibitors apixaban, edoxaban and rivaroxaban, and the thrombin inhibitor dabigatran, have been studied in phase III trials across a spectrum of thromboembolic disorders. These agents offer simplified care, with similar or improved efficacy and safety outcomes compared with heparins and vitamin K antagonists. There are several factors a physician must consider when prescribing an anticoagulant. An important consideration with all anticoagulant use is bleeding risk, especially in high-risk groups such as the elderly or those with renal impairment or cancer. In orthopaedic patients, other risks include a need for surgical revision or blood transfusion, or wound complications. Therefore, the clinical benefits of an anticoagulant should ideally be balanced with any risks associated with the therapy. Quantitative benefit–risk assessments are lacking, and owing to differences in trial design the non-VKA oral anticoagulants cannot be compared directly. Based on trial and “reallife” data, this review will summarise the clinical data for the non-VKA oral anticoagulants in the prevention and treatment of VTE, focusing on the balance between the benefits and risks of anticoagulation with these drugs, and their potential impact on VTE management.

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RE-COVERY DVT/PE: Rationale and design of a prospective observational study of acute venous thromboembolism with a focus on dabigatran etexilate

Thrombosis and Haemostasis ◽

10.1160/th16-07-0566 ◽

2017 ◽

Vol 117 (02) ◽

pp. 415-421 ◽

Cited By ~ 6

Author(s):

Walter Ageno ◽

Ivan B. Casella ◽

Chee Kok Han ◽

Gary E. Raskob ◽

Sebastian Schellong ◽

...

Keyword(s):

Venous Thromboembolism ◽

Vitamin K ◽

Large Scale ◽

Vitamin K Antagonists ◽

Phase 1 ◽

Dabigatran Etexilate ◽

Oral Anticoagulants ◽

Phase Iii ◽

Real World Data ◽

Phase Iii Studies

SummaryThe therapeutic management of venous thromboembolism (VTE) is rapidly evolving. Following the positive results of pivotal large-scale randomised trials, the non-vitamin K antagonist oral anticoagulants (NOACs) represent an important alternative to standard anticoagulation. In phase III studies, dabigatran was as effective as, and significantly safer than warfarin. Additional information on real-world data of dabigatran is now warranted. RE-COVERY DVT/PE is a multi-centre, international, observational (i. e. non-interventional) study enrolling patients with acute DVT and/or PE within 30 days after objective diagnosis. The study is designed with two phases. Phase 1 has a cross-sectional design, enrolling approximately 6000 patients independently of treatment choice, with the aim of providing a contemporary picture of the management of VTE worldwide. Phase 2 has a prospective cohort design, with follow-up of one year, enrolling 8000 patients treated with dabigatran or vitamin K antagonists (VKAs) with the aim of comparing their safety, defined by the occurrence of major bleeding, and effectiveness, defined by the occurrence of symptomatic recurrent VTE. RE-COVERY DVT/PE will complement both the results of other observational studies in this field and the results of phase III studies with dabigatran, in particular by assessing its clinical benefit in various patient subgroups treated in routine clinical practice.

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Meta-analysis comparing impact of age, sex and renal function on the efficacy and safety of new oral anticoagulants vs. vitamin K antagonists for the treatment of acute venous thromboembolisms

European Heart Journal ◽

10.1093/ehjci/ehaa946.2374 ◽

2020 ◽

Vol 41 (Supplement_2) ◽

Author(s):

J She ◽

B.Z Zhuo

Keyword(s):

Renal Function ◽

Venous Thromboembolism ◽

Creatinine Clearance ◽

Vitamin K ◽

Meta Analysis ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

Funding Source ◽

Efficacy And Safety ◽

Acute Venous Thromboembolism

Abstract Background New direct oral anticoagulants (NOACs), as a preferable treatment option for acute venous thromboembolism (VTE) have been recommended with practical advantages as compared to Vitamin K antagonists (VKAs) in clinical practice. Purpose In our study, we performed a meta-analysis to determine the efficacy and safety of NOACs vs. VKAs in patients with different age, sex and renal function for the treatment of VTE. Methods Electronic databases (accessed October 2019) were systematically searched to identify RCTs evaluating apixaban, dabigatran, edoxaban, and rivaroxaban versus VKAs for the treatment of acute venous thromboembolism. Results NOACs was associated with a borderline higher efficacy in female (OR 0.79, 95% CI 0.62–1.02), and a significantly higher efficacy in patients with age more than 75 (OR 0.51, 95% CI 0.32–0.80) and creatinine clearance less than 50 mL/min (OR 0.57, 95% CI 0.32–0.99). NOACs also show advantage in terms of major or clinically relevant non-major bleeding in male (OR 0.72, 95% CI 0.60–0.86), and patients with creatinine clearance more than 50 mL/min (OR 0.75, 95% CI 0.67–0.84). Conclusions NOACs have exhibited clinical preference among patients with acute VTE as compared to VKA with significantly decreased thrombosis events and lower bleeding complications, especially in patients with age more than 75 and creatinine clearance less than 50 mL/min. Funding Acknowledgement Type of funding source: Public Institution(s). Main funding source(s): This study was supported by the National Natural Science Foundation of China (81800390) and the Natural Science Foundation of Shaanxi province (2018KW067).

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Prevention and treatment of venous thromboembolism in patients with cancer

Hematology ◽

10.1182/asheducation-2014.1.312 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 312-317 ◽

Cited By ~ 4

Author(s):

Agnes Y.Y. Lee

Keyword(s):

Venous Thromboembolism ◽

Vitamin K ◽

Vitamin K Antagonists ◽

Hospital Setting ◽

Chemotherapeutic Agents ◽

Ambulatory Setting ◽

Individual Risk ◽

Patients With Cancer ◽

Gastrointestinal Problems ◽

Prevention And Treatment

Abstract Robust evidence remains scarce in guiding best practice in the prevention and treatment of venous thromboembolism in patients living with cancer. Recommendations from major consensus guidelines are largely based on extrapolated data from trials performed mostly in noncancer patients, observational studies and registries, studies using surrogate outcomes, and underpowered randomized controlled trials. Nonetheless, a personalized approach based on individual risk assessment is uniformly recommended for inpatient and outpatient thromboprophylaxis and there is consensus that anticoagulant prophylaxis is warranted in selected patients with a high risk of thrombosis. Prediction tools for estimating the risk of thrombosis in the hospital setting have not been validated, but the use of prophylaxis in the ambulatory setting in those with a high Khorana score is under active investigation. Symptomatic and incidental thrombosis should be treated with anticoagulant therapy, but little is known about the optimal duration. Pharmacologic options for prophylaxis and treatment are still restricted to unfractionated heparin, low molecular weight heparin, and vitamin K antagonists because there is currently insufficient evidence to support the use of target-specific, non-vitamin K-antagonist oral anticoagulants. Although these agents offer practical advantages over traditional anticoagulants, potential drug interaction with chemotherapeutic agents, gastrointestinal problems, hepatic and renal impairment, and the lack of rapid reversal agents are important limitations that may reduce the efficacy and safety of these drugs in patients with active cancer. Clinicians and patients are encouraged to participate in clinical trials to advance the care of patients with cancer-associated thrombosis.

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The Severity of Intracranial Hemorrhages Measured by Free Hemoglobin in the Brain Depends on the Anticoagulant Class: Experimental Data

Stroke Research and Treatment ◽

10.1155/2017/6516401 ◽

2017 ◽

Vol 2017 ◽

pp. 1-4 ◽

Cited By ~ 1

Author(s):

Kyle M. Ware ◽

Douglas L. Feinstein ◽

Israel Rubinstein ◽

Prudhvi Battula ◽

Jose Otero ◽

...

Keyword(s):

Vitamin K ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Factor Xa ◽

Hemoglobin Concentration ◽

Thrombin Inhibitor ◽

Free Hemoglobin ◽

Intracranial Hemorrhages ◽

The Brain

Background and Purpose. Anticoagulant therapy is broadly used to prevent thromboembolic events. Intracranial hemorrhages are serious complications of anticoagulation, especially with warfarin. Direct oral anticoagulants reduce but do not eliminate the risk of intracranial hemorrhages. The aim of this study is to determine the degree of intracranial hemorrhage after application of anticoagulants without additional triggers. Methods. Rats were treated with different anticoagulant classes (vitamin K antagonists, heparin, direct thrombin inhibitor, and factor Xa inhibitor). Brain hemorrhages were assessed by the free hemoglobin concentration in the brain parenchyma. Results. Vitamin K antagonists (warfarin and brodifacoum) significantly increased free hemoglobin in the brain. Among direct oral anticoagulants, thrombin inhibitor dabigatran also significantly increased free hemoglobin in the brain, whereas treatment with factor Xa inhibitor rivaroxaban did not have significant effect on the free hemoglobin concentration. Conclusions. Our data indicates that the severity of brain hemorrhages depends on the anticoagulant class and it is more pronounced with vitamin K antagonists.

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Update on Edoxaban for the Prevention and Treatment of Thromboembolism: Clinical Applications Based on Current Evidence

Advances in Hematology ◽

10.1155/2015/920361 ◽

2015 ◽

Vol 2015 ◽

pp. 1-19 ◽

Cited By ~ 5

Author(s):

Ali Zalpour ◽

Thein Hlaing Oo

Keyword(s):

Vitamin K Antagonists ◽

Dabigatran Etexilate ◽

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Factor Xa ◽

Coagulation Factors ◽

Current Evidence ◽

Thrombin Inhibitor ◽

Prevention And Treatment ◽

Financial Impacts

Vitamin K antagonists (VKA) and heparins have been utilized for the prevention and treatment of thromboembolism (arterial and venous) for decades. Targeting and inhibiting specific coagulation factors have led to new discoveries in the pharmacotherapy of thromboembolism management. These targeted anticoagulants are known as direct oral anticoagulants (DOACs). Two pharmacologically distinct classes of targeted agents are dabigatran etexilate (Direct Thrombin Inhibitor (DTI)) and rivaroxaban, apixaban, and edoxaban (direct oral factor Xa inhibitors (OFXaIs)). Emerging evidence from the clinical trials has shown that DOACs are noninferior to VKA or low-molecular-weight heparins in the prevention and treatment of thromboembolism. This review examines the role of edoxaban, a recently approved OFXaI, in the prevention and treatment of thromboembolism based on the available published literature. The management of edoxaban in the perioperative setting, reversibility in bleeding cases, its role in cancer patients, the relevance of drug-drug interactions, patient satisfaction, financial impacts, and patient education will be discussed.

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Non-vitamin K antagonist oral anticoagulants (NOACs) versus vitamin K antagonists (VKAs) in (morbidly) obese or low body weight patients with atrial fibrillation: a meta-analysis

EP Europace ◽

10.1093/europace/euab116.268 ◽

2021 ◽

Vol 23 (Supplement_3) ◽

Author(s):

M Grymonprez ◽

TL De Backer ◽

S Steurbaut ◽

K Boussery ◽

L Lahousse

Keyword(s):

Body Weight ◽

Cohort Studies ◽

Vitamin K ◽

Meta Analysis ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

Phase Iii ◽

Morbidly Obese ◽

Class Iii ◽

Observational Cohort

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – National budget only. Main funding source(s): Fund for Scientific Research Flanders (FWO) Background Oral anticoagulants are crucial for preventing systemic thromboembolism in atrial fibrillation (AF), with guidelines preferring non-vitamin K antagonist oral anticoagulants (NOACs) over vitamin K antagonists (VKAs) in the general AF population. However, as NOACs are administered in fixed doses, concerns of unintentional underdosing in morbidly obese patients and unintentional overdosing in underweight patients have emerged. Moreover, VKAs are still recommended in morbidly obese patients (body mass index (BMI) ≥40 kg/m², body weight >120 kg) due to lack of data for NOACs in these patients. Purpose A critical appraisal of the benefit-risk profile of NOACs in AF patients across the body weight spectrum. Methods After searching the Medline database, phase III randomized controlled trials (RCTs) and longitudinal observational cohort studies on the effectiveness and safety of NOACs versus VKAs in obese (BMI ≥30 kg/m²), and class III obese (BMI ≥40 kg/m²) non-valvular AF patients, and in low body weight (≤60 kg) AF patients during a mean/median follow-up of ≥6 months were included. The meta-analyses were performed using a random effects model with the Mantel-Haenszel method. Results A meta-analysis based on 4 phase III RCTS and 3 longitudinal observational cohort studies demonstrated that NOAC use in obese and class III obese AF patients was associated with significantly lower stroke/systemic embolism (stroke/SE) risks (RR 0.82, 95%CI [0.71-0.96]; and RR 0.75, 95%CI [0.64-0.87], respectively), similar to lower major bleeding risks (RR 0.83, 95%CI [0.69-1.00]; and RR 0.74, 95%CI [0.57-0.95], respectively), and similar mortality risks (RR 0.92, 95%CI [0.73-1.15]; and RR 1.17, 95%CI [0.83-1.64], respectively) as compared to VKAs. In AF patients ≤60 kg, significantly lower stroke/SE (RR 0.63, 95%CI [0.56-0.71]) and major bleeding risks (RR 0.71, 95%CI [0.62-0.80]), and similar mortality risks (RR 0.68, 95%CI [0.42-1.10]) were observed for NOAC- versus VKA-treated patients in a meta-analysis based on 4 phase III RCTs and 2 longitudinal observational cohort studies. Conclusions The benefit-risk profile of NOACs seems preserved in (morbidly) obese AF patients and patients with low body weight of ≤60 kg. However, more data are needed in underweight AF patients (BMI <18.5 kg/m²) and on differences between NOACs to further optimize management in these patient subgroups.

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The NOACs: clinical pharmacology

ESC CardioMed ◽

10.1093/med/9780198784906.003.0056 ◽

2018 ◽

pp. 268-272

Author(s):

Jeffrey Weitz

Keyword(s):

Atrial Fibrillation ◽

Vitamin K ◽

Active Site ◽

Randomized Clinical Trials ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

Factor Xa ◽

Vitamin K Antagonist ◽

Phase Iii ◽

High Affinity

The limitations of vitamin K antagonists prompted the development of new oral anticoagulants that could be administered in fixed doses without routine coagulation monitoring. Focusing on thrombin and factor Xa because of their prominent roles in coagulation, structure-based design led to the development of small molecules that bind to the active site pockets of these enzymes with high affinity and specificity. Four non-vitamin K antagonist oral anticoagulants are now licensed: dabigatran, which inhibits thrombin, and rivaroxaban, apixaban, and edoxaban, which inhibit factor Xa. In phase III randomized clinical trials that included over 100,000 patients these agents have proven to be at least as effective as vitamin K antagonists for prevention of stroke in patients with non-valvular atrial fibrillation and for treatment of venous thromboembolism, and to produce less bleeding, particularly less intracranial bleeding.

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Ten years of non-vitamin K antagonists oral anticoagulants for stroke prevention in atrial fibrillation: is warfarin obsolete?

European Heart Journal Supplements ◽

10.1093/eurheartj/suaa177 ◽

2020 ◽

Vol 22 (Supplement_O) ◽

pp. O28-O41

Author(s):

Matthias Hammwöhner ◽

Andreas Goette

Keyword(s):

Atrial Fibrillation ◽

Clinical Data ◽

Vitamin K ◽

Stroke Prevention ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

Study Data ◽

Phase Iii ◽

Clinical Settings ◽

Specific Patient

Abstract Currently, four non-vitamin K antagonists oral anticoagulants (NOACs) are available for stroke prevention in atrial fibrillation (AF). These have been in clinical use for up to 10 years now. Besides data of the initial phase III clinical trials, now clinical data, several sub-studies, meta-analyses, and studies in special clinical settings and specific patient populations are available. This review shall give an overview on the history of NOAC development, sum up study data and ‘real-world’ clinical data as well as discuss several special clinical settings like NOAC treatment in patients that require coronary artery stenting or cardioversion (CV). Furthermore, treatment considerations in special patient populations like patients with renal impairment, obesity, or patients requiring NOACs for secondary prevention are discussed. The significance of NOAC treatment will be discussed under consideration of the recently published 2020 ESC/EACTS Guidelines for the diagnosis and management of AF.

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Dabigatran after Short Heparin Anticoagulation for Acute Intermediate-Risk Pulmonary Embolism: Rationale and Design of the Single-Arm PEITHO-2 Study

Thrombosis and Haemostasis ◽

10.1160/th17-06-0434 ◽

2017 ◽

Vol 117 (12) ◽

pp. 2425-2434 ◽

Cited By ~ 4

Author(s):

Frederikus Klok ◽

Walter Ageno ◽

Stefano Barco ◽

Harald Binder ◽

Benjamin Brenner ◽

...

Keyword(s):

Pulmonary Embolism ◽

Venous Thromboembolism ◽

Oral Anticoagulants ◽

Direct Oral Anticoagulants ◽

Phase Iii ◽

Thrombin Inhibitor ◽

Intermediate Risk ◽

Safety Outcome ◽

Efficacy Outcome ◽

Heparin Anticoagulation

AbstractPatients with intermediate-risk pulmonary embolism (PE) may, depending on the method and cut-off values used for definition, account for up to 60% of all patients with PE and have an 8% or higher risk of short-term adverse outcome. Although four non-vitamin K-dependent direct oral anticoagulants (NOACs) have been approved for the treatment of venous thromboembolism, their safety and efficacy as well as the optimal anticoagulation regimen using these drugs have not been systematically investigated in intermediate-risk PE. Moreover, it remains unknown how many patients with intermediate-high-risk and intermediate-low-risk PE were included in most of the phase III NOAC trials. The ongoing Pulmonary Embolism International Thrombolysis 2 (PEITHO-2) study is a prospective, multicentre, multinational, single-arm trial investigating whether treatment of acute intermediate-risk PE with parenteral heparin anticoagulation over the first 72 hours, followed by the direct oral thrombin inhibitor dabigatran over 6 months, is effective and safe. The primary efficacy outcome is recurrent symptomatic venous thromboembolism or death related to PE within the first 6 months. The primary safety outcome is major bleeding as defined by the International Society on Thrombosis and Haemostasis. Secondary outcomes include all-cause mortality, the overall duration of hospital stay (index event and repeated hospitalizations) and the temporal pattern of recovery of right ventricular function over the 6-month follow-up period. By applying and evaluating a contemporary risk-tailored treatment strategy for acute PE, PEITHO-2 will implement the recommendations of current guidelines and contribute to their further evolution.

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Stroke Prevention in Atrial Fibrillation: Understanding the New Oral Anticoagulants Dabigatran, Rivaroxaban, and Apixaban

Thrombosis ◽

10.1155/2012/108983 ◽

2012 ◽

Vol 2012 ◽

pp. 1-10 ◽

Cited By ~ 8

Author(s):

Tan Ru San ◽

Mark Yan Yee Chan ◽

Teo Wee Siong ◽

Tang Kok Foo ◽

Ng Kheng Siang ◽

...

Keyword(s):

Atrial Fibrillation ◽

Stroke Prevention ◽

Primary Care Physicians ◽

Vitamin K Antagonists ◽

Oral Anticoagulants ◽

New Oral Anticoagulants ◽

Phase Iii ◽

Fixed Dose ◽

Thrombin Inhibitor ◽

Factor X

Unlike vitamin K antagonists (VKAs), the new oral anticoagulants (NOACs)—direct thrombin inhibitor, dabigatran, and direct activated factor X inhibitors, rivaroxaban, and apixaban—do not require routine INR monitoring. Compared to VKAs, they possess relatively rapid onset of action and short halflives, but vary in relative degrees of renal excretion as well as interaction with p-glycoprotein membrane transporters and liver cytochrome P450 metabolic enzymes. Recent completed phase III trials comparing NOACs with VKAs for stroke prevention in atrial fibrillation (AF)—the RE-LY, ROCKET AF, and ARISTOTLE trials—demonstrated at least noninferior efficacy, largely driven by significant reductions in haemorrhagic stroke. Major and nonmajor clinically relevant bleeding rates were acceptable compared to VKAs. Of note, the NOACs caused significantly less intracranial haemorrhagic events compared to VKAs, the mechanisms of which are not completely clear. With convenient fixed-dose administration, the NOACs facilitate anticoagulant management in AF in the community, which has hitherto been grossly underutilised. Guidelines should evolve towards simplicity in anticipation of greater use of NOACs among primary care physicians. At the same time, the need for caution with their use in patients with severely impaired renal function should be emphasised.

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