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Circulation Jan 2023Non-vitamin K oral anticoagulants have become the standard therapy for preventing stroke and ischemic thromboembolism in most patients with atrial fibrillation (AF). The... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Non-vitamin K oral anticoagulants have become the standard therapy for preventing stroke and ischemic thromboembolism in most patients with atrial fibrillation (AF). The effectiveness and safety of non-vitamin K oral anticoagulants in patients on hemodialysis is not well known.
METHODS
From June 2017 through May 2022, AXADIA-AFNET 8 (Compare Apixaban and Vitamin K Antagonists in Patients With Atrial Fibrillation and End-Stage Kidney Disease), an investigator-initiated PROBE (prospective randomized open blinded end point) outcome assessment trial, randomized patients with AF on chronic hemodialysis to either apixaban (2.5 mg BID) or the vitamin K antagonist (VKA) phenprocoumon (international normalized ratio, 2.0 to 3.0). The composite primary safety outcome was defined by a first event of major bleeding, clinically relevant nonmajor bleeding, or all-cause death. The primary efficacy outcome was a composite of ischemic stroke, all-cause death, myocardial infarction, and deep vein thrombosis or pulmonary embolism. Our hypothesis was that apixaban is noninferior to VKA.
RESULTS
Thirty-nine sites randomized 97 patients (30% women; mean age 75 years; mean CHADS-VASc [congestive heart failure, hypertension, age ≥75 years, diabetes, stroke or transient ischemic attack, vascular disease, age 65 to 74 years, female sex] score, 4.5; baseline characteristics balanced between groups): 48 to apixaban and 49 to VKA. The median follow-up time was 429 days (range, 37 to 1370) versus 506 days (range, 101 to 1379), respectively. Adherence to apixaban was >80% in 44 of 48 patients; the median time in therapeutic range on VKA was 50.7%. Composite primary safety outcome events occurred in 22 patients (45.8%) on apixaban and in 25 patients (51.0%) on VKA (hazard ratio, 0.93 [95% CI, 0.53-1.65]; =0.157). Composite primary efficacy outcome events occurred in 10 patients (20.8%) on apixaban and in 15 patients (30.6%) on VKA (=0.51; log rank). There were no significant differences regarding individual outcomes (all-cause mortality, 18.8% versus 24.5%; major bleeding, 10.4% versus 12.2%; and myocardial infarction, 4.2% versus 6.1%, respectively).
CONCLUSIONS
In this randomized trial comparing apixaban and VKA in patients with AF on hemodialysis with long follow-up, no differences were observed in safety or efficacy outcomes. Even on oral anticoagulation, patients with AF on hemodialysis remain at high risk of cardiovascular events. Larger randomized trials are needed to determine the optimal anticoagulation regimen for patients with AF on hemodialysis.
REGISTRATION
URL: https://www.
CLINICALTRIALS
gov; Unique identifier: NCT02933697.
Topics: Humans; Female; Aged; Male; Phenprocoumon; Atrial Fibrillation; Prospective Studies; Anticoagulants; Stroke; Hemorrhage; Pyridones; Renal Dialysis; Myocardial Infarction; Treatment Outcome
PubMed: 36335915
DOI: 10.1161/CIRCULATIONAHA.122.062779 -
The Lancet. Neurology May 2021Cervical artery dissection is a major cause of stroke in young people (aged <50 years). Historically, clinicians have preferred using oral anticoagulation with vitamin K... (Comparative Study)
Comparative Study Randomized Controlled Trial
BACKGROUND
Cervical artery dissection is a major cause of stroke in young people (aged <50 years). Historically, clinicians have preferred using oral anticoagulation with vitamin K antagonists for patients with cervical artery dissection, although some current guidelines-based on available evidence from mostly observational studies-suggest using aspirin. If proven to be non-inferior to vitamin K antagonists, aspirin might be preferable, due to its ease of use and lower cost. We aimed to test the non-inferiority of aspirin to vitamin K antagonists in patients with cervical artery dissection.
METHODS
We did a multicentre, randomised, open-label, non-inferiority trial in ten stroke centres across Switzerland, Germany, and Denmark. We randomly assigned (1:1) patients aged older than 18 years who had symptomatic, MRI-verified, cervical artery dissection within 2 weeks before enrolment, to receive either aspirin 300 mg once daily or a vitamin K antagonist (phenprocoumon, acenocoumarol, or warfarin; target international normalised ratio [INR] 2·0-3·0) for 90 days. Randomisation was computer-generated using an interactive web response system, with stratification according to participating site. Independent imaging core laboratory adjudicators were masked to treatment allocation, but investigators, patients, and clinical event adjudicators were aware of treatment allocation. The primary endpoint was a composite of clinical outcomes (stroke, major haemorrhage, or death) and MRI outcomes (new ischaemic or haemorrhagic brain lesions) in the per-protocol population, assessed at 14 days (clinical and MRI outcomes) and 90 days (clinical outcomes only) after commencing treatment. Non-inferiority of aspirin would be shown if the upper limit of the two-sided 95% CI of the absolute risk difference between groups was less than 12% (non-inferiority margin). This trial is registered with ClinicalTrials.gov, NCT02046460.
FINDINGS
Between Sept 11, 2013, and Dec 21, 2018, we enrolled 194 patients; 100 (52%) were assigned to the aspirin group and 94 (48%) were assigned to the vitamin K antagonist group. The per-protocol population included 173 patients; 91 (53%) in the aspirin group and 82 (47%) in the vitamin K antagonist group. The primary endpoint occurred in 21 (23%) of 91 patients in the aspirin group and in 12 (15%) of 82 patients in the vitamin K antagonist group (absolute difference 8% [95% CI -4 to 21], non-inferiority p=0·55). Thus, non-inferiority of aspirin was not shown. Seven patients (8%) in the aspirin group and none in the vitamin K antagonist group had ischaemic strokes. One patient (1%) in the vitamin K antagonist group and none in the aspirin group had major extracranial haemorrhage. There were no deaths. Subclinical MRI outcomes were recorded in 14 patients (15%) in the aspirin group and in 11 patients (13%) in the vitamin K antagonist group. There were 19 adverse events in the aspirin group, and 26 in the vitamin K antagonist group.
INTERPRETATION
Our findings did not show that aspirin was non-inferior to vitamin K antagonists in the treatment of cervical artery dissection.
FUNDING
Swiss National Science Foundation, Swiss Heart Foundation, Stroke Funds Basel, University Hospital Basel, University of Basel, Academic Society Basel.
Topics: Acenocoumarol; Adult; Anticoagulants; Aspirin; Carotid Artery, Internal, Dissection; Denmark; Female; Germany; Humans; Male; Middle Aged; Phenprocoumon; Platelet Aggregation Inhibitors; Stroke; Switzerland; Vertebral Artery Dissection; Warfarin
PubMed: 33765420
DOI: 10.1016/S1474-4422(21)00044-2 -
Journal of Thrombosis and Haemostasis :... Jun 2015The utility of using genetic information to guide warfarin dosing has remained unclear based on prior observational studies and small clinical trials. Two larger trials... (Review)
Review
The utility of using genetic information to guide warfarin dosing has remained unclear based on prior observational studies and small clinical trials. Two larger trials of warfarin and one of the acenocoumarol and phenprocoumon have recently been published. The COAG trial addressed the incremental benefit of adding genetic information to clinical information and demonstrated no benefit from the pharmacogenetic-based dosing strategy on the primary outcome. The EU-PACT UK trial compared an algorithm approach using genetic and clinical information to one that used a relatively fixed starting dose. The pharmacogenetic-based algorithms improved the primary outcome. The study of acenocoumarol and phenprocoumon compared a pharmacogenetic with a clinical algorithm and demonstrated no benefit on the primary outcome. The evidence to date does not support an incremental benefit of adding genetic information to clinical information on anticoagulation control. However, compared with fixed dosing, a pharmacogenetic algorithm can improve anticoagulation control.
Topics: Algorithms; Anticoagulants; Blood Coagulation; Blood Coagulation Tests; Drug Dosage Calculations; Drug Monitoring; Genotype; Humans; Pharmacogenetics; Phenotype; Precision Medicine; Predictive Value of Tests; Treatment Outcome; Warfarin
PubMed: 26149035
DOI: 10.1111/jth.12978 -
Thrombosis Journal Mar 2021Determination of anticoagulant therapy is of pronounced interest in emergency situations. However, routine tests do not provide sufficient insight. This study was...
BACKGROUND
Determination of anticoagulant therapy is of pronounced interest in emergency situations. However, routine tests do not provide sufficient insight. This study was performed to investigate the impact of anticoagulants on the results of viscoelastometric assays using the ClotPro device.
METHODS
This prospective, observational study was conducted in patients receiving dabigatran, factor Xa (FXa)-inhibitors, phenprocoumon, low molecular weight heparin (LMWH) or unfractionated heparin (UFH) (local ethics committee approval number: 17-525-4). Healthy volunteers served as controls. Viscoelastometric assays were performed, including the extrinsic test (EX-test), intrinsic test (IN-test) Russel's viper venom test (RVV-test), ecarin test (ECA-test), and the tissue plasminogen activator test (TPA-test).
RESULTS
70 patients and 10 healthy volunteers were recruited. Clotting time in the EX-test (CT) was significantly prolonged versus controls by dabigatran, FXa inhibitors and phenprocoumon. CT was prolonged by dabigatran, FXa inhibitors and UFH. Dabigatran, FXa inhibitors and UFH significantly prolonged CT in comparison with controls (median 200, 207 and 289 vs 63 s, respectively; all p < 0.0005). Only dabigatran elicited a significant increase in CT compared to controls (median 307 vs 73 s; p < 0.0001). CT correlated strongly with dabigatran plasma concentration (measured by anti-IIa activity; r = 0.9970; p < 0.0001) and provided 100% sensitivity and 100% specificity for detecting dabigatran. Plasma concentrations (anti-XA activity) of FXa inhibitors correlated with CT (r = 0.7998; p < 0.0001), and CT provided 83% sensitivity and 64% specificity for detecting FXa inhibitors.
CONCLUSIONS
In emergency situations, ClotPro viscoelastometric assessment of whole-blood samples may help towards determining the presence and type of anticoagulant class that a patient is taking.
TRIAL REGISTRATION
German clinical trials database ID: DRKS00015302 .
PubMed: 33726769
DOI: 10.1186/s12959-021-00267-w -
European Journal of Clinical... Apr 2011The anticoagulation response to vitamin K antagonists is characterised by high inter-individual variability. The impact of single nucleotide polymorphisms (SNPs) in... (Clinical Trial)
Clinical Trial
PURPOSE
The anticoagulation response to vitamin K antagonists is characterised by high inter-individual variability. The impact of single nucleotide polymorphisms (SNPs) in several genes of enzymes involved in the vitamin K cycle on phenprocoumon dose variability and phenprocoumon plasma concentrations is still under investigation.
METHODS
We assessed the influence of VKORC1 c.-1639G>A, CYP2C9*2, CYP2C9*3, CYP4F2 c.1297G>A, CALU c.*4A>G, EPHX1 c.337T>C, GGCX c.214+597G>A, F7 c.-402G>A, F7 c.-401G>T, PROC c.-228C>T and PROC c.-215G>A along with clinical and demographic parameters on steady-state phenprocoumon therapy in 75 patients. A prediction model was developed for total phenprocoumon plasma concentrations and daily phenprocoumon doses required for therapeutic anticoagulation.
RESULTS
The VKORC1 c.-1639 genotype was the main predictor of the phenprocoumon daily dose (adjusted R(2) = 37.6%) and the total phenprocoumon concentration (adjusted R(2) = 38.3%). CYP2C9 affected the phenprocoumon concentration, but not the dose requirements. SNPs in the other genes of the vitamin K cycle, concomitant medication, nicotine use and alcohol consumption did not predict phenprocoumon concentrations and phenprocoumon dose requirements in a multiple linear regression model. Phenprocoumon concentrations were predicted by VKORC1 c.-1639, CYP2C9 genotype, age and BMI. The final prediction model for the daily phenprocoumon dose requirements comprised VKORC1 c.-1639 genotype, age and height accounting for 48.6% of the inter-individual variability.
CONCLUSIONS
A rough prediction of phenprocoumon maintenance doses can be achieved by a limited set of parameters (VKORC1, age, height). The investigated SNPs in CYP4F2, CALU, EPHX1, GGCX, F7, and PROC did not improve the predictive value of a pharmacogenetic-based dosing equation for phenprocoumon.
Topics: Adult; Aged; Aged, 80 and over; Algorithms; Anticoagulants; Blood Coagulation Factors; Drug Dosage Calculations; Female; Humans; Middle Aged; Pharmacogenetics; Phenprocoumon; Polymorphism, Single Nucleotide; Vitamin K
PubMed: 21110013
DOI: 10.1007/s00228-010-0950-y -
Deutsches Arzteblatt International Aug 2012Drug interactions can have desired, reduced or unwanted effects. The probability of interactions increases with the number of drugs taken. The high rate of prescribed... (Review)
Review
BACKGROUND
Drug interactions can have desired, reduced or unwanted effects. The probability of interactions increases with the number of drugs taken. The high rate of prescribed drugs in elderly patients (65-year-old patients take an average of 5 drugs) increases the likelihood of drug interactions and thus the risk that drugs themselves can be the cause of hospitalization. According to meta-analyses, up to 7% of hospitalizations are drug-related.
METHODS
Selective literature review.
RESULTS
Drug interactions occur on pharmacodynamic and pharmacokinetic levels. Examples of pharmacodynamic interactions are simultaneous administration of a NSAID and phenprocoumon (additive interaction), or of aspirin and ibuprofen (antagonistic interaction). Pharmacokinetic interactions occur at the levels of absorption (e.g., levothyroxine and neutralizing antacids), elimination (e.g., digoxin and macrolides), and metabolism, as in the competition for cytochrome P450 enzymes (e.g., SSRIs and certain beta-blockers).
CONCLUSION
The systematic knowledge of drug interaction, in particular on the level of absorption, elimination, transport and drug metabolism may help to prevent adverse effects. Predicting pharmacodynamic interactions often demands a deeper understanding of the mechanisms of effect. Electronic prescribing systems are helpful.
Topics: Drug Interactions; Drug-Related Side Effects and Adverse Reactions; Humans; Prevalence
PubMed: 23152742
DOI: 10.3238/arztebl.2012.0546 -
Human Genomics and Proteomics : HGP Sep 2010Warfarin, acenocoumarol, and phenprocoumon are among the major anticoagulant drugs worldwide. Because of their low therapeutic index and serious adverse reactions...
Warfarin, acenocoumarol, and phenprocoumon are among the major anticoagulant drugs worldwide. Because of their low therapeutic index and serious adverse reactions (ADRs), their wide use, and their varying kinetics and pharmacogenetic dependence, it is of great importance to explore further possibilities to forecast the dose beyond conventional INR measurements. Here, we describe particulars of the relative pharmacogenetic influence on the kinetics of these agents, the population distribution of genetics risk groups, and novel data on clinical features with influence on dose requirement and ADR risk. The usefulness of genetic information prior to and soon after start of therapy is also discussed. The current renewed focus on these issues is caused not only because of new genetic knowledge and genotyping facilities but also because of the high rate of serious ADRs. Application of these measures in the care of patients with anticoagulant therapy is important awaiting new therapeutic principles to be introduced, which may take long time still.
PubMed: 20981234
DOI: 10.4061/2010/754919 -
British Journal of Clinical Pharmacology Apr 2014Coumarin derivatives, such as warfarin, acenocoumarol and phenprocoumon are frequently prescribed oral anticoagulants to treat and prevent thromboembolism. Because there... (Review)
Review
Coumarin derivatives, such as warfarin, acenocoumarol and phenprocoumon are frequently prescribed oral anticoagulants to treat and prevent thromboembolism. Because there is a large inter-individual and intra-individual variability in dose-response and a small therapeutic window, treatment with coumarin derivatives is challenging. Certain polymorphisms in CYP2C9 and VKORC1 are associated with lower dose requirements and a higher risk of bleeding. In this review we describe the use of different coumarin derivatives, pharmacokinetic characteristics of these drugs and differences amongst the coumarins. We also describe the current clinical challenges and the role of pharmacogenetic factors. These genetic factors are used to develop dosing algorithms and can be used to predict the right coumarin dose. The effectiveness of this new dosing strategy is currently being investigated in clinical trials.
Topics: Acenocoumarol; Algorithms; Anticoagulants; Clinical Trials as Topic; Cost-Benefit Analysis; Cytochrome P-450 CYP2C9; Drug Dosage Calculations; Genotype; Humans; Pharmacogenetics; Phenprocoumon; Vitamin K Epoxide Reductases; Warfarin
PubMed: 23919835
DOI: 10.1111/bcp.12220 -
British Journal of Clinical Pharmacology May 2019
Topics: Acenocoumarol; Adult; Aged; Aged, 80 and over; Anticoagulants; Antitussive Agents; Cough; Drug Interactions; Female; Hemorrhage; Humans; International Normalized Ratio; Male; Middle Aged; Netherlands; Nonprescription Drugs; Noscapine; Phenprocoumon; Thromboembolism
PubMed: 30809820
DOI: 10.1111/bcp.13887