Quantitative Benefit-Risk Evaluation of Rivaroxaban in Patients After Peripheral Arterial Revascularization: The VOYAGER PAD Trial.

BACKGROUND: The VOYAGER PAD (Efficacy and Safety of Rivaroxaban in Reducing the Risk of Major Thrombotic Vascular Events in Subjects With Symptomatic Peripheral Artery Disease Undergoing Peripheral Revascularization Procedures of the Lower Extremities) trial compared rivaroxaban (2.5 mg twice a day) plus aspirin with aspirin alone in patients with symptomatic peripheral artery disease requiring endovascular or surgical limb revascularization, with 50% receiving clopidogrel background therapy. The New Drug Indication application includes benefit-risk assessments using clinical judgment to balance benefits against risks. During its review, the US Food and Drug Administration requested additional quantitative benefit-risk analyses with formal weighting approaches. METHODS AND RESULTS: Benefits and risks were assessed using rate differences between treatment groups (unweighted analysis). To account for clinical importance of the end points, a multi-criteria decision analysis was conducted using health state utility values as weights. Monte Carlo simulations incorporated statistical uncertainties of the event rates and utility weights. Intent-to-treat and on-treatment analyses were conducted. For unweighted intent-to-treat analyses, rivaroxaban plus aspirin would result in 120 (95% CI, -208 to -32) fewer events of the primary composite end point (per 10 000 patient-years) compared with aspirin alone. Rivaroxaban caused an excess of 40 (95% CI, 8-72) Thrombolysis in Myocardial Infarction major bleeding events, which was largely driven by nonfatal, nonintracranial hemorrhage Thrombolysis in Myocardial Infarction major bleeding events. For weighted analyses, rivaroxaban resulted in the utility equivalent of 13.7 (95% CI, -85.3 to 52.6) and 68.1 (95% CI, 7.9-135.7) fewer deaths per 10 000 patient-years (intent-to-treat and on-treatment, respectively), corresponding to probabilities of 64.4% and 98.7%, respectively, that benefits outweigh risks favoring rivaroxaban per Monte Carlo simulation. CONCLUSIONS: These analyses show a favorable benefit-risk profile of rivaroxaban therapy in the VOYAGER PAD trial, with findings generally consistent between the unweighted and weighted approaches.

Toward Genetic Testing of Rivaroxaban? Insights from a Systematic Review on the Role of Genetic Polymorphism in Rivaroxaban Therapy.

BACKGROUND: Investigations into the rivaroxaban response from the perspective of genetic variation have been relatively recent and wide in scope, whereas there is no consensus on the necessity of genetic testing of rivaroxaban. Thus, this systematic review aims to thoroughly evaluate the relationship between genetic polymorphisms and rivaroxaban outcomes. METHODS: The PubMed, Embase, Cochrane Central Register of Controlled Trials (CENTRAL), and Chinese databases were searched to 23 October 2022. We included cohort studies reporting the pharmacogenetic correlation of rivaroxaban. Outcomes measured included efficacy (all-cause mortality, thromboembolic events and coagulation-related tests), safety (major bleeding, clinically relevant non-major bleeding [CRNMB] and any hemorrhage), and pharmacokinetic outcomes. A narrative synthesis was performed to summarize findings from individual studies according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses and the reporting guideline for Synthesis Without Meta-Analysis. RESULTS: A total of 12 studies published between 2019 and 2022 involving 1364 patients were included. Ten, one, and six studies focused on the ABCB1, ABCG2, and CYP gene polymorphisms, respectively. Pharmacokinetic outcomes accounted for the majority of the outcomes reported (n = 11), followed by efficacy (n = 5) [including prothrombin time (PT) or international normalized ratio (n = 3), platelet inhibition rate (PIR) or platelet reactivity units (PRUs; n = 1), thromboembolic events (n = 1)], and safety (n = 5) [including major bleeding (n = 2), CRNMB (n = 2), any hemorrhage (n = 1)]. For ABCB1 gene polymorphism, the relationship between PT and ABCB1 rs1045642 was inconsistent across studies, however there was no pharmacogenetic relationship with other efficacy outcomes. Safety associations were found in ABCB1 rs4148738 and major bleeding, ABCB1 rs4148738 and CRNMB, ABCB1 rs1045642 and CRNMB, and ABCB1 rs2032582 and hemorrhage. Pharmacokinetic results were inconsistent among studies. For ABCG2 gene polymorphism, no correlation was observed between ABCG2 rs2231142 and dose-adjusted trough concentration (Cmin/D). For CYP gene polymorphisms, PIR or PRUs have a relationship with CYP2C19 rs12248560, however bleeding or pharmacokinetic effects did not show similar results. CONCLUSIONS: Currently available data are insufficient to confirm the relationship between clinical or pharmacokinetic outcomes of rivaroxaban and gene polymorphisms. Proactive strategies are advised as a priority in clinical practice rather than detection of SNP genotyping. CLINICAL TRIALS REGISTRATION: PROSPERO registration number CRD42022347907.

Perioperative Treatment with Rivaroxaban and Dabigatran on Changes of Coagulation and Platelet Activation Biomarkers following Left Atrial Appendage Closure.

Insufficient data exist regarding the investigation of the impact of novel oral anticoagulants (NOACs) on coagulation activation biomarkers in the context of left atrial appendage closure (LAAC) and device-related thrombosis (DRT). The study was designed to investigate the changes and presence of coagulation activation biomarkers between different antithrombotic strategies following LAAC. A total of 120 nonvalvular atrial fibrillation patients intolerant of long-term anticoagulants, who underwent successful WATCHMAN closure implantation, were enrolled (rivaroxaban, n = 82; dabigatran, n = 38). Blood samples were obtained from left atrium (LA) and left atrial appendage (LAA) during the operation and fasting blood samples on the same day of LAAC and 45 days after discharge. The biochemical indicators, thrombin-antithrombin complex (TAT), soluble P-selectin (sP-selectin), von Willebrand factor (vWF), and CD40 ligand (CD40L), were measured by enzyme-linked immunosorbent assay. The primary endpoints of this study were the efficacy and safety characteristics of different antithrombotic strategies, including DRT incidence, stroke or transient ischemic attack, systemic embolism, and clinical major and nonmajor bleeding complications during the follow-up of 180 days. The results revealed that TAT, vWF, sP-selectin, and CD40L levels in vein were significantly reduced by 2.4% (p = 0.043), 5.0% (p < 0.001), 8.7% (p < 0.001), and 2.5% (p = 0.043) from their baseline levels after rivaroxaban treatment. Conversely, no significant changes were detected in the dabigatran group. Furthermore, the plasma levels of platelet activation biomarkers (CD40L and sP-selectin) in both LA and LAA groups were significantly lower after anticoagulation with rivaroxaban, as compared to dabigatran treatment (CD40L: 554.62 ± 155.54 vs. 445.02 ± 130.04 for LA p = 0.0013, 578.51 ± 156.28 vs. 480.13 ± 164.37 for LAA p = 0.0052; sP-selectin: 2849.07 ± 846.69 vs. 2225.54 ± 799.96 for LA p = 0.0105, 2915.52 ± 1402.40 vs. 2203.41 ± 1061.67 for LAA p = 0.0022). Notably, the present study suggests that rivaroxaban may be more effective in the prevention of DRT for patients undergoing LAAC.

Real-world experience of direct oral anticoagulant use in a single pediatric center.

BACKGROUND: Pediatric venous thromboembolism has increased by 130%-200%, specifically in hospitalized children, and direct oral anticoagulants (DOACs) offer several therapeutic advantages. METHODS: This study aims to evaluate the real-world epidemiological and outcome data from a retrospective review of pediatric patients treated with DOACs from January 1, 2013 to December 31, 2022. In this single-center, IRB-approved study, 65 patients were identified and analyzed using SPSS statistical software, and a descriptive statistical analysis was conducted. RESULTS: Of the 65 patients, 37% were on apixaban, 61.5% were on rivaroxaban, and 1.5% were on dabigatran. Per the 2023 ISTH outcome definitions, one (2%) patient had a major bleeding episode, six (9%) had clinically relevant non-major bleeding, three (5%) patients had patient-important heavy menstrual bleeding (HMB), and one (1.5%) patient had minor bleeding. Seven (19%) of 37 postmenarchal patients had evidence of HMB. Six (9.2%) patients had recurrent venous thromboembolism while on a DOAC (one was on apixaban, and five were on rivaroxaban) and were transitioned to other forms of anticoagulation. CONCLUSION: Thus, bleeding rates after DOAC therapy are comparable to previous DOAC trials, as well as other anticoagulants in pediatrics. HMB is an important outcome measure and should continue to be investigated. This study reports a higher rate of recurrent thrombosis (9.2%) compared to other trials. However, this observation may be attributed to patients who had ongoing risk factors, as well as a longer duration of study follow-up. Additional multicentered outcome studies evaluating DOAC use in children are needed to determine long-term recurrence and HMB risks.

Safety profile of rivaroxaban in first-time users treated for venous thromboembolism in four European countries.

BACKGROUND: The European rivaroxaban post-authorization safety study evaluated bleeding risk among patients initiated on rivaroxaban or vitamin K antagonists for the treatment and secondary prevention of venous thromboembolism in routine clinical practice. METHODS: Cohorts were created using electronic healthcare databases from the UK, the Netherlands, Germany and Sweden. Patients with a first prescription of rivaroxaban or vitamin K antagonist during the period from December 2011 (in the UK, January 2012) to December 2017 (in Germany, December 2016) for venous thromboembolism indication, with no record of atrial fibrillation or recent cancer history, were observed until the occurrence of each safety outcome (hospitalization for intracranial, gastrointestinal, urogenital or other bleeding), death or study end (December 2018; in Germany, December 2017). Crude incidence rates of each outcome per 100 person-years were computed. RESULTS: Overall, 44 737 rivaroxaban and 45 842 vitamin K antagonist patients were enrolled, mean age, 59.9-63.8 years. Incidence rates were similar between rivaroxaban and vitamin K antagonist users with some exceptions, including higher incidence rates for gastrointestinal bleeding in rivaroxaban users than in vitamin K antagonist users. Among rivaroxaban users, mortality and bleeding risk generally increased with age, renal impairment and diabetes. CONCLUSIONS: This study provides further data from routine clinical practice that broadly support safety profile of rivaroxaban for VTE indication and complement findings from previous randomized clinical trials.

The Effect of Levetiracetam Compared with Enzyme-Inducing Antiseizure Medications on Apixaban and Rivaroxaban Peak Plasma Concentrations.

BACKGROUND AND OBJECTIVE: Post-stroke epilepsy represents an important clinical challenge as it often requires both treatment with direct oral anticoagulants (DOACs) and antiseizure medications (ASMs). Levetiracetam (LEV), an ASM not known to induce metabolizing enzymes, has been suggested as a safer alternative to enzyme-inducing (EI)-ASMs in patients treated with DOACs; however, current clinical guidelines suggest caution when LEV is used with DOACs because of possible P-glycoprotein induction and competition (based on preclinical studies). We investigated whether LEV affects apixaban and rivaroxaban concentrations compared with two control groups: (a) patients treated with EI-ASMs and (b) patients not treated with any ASM. METHODS: In this retrospective observational study, we monitored apixaban and rivaroxaban peak plasma concentrations (Cmax) in 203 patients treated with LEV (n = 28) and with EI-ASM (n = 33), and in patients not treated with any ASM (n = 142). Enzyme-inducing ASMs included carbamazepine, phenytoin, phenobarbital, primidone, and oxcarbazepine. We collected clinical and laboratory data for analysis, and DOAC Cmax of patients taking LEV were compared with the other two groups. RESULTS: In 203 patients, 55% were female and the mean age was 78 ± 0.8 years. One hundred and eighty-six patients received apixaban and 17 patients received rivaroxaban. The proportion of patients with DOAC Cmax below their therapeutic range was 7.1% in the LEV group, 10.6% in the non-ASM group, and 36.4% in the EI-ASM group (p < 0.001). The odds of having DOAC Cmax below the therapeutic range (compared with control groups) was not significantly different in patients taking LEV (adjusted odds ratio 0.70, 95% confidence interval 0.19-2.67, p = 0.61), but it was 12.7-fold higher in patients taking EI-ASM (p < 0.001). In an analysis in patients treated with apixaban, there was no difference in apixaban Cmax between patients treated with LEV and non-ASM controls, and LEV clinical use was not associated with variability in apixaban Cmax in a multivariate linear regression. CONCLUSIONS: In this study, we show that unlike EI-ASMs, LEV clinical use was not significantly associated with lower apixaban Cmax and was similar to that in patients not treated with any ASM. Our findings suggest that the combination of LEV with apixaban and rivaroxaban may not be associated with decreased apixaban and rivaroxaban Cmax. Therefore, prospective controlled studies are required to examine the possible non-pharmacokinetic mechanism of the effect of the LEV-apixaban or LEV-rivaroxaban combination on patients' outcomes.

Comparison of High- and Low-Dose Rivaroxaban Regimens in Elderly East Asian Patients With Atrial Fibrillation.

BACKGROUND: In the Rivaroxaban Once-daily oral direct factor Xa inhibition Compared with vitamin K antagonism for prevention of stroke and Embolism Trial in Atrial Fibrillation (ROCKET AF) trial, rivaroxaban 20 mg was the on-label dose, and the dose-reduction criterion for rivaroxaban was a creatinine clearance of < 50 mL/min. Some Asian countries are using reduced doses label according to the J-ROCKET AF trial. The aim of this study was to assess the safety and efficacy of a high-dose rivaroxaban regimen (HDRR, 20/15 mg) and low-dose rivaroxaban regimen (LDRR, 15/10 mg) among elderly East Asian patients with atrial fibrillation (AF) in real-world practice. METHODS: This study was a multicenter, prospective, non-interventional observational study designed to evaluate the efficacy and safety of rivaroxaban in AF patients > 65 years of age with or without renal impairment. RESULTS: A total of 1,093 patients (mean age, 72.8 ± 5.8 years; 686 [62.9%] men) were included in the analysis, with 493 patients allocated to the HDRR group and 598 patients allocated to the LDRR group. A total of 765 patients received 15 mg of rivaroxaban (203 in the HDRR group and 562 in the LDRR group). There were no significant differences in the incidence rates of major bleeding (adjusted hazard ratio [HR], 0.64; 95% confidential interval [CI], 0.21-1.93), stroke (adjusted HR, 3.21; 95% CI, 0.54-19.03), and composite outcomes (adjusted HR, 1.13; 95% CI, 0.47-2.69) between the HDRR and LDRR groups. CONCLUSION: This study revealed the safety and effectiveness of either dose regimen of rivaroxaban in an Asian population for stroke prevention of AF. Considerable numbers of patients are receiving LDRR therapy in real-world practice in Asia. Both regimens were safe and effective for these patients. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT04096547.

Direct oral anticoagulants in trauma patients.

PURPOSE OF REVIEW: Direct oral anticoagulants (DOACs) are increasingly prescribed for prevention of thromboembolic events. Thus, trauma care providers are facing a steadily raising number of injured patients on DOACs. RECENT FINDINGS: Despite a predictable pharmacokinetic profile, the resulting plasma levels of trauma patients upon admission and bleeding risks remain uncertain. Therefore, recent guidelines recommend the measurement of DOAC plasma concentrations in injured patients. Alternatively, DOAC specific visco-elastic tests assays can be applied to identify DOAC patients at bleeding risk.Bleeding complications in trauma patients on DOACs are generally higher compared to nonanticoagulated subjects, but comparable to vitamin K antagonists (VKAs). In particular, a traumatic brain injury does not carry an increased risk of intracranial bleeding due to a DOAK intake compared to VKAs. Current studies demonstrated that up to 14% of patients with a hip fracture are on DOACs prior to surgery. However, the majority can be operated safely within a 24h time window without an increased bleeding rate.Specific antagonists facilitate rapid reversal of patients on DOACs. Idarucizumab for dabigatran, and andexanet alfa for apixaban and rivaroxaban have been approved for life threatening bleeding. Alternatively, prothrombin complex concentrate can be used. Dialysis is a potential treatment option for dabigatran and haemoabsorption with special filters can be applied in patients on FXa-inhibitors. SUMMARY: Current guidelines recommend the measurement of DOAC plasma levels in trauma patients. Compared to VKAs, DOACs do not carry a higher bleeding risk. DOAC specific antagonists facilitate the individual bleeding management.

The impact of factor Xa inhibitors on bleeding risk in patients with respiratory diseases.

It is unclear which factor Xa (FXa) inhibitors are associated with higher bleeding risk in patients with respiratory diseases, and there are no studies on the association between prothrombin time-international normalized ratio (PT-INR) and bleeding risk. We conducted a retrospective cohort study comparing 1-year-outcomes and PT-INR between patients with respiratory diseases treated with rivaroxaban (R group, n = 82) or edoxaban (E group, n = 138) for atrial fibrillation or venous thromboembolism from 2013 to 2021. The most frequent event of all bleeding discontinuations was respiratory bleeding in both groups (7.3 and 4.3%, respectively). The cumulative incidence of bleeding discontinuation was significantly higher in the R group (25.6%) than in the E group (14.4%) (hazard ratio [HR], 2.29; 95% confidence interval [CI] 1.13-4.64; P = 0.023). PT-INR after initiation of therapy significantly increased and was higher in the R group than in the E group (median value, 1.4 and 1.2, respectively; P < 0.001). Multivariate analysis using Cox proportional hazards and Fine-Gray models revealed that PT-INR after initiation of therapy was an independent risk factor of bleeding discontinuation events (HR = 4.37, 95% CI 2.57-7.41: P < 0.001). Respiratory bleeding occasionally occurs in patients receiving FXa inhibitors, and monitoring the PT-INR may need to ensure safety.

Age-related variation in coagulation factors in non-valvular atrial fibrillation patients receiving direct oral anticoagulants.

Age is a significant risk factor for ischemic stroke. However, the influence of aging on coagulation parameters in non-valvular atrial fibrillation (NVAF) patients treated with direct oral anticoagulants (DOACs) remains unclear. A total of 775 samples were collected from 224 NVAF patients receiving apixaban, edoxaban or rivaroxaban. The samples were categorized into three age groups: (i) ≤ 64 years, (ii) 65-74 years, and (iii) ≥ 75 years (apixaban: N = 48, 108, 119; edoxaban: N = 63, 68, 126; rivaroxaban: N = 115, 90, 38, respectively). Coagulation parameters including fibrinogen (Fbg), factor II, factor V, factor VII, factor X, and D-dimer, were compared between the three age groups for each drug. The slopes in the correlation between drug concentrations and modified diluted prothrombin time (mdPT) were also assessed. Fbg and factor V increased with age, while factor II and factor X decreased. Factor VII and D-dimer showed no significant differences across age categories. The slope in response to drug concentrations was similar between the age groups. In NVAF patients treated with apixaban, edoxaban and rivaroxaban, some coagulation parameters exhibited age-related variation. However, the response of mdPT to drug concentration was consistent across age categories.

Dispensing pharmacy chains and direct anticoagulants: Potential associations with patient outcomes.

PURPOSE: Pharmacy chains can differ with respect to the characteristics of their patient populations as well as their nonprescription products, services, and practices, and thus may serve as a surrogate for potential unmeasured confounding in observational studies of prescription drugs. This study evaluates whether a single-source drug can have different patient outcomes based on the dispensing pharmacy chain. METHODS: Separate analyses for two anticoagulant drugs, rivaroxaban and apixaban, were conducted using Medicare Fee-for-Service claims evaluating the association between dispensing pharmacy chain and outcomes of acute myocardial infarction, ischemic stroke, intracranial hemorrhage, gastrointestinal (GI) bleeding, all-cause mortality, and major GI bleeding. Inverse probability of treatment weighting (IPTW) was used to balance baseline covariates across pharmacy chain cohorts, and outcome association was assessed with a Cox Proportional Hazards model. RESULTS: We observed no differences in outcomes across pharmacy chains for apixaban recipients. Rivaroxaban recipients from pharmacy chain C, however, had lower rates of GI bleeding (adjusted HR 0.83; 95% CI 0.69-1.00) and ischemic stroke (adjusted HR 0.57; 95% CI 0.38-0.87) as compared to chain A in primary analyses with a 3-day grace period. The results moved closer to the null when 14- and 30-day grace periods were implemented. CONCLUSIONS: These results suggest that dispensing pharmacy chains may have the potential to act as a confounder of associations between drug exposure and outcome in some observational studies. Additional studies of potential confounding by pharmacy chain are needed. Further evaluation of potential pharmacy chain effects on safe use would be of value.

Andexanet Alfa: What We Have Learned from Clinical Trials and Real-World Data.

Andexanet alfa is a specific reversal agent for factor Xa inhibitors with immediate reversal of their anticoagulant effect. Andexanet alfa is currently approved for use in patients treated with rivaroxaban and apixaban who have life-threatening or uncontrolled bleeding. New data from both controlled clinical trials and real-world experience are continuously being published, providing greater insight into the clinical characteristics of the drug, such as efficacy and safety. It is worth considering that andexanet alfa could be of benefit in a variety of different clinical scenarios where patients receiving treatment with apixaban and rivaroxaban (and endoxaban) have life-threatening conditions. These different clinical scenarios, which range from pre-treatment of urgent surgery, especially neurosurgical interventions, and concomitant use of andexanet alfa and prothrombin complex concentrate to onset of bleeding more than 6 h prior to admission, should be clarified as well as the issue of "low/high" dose of andexanet alfa and the need for baseline anti-Xa inhibitor levels measured by point-of-care testing. Finally, management of patients at high risk of thrombosis or recent arterial/venous thrombotic events needs to be further explored. In this current opinion, we address these urgent questions in the light of recent literature and clinical trial data.

Therapy adherence, safety and efficacy of rivaroxaban in prevention of venous thromboembolism in patients with hip or knee endoprosthesis.

PURPOSE: Rivaroxaban is a potent, selective direct inhibitor of factor Xa. The aim of this study was to evaluate the therapy adherence, safety and efficacy of rivaroxaban therapy in reducing the risk of venous thromboembolism in patients undergoing elective hip or knee replacement. METHODS: The prospective, post-marketing clinical trial was conducted on adult patients after knee or hip endoprosthesis. Data were collected at the baseline and three control visits (five days, a month and three months after the baseline). Morisky Medication Adherence Scale (MMAS-8) was used for evaluation of therapy adherence. RESULTS: The study included 60 patients who received rivaroxaban therapy in a dose of 10 mg once a day. A low adherence to the drug was observed in 15% patients. All patients had an average MMAS-8 score in the range of high adherence 0.65 ± 0.90. Symptomatic venous thromboembolism was observed in two patients with numerous risk factors. No major bleeding was recorded during entire follow-up period. During the five-day postoperative in-hospital follow-up, signs of wound complications were recorded in 8 (13.3%) patients, and 4 (6.7%) of them underwent surgical revision of the wound. CONCLUSION: Generally, there was high adherence to rivaroxaban therapy, but low adherence was present in 15% of patients. Rivaroxaban showed good safety and efficacy. However, high proportion of wound complications and patients needing surgical revision of the wound should be further evaluated through larger studies.

Clinical and molecular determinants of bleeding-related adverse outcomes in high-grade glioma.

PURPOSE: Cancer is an independent risk factor for the development of venous thromboembolism (VTE). However, patients with high-grade glioma (HGG) including glioblastoma (GBM) are at a particularly high risk of VTE with an incidence up to 20-30% per year. Patients are often placed on anticoagulation if they are found to have VTE. However, patients with primary brain tumors such as HGG are at increased risk for intracerebral hemorrhage (ICH) even without the administration of anticoagulation. The combination of risk factors for ICH with anticoagulation and HGG complicates decision-making. Currently it is not known which of the direct oral anticoagulants (DOACs) are safest for patients with HGG in terms of adverse bleeding-related outcomes such as ICH. Furthermore, a deeper understanding of the clinical and molecular determinants of bleeding-related adverse outcomes in HGG is not fully characterized. METHODS: In this retrospective study, we identified and gathered data on 75 consecutive patients with pathology-confirmed HGG with hospital encounters at two academic medical center hospitals in Austin between July 1, 2017 and June 30, 2022. We compared clinical and treatment-related factors among cohorts who had received various forms of anticoagulation or no anticoagulation. RESULTS: Patients who were on rivaroxaban (3/7 (43%)) had a statistically significant association with more bleeding-related adverse events compared to those on apixaban (0/12 (0%)) or enoxaparin (0/5 (0%), p = 0.022) even though the groups were similar in characteristics including total time on the respective anticoagulation. Patients on anticoagulation vs those never on anticoagulation did not differ in terms of their studied demographic and clinical characteristics. Intriguingly, logistic regression analysis revealed that patients Astrocytoma, isocitrate dehydrogenase (IDH) mutant, grade 4 had a significant association with more adverse bleeding-related events even when controlling for other relevant factors (Odds Ratio compared to reference GBM: 49.4, 95% CI: 2.8, 2084.7; p = 0.013). CONCLUSION: In this study we found that the use of rivaroxaban was associated with more bleeding-related events compared to apixaban and enoxaparin in patients with high-grade glioma. In this study we also found that the diagnosis of astrocytoma, IDH mutant, grade 4 was associated with more bleeding events. However, this is based on a small study and there is a need for larger studies to further evaluate these results.

Identifying the highest risk vascular patients: Insights from the XATOA registry.

BACKGROUND: Patients with coronary and peripheral artery disease (PAD) have a residual risk of major adverse cardiovascular and limb events despite standards of care. Among patients with coronary artery disease (CAD) and/or PAD selected for low dose rivaroxaban (2.5 mg BID) and aspirin, we sought to determine the highest risk vascular patients. METHODS: Xarelto pluc Acetylsalicylic acid: Treatment patterns and Outcomes in patients with Atherosclerosis (XATOA) is a single-arm registry of CAD and/or PAD patients. All participants were initiated on low dose rivaroxaban (2.5 mg BID) and aspirin. We report the incidence risk of major adverse cardiovascular events (MACE) or major adverse limb events (MALE) and major bleeding. A classification and regression tree analysis determined independent subgroups. RESULTS: Between November 2018 and May 2020, 5,808 participants were enrolled in XATOA; 5,532 were included in the full analysis. The median follow-up (interquartile range) was 462 (371-577) days. The incidence risk per 100 patient-years of MACE or MALE was highest among participants with polyvascular disease (2 or more vascular beds affected, n = 2,889). The incidence risk was 9.16 versus 2.48 per 100 patient-years in polyvascular and nonpolyvascular patients respectively. Other subgroups of high-risk patients included participants 75 years or older, with a history of diabetes, heart failure, or chronic renal insufficiency (CRI). Rates of major bleeding were low overall. A classification and regression tree analysis showed that polyvascular disease was the most dominant factor separating higher from lower risk participants, and this was heightened with CRI or diabetes. CONCLUSION: Patients with polyvascular disease represent a substantial subset of patients in clinical practice and should be prioritized to receive maximal medical therapy including low dose rivaroxaban (2.5 mg BID) and aspirin.

Switching from Dual Antiplatelet Therapy with Aspirin Plus a P2Y12 Inhibitor to Dual Pathway Inhibition with Aspirin Plus Vascular-Dose Rivaroxaban: The Switching Anti-Platelet and Anti-Coagulant Therapy (SWAP-AC) Study.

BACKGROUND: To date, there are no data on switching to dual pathway inhibition (DPI) patients who have completed a guideline-recommended dual antiplatelet therapy (DAPT) regimen. OBJECTIVES: To assess the feasibility of switching from DAPT to DPI and to compare the pharmacodynamic (PD) profiles of these treatments. METHODS: This was a prospective, randomized, PD study conducted in 90 patients with chronic coronary syndrome (CCS) on DAPT with aspirin (81 mg/qd) plus a P2Y12 inhibitor (clopidogrel [75 mg/qd; n = 30], ticagrelor [90 mg/bid; n = 30], or prasugrel [10 mg/qd; n = 30]). Patients in each cohort were randomized to maintain DAPT or switch to DPI (aspirin 81 mg/qd plus rivaroxaban 2.5 mg/bid). PD assessments included: VerifyNow P2Y12 reaction units; light transmittance aggregometry following stimuli with adenosine diphosphate (ADP), tissue factor (TF), and a combination of collagen, ADP, and TF (maximum platelet aggregation %); thrombin generation (TG). Assays were performed at baseline and 30 days postrandomization. RESULTS: Switching from DAPT to DPI occurred without major side effects. DAPT was associated with enhanced P2Y12 inhibition, while DPI with reduced TG. Platelet-mediated global thrombogenicity (primary endpoint) showed no differences between DAPT and DPI in the ticagrelor (14.5% [0.0-63.0] vs. 20.0% [0.0-70.0]; p = 0.477) and prasugrel (20.0% [0.0-66.0] vs. 4.0% [0.0-70.0]; p = 0.482), but not clopidogrel (27.0% [0.0-68.0] vs. 53.0% [0.0-81.0]; p = 0.011), cohorts. CONCLUSION: In patients with CCS, switching from different DAPT regimens to DPI was feasible, showing enhanced P2Y12 inhibition with DAPT and reduced TG with DPI, with no differences in platelet-mediated global thrombogenicity between DPI and ticagrelor- and prasugrel-, but not clopidogrel-, based DAPT. CLINICAL TRIAL REGISTRATION: http://www. CLINICALTRIALS: gov Unique Identifier: NCT04006288.

Comparison of the Efficacy and Safety of Rivaroxaban and Low Molecular Heparin in Preventing Venous Thromboembolism in Inpatient Cancer Patients.

BACKGROUND: There are few studies on using rivaroxaban and low molecular heparin (LMWH) to prevent venous thromboembolism (VTE) in hospitalized cancer patients. OBJECTIVE: We conducted a retrospective study to evaluate the efficacy and safety of rivaroxaban versus LMWH for the primary prevention of VTE in inpatient cancer patients. METHODS: Information on patients was collected through 6-month follow-up and medical record inquiries. Clinical outcomes included VTE, total bleeding, thrombosis, major bleeding, minor bleeding, all-cause death, and a composite endpoint of bleeding, thrombosis, and death. RESULTS: A total of 602 hospitalized cancer patients were included in this study. During 6 months of follow-up, there were 26 VTE events (8.6%), 42 total bleeding events (7.0%), 62 all-cause deaths (10.3%), and 140 composite endpoints (23.3%). After adjusting for various confounding factors, there were no significant differences between the rivaroxaban and LMWH for VTE events (OR = 0.851, 95% CI [0.387-1.872], P=0.688), total bleeding (OR = 1.690, 95% CI [0.768-3.719], P = 0.192], thrombosis events (OR = 0.919, 95% CI [0.520-1.624], P = 0.772], major bleeding (OR = 0.276, 95% CI [0.037-2.059], P = 0.209), all-cause death (OR = 0.994, 95% CI [0.492-2.009], P = 0.987), and composite endpoints (OR = 0.994, 95% CI [0.492-2.009], P = 0.987), while minor bleeding (OR = 3.661 95% CI [1.000-7.083], P = 0.050) was significantly higher in the rivaroxaban than in the LMWH. CONCLUSIONS AND RELEVANCE: In thromboprophylaxis in inpatient cancer patients, rivaroxaban has a similar rate of VTE and bleeding events as LMWH. Our results may provide a reference for the clinical use of rivaroxaban to prevent VTE in hospitalized cancer patients.

Bioequivalence Study of Capsules versus Film Tablets Containing Rivaroxaban in Healthy Caucasian Subjects under Fasting and Fed Conditions.

The bioequivalence (BE) of orally administered capsules versus film tablets containing 20  and 10 mg of rivaroxaban was assessed in 2 single-dose, open-label, randomized 2-way crossover trials with a washout period of at least 1 week. The study for the 10 mg strength was conducted under fasting conditions (n = 68) and the study for the 20 mg strength under fed conditions (n = 52). Blood samples were collected over a 36-hour period and concentrations were assayed using a liquid chromatography tandem mass spectrometry method. Pharmacokinetic (PK) evaluation was performed with the program Phoenix WinNonlin, for non-compartmental assessment of data. After administration of 10 mg rivaroxaban under fasting conditions, mean Area Under the time - concentration Curve until the last blood sampling point (AUCt ), Area Under the time - concentration Curve until infinity (AUC∞ ), and maximum plasma concentration (Cmax ) were comparable (972 ng/mL*h, 1048 ng/mL*h, and 111 ng/mL, respectively, for the test and 1013 ng/mL*h, 1070 ng/mL*h and 130 ng/mL, respectively, for the reference formulation). Mean AUCt , AUC∞ , and Cmax were also comparable under fed conditions after administration of 20 mg rivaroxaban (2145 ng/mL*h, 2198 ng/mL*h and 275 ng/mL, respectively, for the test and 1856 ng/mL*h, 1916 ng/mL*h and 240 ng/mL, respectively, for the reference formulation). The 90% confidence intervals for all PK parameters were within the acceptance range of 80%-125%, suggesting BE between the generic product and the innovator product in healthy Caucasian male subjects. A clinically relevant difference in the tolerability and safety of the treatments was not detected. Study results indicated that the capsule formulations were bioequivalent with the film tablet formulations.

Efficacy and Safety of Different Doses of Rivaroxaban and Risk Factors for Bleeding in Elderly Patients with Venous Thromboembolism: A Real-World, Multicenter, Observational, Cohort Study.

INTRODUCTION: Venous thromboembolism (VTE) consists of deep vein thrombosis (DVT) and pulmonary embolism (PE). Rivaroxaban is a direct oral anticoagulant (DOAC) inhibiting activated coagulation factor X (FXa), and exerts several advantages in the treatment of VTE compared to conventional therapy. However, the efficacy and safety of rivaroxaban in elderly patients with VTE was still poorly understood. METHODS: The study was carried out using an observational and non-interventional approach. A total of 576 patients aged ≥ 60 years with newly diagnosed VTE were included in the study. All patients received rivaroxaban with recommended treatment duration of ≥ 3 months for secondary prevention. In addition, 535 elderly patients with various diseases except VTE were included in the study in a retrospective and randomized way. RESULTS: The total bleeding rate was 12.2% (70/576). Major bleeding and non-major clinically relevant (NMCR) bleeding occurred in 4 (0.69%) patients and 5 (0.87%) patients, respectively. The rate of recurrent VTE was 5.4%. The mean level of D-dimers was increased by 467.2% in the elderly patients with VTE compared with the elderly patients without VTE. The elderly patients with VTE receiving rivaroxaban at a dose of 10 mg once daily (n = 134) had lower risk for bleeding (3.7% vs 14.7%; P = 0.001) and a similar rate of recurrent VTE (4.5% vs 5.7%; P = 0.596) as compared to the elderly patients with VTE receiving rivaroxaban at higher doses including 15 mg once daily and 20 mg once daily (n = 442). In addition, age, concomitant aspirin, hemoglobin, activated partial thromboplastin time (APTT), and rivaroxaban doses were independent predictive factors for bleeding events. CONCLUSIONS: The study suggested that a dose of 10 mg once daily should be the priority in elderly patients with VTE receiving long-term rivaroxaban anticoagulation therapy in view of reduced bleeding risk.