Bleeding Outcomes in Patients Treated With Asundexian in Phase II Trials.

BACKGROUND: Phase II trials of asundexian were underpowered to detect important differences in bleeding. OBJECTIVES: The goal of this study was to obtain best estimates of effects of asundexian vs active control/placebo on major and clinically relevant nonmajor (CRNM) and all bleeding, describe most common sites of bleeding, and explore association between asundexian exposure and bleeding. METHODS: We performed a pooled analysis of 3 phase II trials of asundexian in patients with atrial fibrillation (AF), recent acute myocardial infarction (AMI), or stroke. Bleeding was defined according to the International Society on Thrombosis and Hemostasis (ISTH) criteria. RESULTS: In patients with AF (n = 755), both asundexian 20 mg and 50 mg once daily vs apixaban had fewer major/CRNM events (3 of 249; incidence rate [IR] per 100 patient-years 5.47 vs 1 of 254 [IR: not calculable] vs 6 of 250 [IR: 11.10]) and all bleeding (12 of 249 [IR: 22.26] vs 10 of 254 [IR: 18.21] vs 26 of 250 [IR: 50.56]). In patients with recent AMI or stroke (n = 3,409), asundexian 10 mg, 20 mg, and 50 mg once daily compared with placebo had similar rates of major/CRNM events (44 of 840 [IR: 7.55] vs 42 of 843 [IR: 7.04] vs 56 of 845 [IR: 9.63] vs 41 of 851 [IR: 6.99]) and all bleeding (107 of 840 [IR: 19.57] vs 123 of 843 [IR: 22.45] vs 130 of 845 [IR: 24.19] vs 129 of 851 [IR: 23.84]). Most common sites of major/CRNM bleeding with asundexian were gastrointestinal, respiratory, urogenital, and skin. There was no significant association between asundexian exposure and major/CRNM bleeding. CONCLUSIONS: Analyses of phase II trials involving >500 bleeds highlight the potential for improved safety of asundexian compared with apixaban and similar safety compared with placebo. Further evidence on the efficacy of asundexian awaits the results of ongoing phase III trials.

Rivaroxaban or Aspirin for Extended Treatment of Venous Thromboembolism.

BACKGROUND: Although many patients with venous thromboembolism require extended treatment, it is uncertain whether it is better to use full- or lower-intensity anticoagulation therapy or aspirin. METHODS: In this randomized, double-blind, phase 3 study, we assigned 3396 patients with venous thromboembolism to receive either once-daily rivaroxaban (at doses of 20 mg or 10 mg) or 100 mg of aspirin. All the study patients had completed 6 to 12 months of anticoagulation therapy and were in equipoise regarding the need for continued anticoagulation. Study drugs were administered for up to 12 months. The primary efficacy outcome was symptomatic recurrent fatal or nonfatal venous thromboembolism, and the principal safety outcome was major bleeding. RESULTS: A total of 3365 patients were included in the intention-to-treat analyses (median treatment duration, 351 days). The primary efficacy outcome occurred in 17 of 1107 patients (1.5%) receiving 20 mg of rivaroxaban and in 13 of 1127 patients (1.2%) receiving 10 mg of rivaroxaban, as compared with 50 of 1131 patients (4.4%) receiving aspirin (hazard ratio for 20 mg of rivaroxaban vs. aspirin, 0.34; 95% confidence interval [CI], 0.20 to 0.59; hazard ratio for 10 mg of rivaroxaban vs. aspirin, 0.26; 95% CI, 0.14 to 0.47; P<0.001 for both comparisons). Rates of major bleeding were 0.5% in the group receiving 20 mg of rivaroxaban, 0.4% in the group receiving 10 mg of rivaroxaban, and 0.3% in the aspirin group; the rates of clinically relevant nonmajor bleeding were 2.7%, 2.0%, and 1.8%, respectively. The incidence of adverse events was similar in all three groups. CONCLUSIONS: Among patients with venous thromboembolism in equipoise for continued anticoagulation, the risk of a recurrent event was significantly lower with rivaroxaban at either a treatment dose (20 mg) or a prophylactic dose (10 mg) than with aspirin, without a significant increase in bleeding rates. (Funded by Bayer Pharmaceuticals; EINSTEIN CHOICE ClinicalTrials.gov number, NCT02064439 .).

[Rivaroxaban for thrombosis prophylaxis in extensive hip and knee operations. Subanalysis of the German cohort (XAMOS-DE) of non-interventional study XAMOS]. / Rivaroxaban in der Thromboseprophylaxe bei großen Hüft- und Knieoperationen : Subanalyse der deutschen Kohorte der nicht interventionellen XAMOS-Studie.

BACKGROUND: In global admission studies (RECORD I-IV) Rivaroxaban and enoxaparin as a standard prophylaxis were comparable in safety of treatment, but rivaroxaban appeared more effective in prevention of venous thromboembolism (VTE) when used in elective hip and knee replacement. The worldwide non-interventional cohort study XAMOS confirmed these results in the clinical routine compared to proven anticoagulants. METHOD: Efficacy and safety of rivaroxaban was to be compared with the standard prophylaxis in the prevention of VTE after elective hip and knee replacement surgery in clinical practice in Germany. For this purpose a subanalysis of the 2,719 patients (XAMOS-DE) included in XAMOS in German study centers was performed. RESULTS: Out of 2,719 patients in 32 study centers 1,333 patients obtained rivaroxaban and 1,386 patients obtained standard prophylaxis. The incidence of symptomatic VTE-events (0.9% with rivaroxaban vs. 1.1% with standard prophylaxis) and severe bleeding by RECORD (0.5% vs. 0.9%) and EMA criteria (2.9 % vs. 3.0%) was similar in both groups. Most of the patients treated with rivaroxaban rated tolerability as "very good" and therapy as "very patient-friendly". CONCLUSION: The results from XAMOS-DE confirm in clinical practice the favorable benefit-risk ratio of rivaroxaban, as well as the current S3 guidelines for thromboembolism prophylaxis with rivaroxaban in elective hip and knee replacement.

The effects of timing of prophylaxis, type of anesthesia, and use of mechanical methods on outcome in major orthopedic surgery - subgroup analyses from 17,701 patients in the XAMOS study.

PURPOSE: Real-world data on the use of rivaroxaban in the perioperative period in patients undergoing major orthopedic surgery are limited. Subsets of data from the Phase IV, non-interventional XAMOS study were analyzed to explore the potential influence of timing of the first thrombo prophylactic dose, type of anesthesia, and concomitant mechanical prophylaxis on clinical outcomes in patients undergoing major orthopedic surgery in routine clinical practice. PATIENTS AND METHODS: In XAMOS, 8,778 patients received rivaroxaban (10 mg once daily) and 8,635 received standard-of-care (SOC) pharmacological prophylaxis (safety population). Crude incidences of symptomatic thromboembolic and treatment-emergent bleeding events were analyzed according to timing of the first postoperative thromboprophylactic dose, use of general or neuraxial anesthesia, and use of mechanical prophylaxis with pharmacological thromboprophylaxis. RESULTS: In the rivaroxaban group, the incidences of symptomatic thromboembolic events were 0.7%, 1.0%, and 0.7% in patients receiving the first thromboprophylactic dose at ≤6 hours, >6 hours to ≤10 hours, and >10 hours to ≤24 hours after surgery, respectively. In the SOC group, the incidence of symptomatic thromboembolic events was slightly higher when the postoperative dose was given at >10 hours to ≤24 hours (1.8% vs 1.1% at ≤6 hours and 1.3% at >6 hours to ≤10 hours). The antithrombotic effect of rivaroxaban was maintained in comparison to the SOC group. The incidence of major bleeding (RECORD trial definition) was low and similar between the two treatment groups and was not influenced by timing of the first thromboprophylactic dose. Neuraxial anesthesia was used more than any other form of anesthesia for both hip and knee surgery; the effectiveness of rivaroxaban was not influenced by the type of anesthesia used. No spinal hematomas were reported in patients receiving neuraxial anesthesia in either treatment group. Use of mechanical thromboprophylaxis in addition to rivaroxaban or SOC pharmacological prophylaxis did not reduce the risk of thromboembolic events further. CONCLUSION: The effectiveness and safety of rivaroxaban in patients undergoing major orthopedic surgery in routine clinical practice were maintained irrespective of timing of the first postoperative dose within 24 hours after surgery, the type of anesthesia, and the additional use of mechanical thromboprophylaxis.

Rivaroxaban compared with standard thromboprophylaxis after major orthopaedic surgery: co-medication interactions.

AIM: The aim of the present study was to analyse concomitant drug use and its association with outcome in patients (N = 17 701) receiving rivaroxaban or standard of care (SOC) for the prevention of venous thromboembolism after major orthopaedic surgery in the non-interventional, phase IV XAMOS (Xarelto® in the prophylaxis of post-surgical venous thromboembolism after elective major orthopaedic surgery of hip or knee) study. METHODS: Concomitant drug use was at the discretion of the treating physician. Prespecified co-medications of interest were cytochrome P450 (CYP) 3A4/P-glycoprotein inhibitors/inducers, platelet aggregation inhibitors (PAIs) and nonsteroidal anti-inflammatory drugs (NSAIDs). Crude event incidences were compared between rivaroxaban and SOC groups. RESULTS: CYP3A4/P-glycoprotein inhibitor/inducer use was infrequent, in contrast to PAI (~7%) and NSAID (~52%) use. Rivaroxaban was associated with a lower incidence of overall symptomatic thromboembolic events compared with SOC, regardless of co-medication use. In both treatment groups, PAI users, with higher age and prevalence of cardiovascular co-morbidities, had similar higher (>7-fold) incidences of symptomatic arterial but not venous thromboembolic events compared with non-users. NSAID use had no influence on thromboembolic events. However, odds ratios (ORs) for major bleeding events (European Medicines Agency definition) were higher in NSAID users compared with non-users in rivaroxaban [OR = 1.50; 95% confidence interval (CI) 1.06, 2.13] and SOC (OR = 1.70; CI 1.16, 2.49) groups. In PAI users, ORs for major bleeding events were no different from those of non-users in both the rivaroxaban (OR = 1.49; CI 0.84, 2.65) and SOC (OR = 1.46; CI 0.82, 2.62) groups. CONCLUSIONS: Use of NSAIDs in XAMOS was frequent and associated with a higher frequency of bleeding events in patients receiving rivaroxaban or SOC, although the benefit-risk profile of rivaroxaban compared with SOC was maintained.

Rivaroxaban for Thromboprophylaxis After Fracture-Related Orthopedic Surgery in Routine Clinical Practice.

BACKGROUND: The risk of venous thromboembolism is high in patients undergoing fracture-related major orthopedic surgery, but data on pharmacological thromboprophylaxis are limited. This analysis evaluated the effectiveness and safety of rivaroxaban after fracture-related orthopedic surgery in routine care compared with other pharmacological thromboprophylaxis (standard of care [SOC]). METHODS: The study population comprised a subset of patients with lower-limb fracture from XArelto in the prophylaxis of post-surgical venous thromboembolism after elective Major Orthopaedic Surgery of hip or knee (XAMOS; a phase IV noninterventional study) and a XAMOS extension study (XAMOS-Extra). The study participants included patients who underwent surgery for hip/femur or lower-leg fractures (below-knee lower-leg fractures, eg, the tibia or foot). All adverse events were recorded, including symptomatic thromboembolic events and bleeding events. RESULTS: Data from 790 patients were available for analysis (n = 350 for rivaroxaban and n = 440 for SOC). The incidence of symptomatic thromboembolic events 3 months postsurgery was 0.57% (2 of the 350) in the rivaroxaban group and 1.14% (5 of the 440) in the SOC group (odds ratio [OR]: 0.50; 95% confidence interval [CI]: 0.10-2.59). Treatment-emergent major bleeding events occurred in 0.29% (1 of the 350) of patients receiving rivaroxaban and 0.45% (2 of the 440) of patients receiving SOC (OR: 0.63; 95% CI: 0.06-6.95). There were no cases of fatal or critical bleeding in either treatment group. The incidences of wound complications and any other adverse events were numerically lower with rivaroxaban compared with SOC. CONCLUSIONS: These data from routine practice demonstrate that rivaroxaban can provide effective thromboprophylaxis after fracture-related orthopedic surgery of the lower limb with a favorable safety profile.

Two doses of rivaroxaban versus aspirin for prevention of recurrent venous thromboembolism. Rationale for and design of the EINSTEIN CHOICE study.

Patients with unprovoked venous thromboembolism (VTE) are at high risk for recurrence. Although rivaroxaban is effective for extended VTE treatment at a dose of 20 mg once daily, use of the 10 mg dose may further improve its benefit-to-risk ratio. Low-dose aspirin also reduces rates of recurrent VTE, but has not been compared with anticoagulant therapy. The EINSTEIN CHOICE study is a multicentre, randomised, double-blind, active-controlled, event-driven study comparing the efficacy and safety of two once daily doses of rivaroxaban (20 and 10 mg) with aspirin (100 mg daily) for the prevention of recurrent VTE in patients who completed 6-12 months of anticoagulant therapy for their index acute VTE event. All treatments will be given for 12 months. The primary efficacy objective is to determine whether both doses of rivaroxaban are superior to aspirin for the prevention of symptomatic recurrent VTE, while the principal safety outcome is the incidence of major bleeding. The trial is anticipated to enrol 2,850 patients from 230 sites in 31 countries over a period of 27 months. In conclusion, the EINSTEIN CHOICE study will provide new insights into the optimal antithrombotic strategy for extended VTE treatment by comparing two doses of rivaroxaban with aspirin (clinicaltrials.gov NCT02064439).

Allogeneic blood transfusions and postoperative infections after total hip or knee arthroplasty.

BACKGROUND: Up to 70% of patients who undergo total hip or total knee arthroplasty receive blood transfusions. Using data from more than 12,000 patients assessed in the Phase-III RECORD (Regulation of Coagulation in Orthopedic Surgery to Prevent Deep Venous Thrombosis and Pulmonary Embolism) studies, we investigated whether allogeneic blood transfusion increases the risk of postoperative infection compared with autologous blood transfusion or no transfusion. METHODS: A post hoc analysis of the pooled RECORD data stratified patients into three groups according to the type of blood transfusion that they received: no transfusion (n = 6313), autologous blood transfusion (n = 1902), and allogeneic blood transfusion with or without autologous blood transfusion (n = 3962). The types of postoperative infection were recorded and included lower or upper respiratory tract and lung infection, bone and joint infection, wound inflammation or infection, urinary tract infection, and other infections. RESULTS: The rates of infection in patients receiving no transfusion or autologous blood transfusion were similar; therefore, data from these two groups were combined. The rate of any infection was 9.9% (392 of 3962) in patients receiving allogeneic blood transfusion and 7.9% (646 of 8215) in patients not receiving allogeneic blood transfusion with or without autologous blood transfusion (p = 0.003). The rates of lower or upper respiratory tract and lung infection (2.1% [eighty-five of 3962] versus 1.3% [109 of 8215]; p = 0.002) and of wound inflammation or infection (2.4% [ninety-four of 3962] versus 1.7% [138 of 8215]; p = 0.046) were significantly higher in patients receiving allogeneic blood transfusion compared with patients not receiving allogeneic blood transfusion. When comparing patients who had received allogeneic blood transfusion with those who had not received allogeneic blood transfusion, the rates of bone and joint infection (0.4% [fourteen of 3962] versus 0.2% [eighteen of 8215]; p = 0.056), of urinary tract infection (3.1% [123 of 3962] versus 2.5% [209 of 8215]; p = 0.551), and of other infections (3.0% [120 of 3962] versus 2.7% [225 of 8215]; p = 0.308) were not significantly different. CONCLUSIONS: The rates of any infection, lower or upper respiratory tract and lung infection, and wound inflammation or infection were significantly increased after elective total hip or total knee arthroplasty in patients receiving allogeneic blood transfusion compared with those receiving autologous blood transfusion or no blood transfusion.

A non-interventional comparison of rivaroxaban with standard of care for thromboprophylaxis after major orthopaedic surgery in 17,701 patients with propensity score adjustment.

Rivaroxaban demonstrated superior efficacy and a similar safety profile to enoxaparin for the prevention of venous thromboembolism in the phase III RECORD programme in patients undergoing elective hip or knee replacement surgery. The XAMOS study investigated adverse events, including bleeding and thromboembolic events, in patients receiving rivaroxaban for thromboprophylaxis in routine clinical practice. XAMOS was a non-interventional, open-label cohort study in patients undergoing major orthopaedic surgery of the hip or knee (predominantly elective arthroplasty), in which rivaroxaban was compared with other pharmacological thromboprophylaxis. All adverse events were documented, including symptomatic thromboembolic and bleeding events. Crude and adjusted incidences based on propensity score subclasses were calculated and compared between the rivaroxaban and standard-of-care groups. A total of 17,701 patients were enrolled from 252 centres in 37 countries. Crude incidences of symptomatic thromboembolic events three months after surgery in the safety population were 0.89% in the rivaroxaban group (n=8,778) and 1.35% in the standard-of-care group (n=8,635; odds ratio [OR] 0.65; 95% confidence interval [CI] 0.49-0.87), and 0.91% and 1.31% (weighted) in the propensity score-adjusted analysis (OR 0.69; 95% CI 0.56-0.85), respectively. Treatment-emergent major bleeding events (as defined in the RECORD studies) occurred in 0.40% and 0.34% of patients in the rivaroxaban and standard-of-care groups in the safety population (OR 1.19; 95% CI 0.73-1.95), and in 0.44% versus 0.33% (weighted) in the propensity score-adjusted analysis (OR 1.35; 95% CI 0.94-1.93), respectively.This study in unselected patients confirmed the favourable benefit-risk profile of rivaroxaban seen in the RECORD programme.