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

Drug-Drug Interactions Leading to Adverse Drug Reactions with Rivaroxaban: A Systematic Review of the Literature and Analysis of VigiBase

Rivaroxaban has become an alternative to vitamin K antagonists, which are considered to be at higher risk of drug-drug interactions (DDI) and more difficult to use. However, DDI do occur. We systematically reviewed studies that evaluated them and analysed DDI and subsequent adverse drug reactions (ADR) reported in spontaneous reports and VigiBase. We systematically searched articles that explored DDI with rivaroxaban up to 20 August 2018 via Medline, Embase and Google Scholar. Data from VigiBase came from spontaneous reports recovered up to 2 January 2018, where Omega was used to detect signals and identify potential interactions in terms of triplets with two drugs and one ADR. We identified 31 studies and 28 case reports. Studies showed significant variation in the pharmacokinetic for rivaroxaban, and an increased risk of haemorrhage or thromboembolic events due to DDI was highlighted in case reports. From VigiBase, a total of 21,261 triplets were analysed and the most reported was rivaroxaban–aspirin–gastrointestinal haemorrhage. In VigiBase, only 34.8% of the DDI reported were described or understood, and most were pharmacodynamic DDI. These data suggest that rivaroxaban should be considered to have significant potential for DDI, especially with CYP3A/P-gp modulators or with drugs that impair haemostasis.

H2S-mediated aerobic exercise antagonizes the hippocampal inflammatory response in CUMS-depressed mice

PURPOSE

This thesis was to investigate the protective effect and mechanism of H₂S-mediated aerobic exercise on the antagonism of the hippocampus inflammatory response in CUMS-depressed mice.

METHOD

Seventy C57BL/6 mice were randomly divided into control group (CG), model control group (MG), model exercise group (ME), H₂S enhanced group (HG) and H₂S enhanced and exercise group (HE). All mice except CG underwent a 28-day CUMS depression model. ME and HE received moderate-intensity aerobic treadmill training for 8 weeks. They were randomly selected for Nissl staining, Immunofluorescence, methylene blue colorimetric assay, and ELISA. The levels of IL-10 and TNF-ɑ were detected by qRT-PCR, and the expression levels of CBS and inflammatory-related factors in the hippocampus were detected.

RESULT

Compared with CG, the number of erections, modifications, and crossing grids in MG mice were significantly reduced, the time of forced swimming and forced tail suspension was significantly prolonged, the positive rate of 5-HT decreased, and the symptoms of depression were obvious. The positive rate of CD45⁺ increased, the inflammatory response was obvious, and the content of H₂S and the expression of biosynthetic enzyme CBS decreased. Aerobic exercise and H₂S-enhanced mice improved depressive symptoms, decreased proinflammatory factors, increased anti-inflammatory factors, increased H₂S content, increased CBS expression, and increased H₂S.

CONCLUSION

H₂S may participate in aerobic exercise to antagonize the inflammatory process of the hippocampus in CUMS-depressed mice by reducing the release of inflammatory response factors and hippocampus nerve injury factors, and effectively alleviate inflammatory injury in the hippocampus of depressed mice.

Real-World Analysis of Potential Pharmacokinetic and Pharmacodynamic Drug Interactions with Apixaban in Patients with Non-Valvular Atrial Fibrillation

Purpose

We conducted this study to assess the real-world prevalence, nature, predictors, and clinical necessity of apixaban pharmacokinetic (PK) and pharmacodynamic (PD) drug interactions in patients with non-valvular atrial fibrillation (NVAF) at a tertiary medical institution in Saudi Arabia.

Patients and Methods

An observational retrospective cohort analysis was conducted in adult patients diagnosed with NVAF receiving apixaban for stroke prevention from the period of June 2015 to May 2019.

Results

Of the 1271 patients included in the analysis, 611 (48.1%) patients had potential PD– or PK–drug interactions with apixaban. Of those, 490 (38.6%) patients had potential PD drug–drug interactions (DDIs) and 121 (9.5%) patients had potential PK-DDIs. PD-DDIs with apixaban were mainly with antiplatelet therapy followed by non-steroidal anti-inflammatory drugs and antidepressants. PK-DDIs with apixaban were mainly with combined P-gp/CYP3A4 inhibitors or inducers. History of minor bleeding was positively correlated with PD-DDIs with apixaban, ß coefficient = 0.455 (OR 1.58; 95% CI 1.01–2.45); p<0.05. History of acute coronary syndrome was positively correlated with PD-DDIs with apixaban, ß coefficient = 0.515 (OR 1.60; 95% CI 1.36–1.99); p<0.05. History of heart failure was positively correlated with PK-DDIs with apixaban, ß coefficient = 0.459 (OR 1.58; 95% CI 1.07–2.35); p<0.05. Almost 15% of the included patients had no clinical indication to receive the potential interacting drug with apixaban and about 20% of them were assuming an inappropriate apixaban dose according to the product package insert.

Conclusion

Pharmacodynamics and pharmacokinetics interactions are common in more than half of the patients with NVAF receiving apixaban for stroke prevention in this real-world analysis. Some of these interacting medications are not indicated. Drug–drug interactions should always be considered and monitored with apixaban with a regular assessment of the need for any interacting medication.

Drug-Drug Interactions with Direct Oral Anticoagulants

A large body of evidence suggests that not only direct anticoagulant effects but also major bleeding events and stroke prevention depend on plasma concentrations of direct oral anticoagulants (DOACs). Concomitant drugs that cause drug–drug interactions (DDIs) alter DOAC exposure by increasing or decreasing DOAC bioavailability and/or clearance; hence, they might affect the efficacy and safety of DOAC therapy. Patients with renal impairment already receive smaller DOAC maintenance doses because avoidance of elevated DOAC exposure might prevent serious bleeding events. For other causes of increased exposure such as DDIs, management is often less well-defined. Considering that DOAC patients are often older and have multiple co-morbidities, polypharmacy is highly prevalent. However, the effect of multiple drugs on DOAC exposure, and especially the impact of DDIs when concurring with drug–disease interactions as observed in renal impairment, has not been thoroughly elucidated. In order to provide effective and safe anticoagulation with DOACs, understanding the mechanisms and magnitude of DDIs appears relevant. Instead of avoiding drug combinations with DOACs, more DDI trials should be conducted and new strategies such as dose adjustments based on therapeutic drug monitoring should be investigated. However, dose adjustments based on concentration measurements cannot currently be recommended because evidence-based data are missing.

Pharmacokinetics of new oral anticoagulants: implications for use in routine care

INTRODUCTION

Since 2008, new oral anticoagulants (NOACs) have been approved for the prevention of venous thromboembolism (VTE) in patients receiving hip or knee replacement surgery, prevention of stroke and systemic embolism in patients with non-valvular atrial fibrillation (NVAF), treatment of deep vein thrombosis (DVT), and pulmonary embolism (PE). Premarketing randomized clinical trials (RCTs) of NOACs demonstrated their non-inferiority in terms of efficacy vs. warfarin (traditional oral anticoagulant - TOA), with lower risk of serious adverse drug reactions, especially cerebral hemorrhages. In clinical practice, pharmacokinetic aspects of NOACs have to be carefully taken into account to optimize the benefit-risk profile of these drugs. Areas covered: An overview of major issues related to pharmacokinetics of NOACs, such as drug-drug interactions, over- and underdosage in special populations (e.g. elderly, underweight, and chronic kidney disease patients), and impact on adherence and persistence to NOACs therapy and ultimately clinical outcomes in real-world setting, is provided. Expert opinion: NOACs have been proven to be a better option than traditional anticoagulants due to better tolerability and ease of use. However, given specific pharmacokinetic characteristics, NOAC therapy has to be carefully tailored and monitored in relation to patient characteristics with the final goal of maximizing benefits and minimizing risks.

An analysis on distribution and inter-relationships of biomarkers under rivaroxaban in Japanese patients with non-valvular atrial fibrillation (CVI ARO 1)

Prothrombin time (PT) has been widely used for measuring anticoagulation intensity under rivaroxaban therapy, but precise information has not been well established yet. Consecutive 96 non-valvular atrial fibrillation (NVAF) under rivaroxaban between Jan/June, 2015 were recruited. Serum concentration (SC) and PT with 5 representative reagents available in Japan (Neoplastin Plus®, Thromborel S®, Thrombocheck PT®, Thrombocheck PT Plus®, and Recombiplastin®) at 2-4 hours after (peak) and before intake of rivaroxaban (trough) were measured at outpatient clinic in the cardiovascular institute (CVI ARO study 1). Nonlinear mixed-effects modelling was used to model the population pharmacokinetics and pharmacodynamics of rivaroxaban. An oral one-compartment model was employed to describe the population pharmacokinetics of rivaroxaban. The pharmacokinetics of rivaroxaban were affected by creatinine clearance, alanine aminotransferase, and use of CYP3A4 or P-gp inhibitors. PTs with 5 reagents were predicted by pharmacodinamic models with SC, hematocrit, serum albumin, and age, with medium predicting ability (highest/lowest R2 = 0.746/0.658 in Recombiplastin/Thromborel S, respectively). This population analysis in NVAF patients under rivaroxaban therapy demonstrated that pharmacokinetics of rivaroxaban was described by an oral one-compartment model with expected covariates, and can be assessed by PT with available reagents in Japan with medium predicting ability.

The practice pattern of anticoagulation prophylaxis for patients undergoing total hip replacement in a major orthopaedic centre; a retrospective review

METHODS

In a major centre for orthopaedic surgery, we retrospectively analysed 1,469 patients who underwent elective hip replacement since 2010. All patients but 2 received anticoagulation postoperatively and rivaroxaban was the preferred choice for anticoagulation.

RESULTS

The incidence of all adverse events in those who received rivaroxaban was 1.7%. Only 0.3% had a minor upper gastrointestinal bleed and 1.3% developed a minor wound bleeding or haematoma. The occurrence of symptomatic venous thromboembolism (VTE) was 0.2% of all patients.

CONCLUSIONS

In this analysis, the incidence of adverse events was lower than the previously 4 published national figures.

Hemopericardium with tamponade following rivaroxaban administration and its attenuation by CYP3A4 inhibitors

Novel oral anticoagulants including the factor Xa inhibitor rivaroxaban are important alternatives to warfarin for the prevention of thromboembolic stroke in patients with nonvalvular atrial fibrillation. The pharmacology and metabolism of these agents differ from those of the vitamin K antagonists used over the decades preceding their introduction. We present a case of spontaneous hemopericardium and cardiac tamponade following administration of rivaroxaban. A review of the patient's medications revealed a total of seven agents known to be metabolized through cytochrome P450 3A4 (CYP3A4), the major pathway for rivaroxaban metabolism. While most physicians are familiar with recommendations to monitor renal function in patients prescribed rivaroxaban, we suspect that many fail to evaluate possible interactions with other agents having CYP3A4 inhibitory or inducer activity.

Potential drug-drug interactions with direct oral anticoagulants in elderly hospitalized patients

Background

To determine the prevalence and nature of potential drug-drug interactions (DDIs) with direct oral anticoagulants (DOACs) in elderly hospitalized patients.

Methods

This was a retrospective observational study. Inclusion criteria were: aged over 65 years; taking apixaban, rivaroxaban or dabigatran; and admitted to the Repatriation General Hospital between April 2014 and July 2015. A list of clinically relevant 'perpetrator' drugs was compiled from product information, the Australian Medicines Handbook, the Australian National Prescribing Service resources, and local health network guidelines. The prevalence and nature of potential DDIs with DOACs was determined by comparing inpatient drug charts with the list of perpetrator drugs.

Results

There were 122 patients in the study with a mean age of 82 years. Most patients had nonvalvular atrial fibrillation and were taking DOACs to prevent thrombotic stroke (83%). Overall, 45 patients (37%) had a total of 54 potential DDIs. Thirty-five patients had potential pharmacodynamic DDIs with antidepressants, nonsteroidal anti-inflammatory drugs and antiplatelets (35/122, 29%). Nineteen patients had potential pharmacokinetic DDIs (19/122, 16%). Of these, 68% (13/19) were taking drugs that increase DOAC plasma concentrations (amiodarone, erythromycin, diltiazem or verapamil) and 32% (6/19) were taking drugs that decrease DOAC plasma concentrations (carbamazepine, primidone or phenytoin). There were no cases of patients taking contraindicated interacting drugs.

Discussion

Potential DDIs with DOACs in elderly hospital inpatients are relatively common, particularly interactions that may increase the risk of bleeding. The risk-benefit ratio of DOACs in elderly patients on polypharmacy should always be carefully considered.

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.