Safety and Effectiveness of Direct Oral Anticoagulants Versus Vitamin K Antagonists: Pilot Implementation of a Near-Real-Time Monitoring Program in Italy

Epidemiological surveillance of drug safety using cumulative sequential analysis in electronic healthcare data

BACKGROUND

Methods for safety signal detection in electronic healthcare data analysing data sequentially are being developed to meet the limitations of spontaneous reporting systems.

OBJECTIVES

This study aims to provide an overview of the literature on sequential analysis of electronic healthcare data and describe the development and testing of a novel epidemiological surveillance system.

METHODS

We searched Medline, Embase, PubMed, Scopus, Web of Science, and the Cochrane Library applying similar in- and exclusion criteria as those of a previous systematic review. The proposed system consisted of repeated cohort studies and was tested in an emulated prospective setting. Two signal evaluations were performed with several sensitivity analyses and a target trial emulation.

FINDINGS

In the literature, 11 studies analysed the data sequentially of which two applied traditional epidemiological methods. Epidemiological surveillance of several exposures and outcomes can be successfully conducted with the newly proposed sequential analysis of electronic healthcare data. Signal evaluation studies confirmed the results of the system.

CONCLUSIONS

Very few studies in the literature analysed data at multiple time points, although this seems to be a prerequisite for testing the methods in a realistic setting. We demonstrated the feasibility of a sequential surveillance system using electronic healthcare data.

Protocolized management of bleeding in hospitals in The Netherlands in patients treated with direct oral anticoagulants

OBJECTIVE

To investigate and describe the protocolized treatment of DOAC-related bleeds in all Dutch hospitals.

METHODS

From August to December 2020 a nationwide survey among all 70 hospitals in the Netherlands was conducted on their protocols for management of bleeding in patients treated with direct oral anticoagulants (DOACs, i.e. apixaban, edoxaban, rivaroxaban and dabigatran). The protocols were assessed the following characteristics: bleeding definitions (mild, moderate and severe bleed), diagnostic parameters (hemoglobin [Hb], loss of blood, surgical procedure needed, etc), first and second choice of treatment, effectiveness criteria and the level of evidence/references upon which protocols were based.

RESULTS

All 70 hospitals responded (100%). We received 69 protocols in total, 6 of which were identical because hospitals worked together. In 35 (50%) of the protocols a definition of minor, moderate or severe bleeds was described. Diagnostic parameters for bleeds were present in 2%, 41% and 47% of protocols for a mild, moderate and severe bleed. While the first choice treatment for severe bleeding under dabigatran was idarucizumab in 96% of protocols, considerably more therapeutic options (mostly different prothrombin complex concentrate (PCC) doses) are described for Xa inhibitors. When considering criteria for effectiveness more than 90% of protocols did not have a clear description.

CONCLUSION

This study provides an overview of the current state of protocols for management of DOAC-related bleeding in The Netherlands. Protocols vary in the content of information provided and often do not include information, especially for diagnostic criteria and criteria for establishing the effectiveness of the intervention. The results of this study can assist in improving and harmonizing the protocols.

Comparing direct oral anticoagulants and vitamin K antagonist use in morbidly obese patients with venous thromboembolism: A single center retrospective cohort study

Introduction: Limited data exists on the safety and efficacy of direct-acting oral anticoagulants (DOAC) use in morbidly obese patients with venous thromboembolism (VTE). Given the benefits of DOAC use over vitamin K antagonists (VKAs), in terms of monitoring requirements, and dietary and drug interactions, it is important to evaluate whether this is consistent in the higher risk for VTE recurrence morbidly obese group body mass index (BMI ≥ 40 kg/m2). Materials and methods: This retrospective, single-center cohort study included patients with a BMI of at least 40 kg/m2 who were admitted to Emory University Hospital from 1st January 2012 to 31st May 2020 with acute VTE, and subsequently initiated on anticoagulation treatment with either DOAC or VKA (warfarin). Univariate and bivariate analyses were used to evaluate differences in demographics by treatment type and BMI. Multivariate Cox proportional hazard regression was used to assess the risk of VTE recurrence by type of treatment among morbidly obese patient subgroup. Results: There were 247 (11.8%) morbidly obese (≥ 40 kg/m2) patients who were more likely than non-obese patients to be younger, female, and of non-white race. Thirty percent of the study population (n=74) had a BMI >50 kg/m2. T ime-to-event analysis confirmed that the hazard of experiencing a recurrent thrombosis was not statistically significantly different among morbidly obese patients treated with a DOAC compared with VKA (hazard ratio [HR]: 0.28, confidence interval [CI] 0.07-1.11, p = 0.07). Conclusions: This study aligns with previous literature and confirms that morbidly obese patients receiving DOAC or VKA have similar risks of recurrent VTE.

Surveillance of Antidepressant Safety (SADS): Active Signal Detection of Serious Medical Events Following SSRI and SNRI Initiation Using Big Healthcare Data

Introduction

The current process for generating evidence in pharmacovigilance has several limitations, which often lead to delays in the evaluation of drug-associated risks.

Objectives

In this study, we proposed and tested a near real-time epidemiological surveillance system using sequential, cumulative analyses focusing on the detection and preliminary risk quantification of potential safety signals following initiation of selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs).

Methods

We emulated an active surveillance system in an historical setting by conducting repeated annual cohort studies using nationwide Danish healthcare data (1996–2016). Outcomes were selected from the European Medicines Agency's Designated Medical Event list, summaries of product characteristics, and the literature. We followed patients for a maximum of 6 months from treatment initiation to the event of interest or censoring. We performed Cox regression analyses adjusted for standard sets of covariates. Potential safety signals were visualized using heat maps and cumulative hazard ratio (HR) plots over time.

Results

In the total study population, 969,667 new users were included and followed for 461,506 person-years. We detected potential safety signals with incidence rates as low as 0.9 per 10,000 person-years. Having eight different exposure drugs and 51 medical events, we identified 31 unique combinations of potential safety signals with a positive association to the event of interest in the exposed group. We proposed that these signals were designated for further evaluation once they appeared in a prospective setting. In total, 21 (67.7%) of these were not present in the current summaries of product characteristics.

Conclusion

The study demonstrated the feasibility of performing epidemiological surveillance using sequential, cumulative analyses. Larger populations are needed to evaluate rare events and infrequently used antidepressants.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40264-021-01110-x.

A Network Meta-Analysis Comparing Osteoporotic Fracture among Different Direct Oral Anticoagulants and Vitamin K Antagonists in Patients with Atrial Fibrillation

Background

There are limited studies comparing the risk of osteoporosis and fractures between different direct oral anticoagulants (DOACs) and vitamin K antagonists (VKA) in non-valvular atrial fibrillation (AF). Using a network meta-analysis (NMA), we compared osteoporotic fractures among 5 different treatment arms, viz. dabigatran, rivaroxaban, apixaban, edoxaban, and VKA.

Methods

Ten studies, including 5 randomized control trials and 5 population-based studies, with a total of 321,844 patients (148,751 and 173,093 in the VKA and DOAC group, respectively) with a median follow-up of 2 years, were included. A Bayesian random-effects NMA model comparing fractures among the treatment arms was performed using MetInsight V3. Sensitivity analysis excluded studies with the highest residual deviances from the NMA model.

Results

The mean age of the patients was 70 years. The meta-analysis favored DOACs over VKA with significantly lower osteoporotic fracture (odds ratio [OR], 0.77; 95% credible interval [CrI], 0.70–0.86). The NMA demonstrated that fractures were significantly lower with apixaban compared with dabigatran (OR, 0.64; 95% CrI, 0.44–0.95); however, fractures were statistically similar between apixaban and rivaroxaban (OR, 0.84; 95% CrI, 0.58–1.24) and dabigatran and rivaroxaban (OR, 1.32; 95% CrI, 0.90–1.87). Based on the Bayesian model of NMA, the probability of osteoporotic fracture was highest with VKA and lowest with apixaban, followed by rivaroxaban, edoxaban, and dabigatran.

Conclusions

The decision to prescribe anticoagulants in elderly patients with AF should be made not only based on thrombotic and bleeding risks but also on the risk of osteoporotic fracture; these factors should be considered and incorporated in contemporary cardiology practice.

Cost-Effectiveness of Direct Non-Vitamin K Oral Anticoagulants Versus Vitamin K Antagonists for the Management of Patients with Non-Valvular Atrial Fibrillation Based on Available "Real-World" Evidence: The Italian National Health System Perspective

BACKGROUND AND OBJECTIVE

The increasing availability of real-world evidence (RWE) about safety and effectiveness of direct non-vitamin K oral anticoagulants (DOACs) for the management of atrial fibrillation (AF) offers the opportunity to better understand the clinical and economic implications of DOACs versus vitamin K antagonists (VKAs). The objective of this study was to compare the economic implications of DOACs and VKAs using data from real-world evidence in patients with AF.

METHODS

A Markov model simulating the lifetime course of patients diagnosed with non-valvular AF was used to evaluate the cost-effectiveness of DOACs (i.e., rivaroxaban, dabigatran and apixaban) versus VKAs from the Italian National Health System (INHS) perspective. The model was made up of data from the literature and a meta-analysis of RWE on the incidence of stroke/systemic embolism (SE), major bleeding (MB), intracranial haemorrhage (ICH) and all-cause mortality (ACM); direct costs included drug costs, costs for drug monitoring, and management of events from official national lists. One-way and probabilistic sensitivity analyses (PSA) were used to assess the robustness of the results.

RESULTS

Results from the meta-analysis showed that apixaban had a high probability of being the most effective for stroke/SE, MB and ACM. Despite their higher acquisition costs, the cost-effectiveness analysis showed all DOACs involved a saving when compared with VKAs, with per-patient savings ranging between €4647 (rivaroxaban) to €6086 (apixaban). Moreover, all DOACs indicated a gain both in quality-adjusted life-years and life-years. According to PSA, findings related to apixaban were consistent, while for dabigatran and rivaroxaban PSA revealed a higher degree of uncertainty.

CONCLUSIONS

The beneficial effect of DOACs on containing events showed in RWE had the potential to offset drug-related costs, thus improving the sustainability of treatment for non-valvular AF in daily clinical practice.

Effects of Carbamazepine and Phenytoin on Pharmacokinetics and Pharmacodynamics of Rivaroxaban

Rivaroxaban (RIV) is commonly prescribed with carbamazepine or phenytoin (CBZ/PHT) in post-stroke seizure or post-stroke epilepsy patients. Although adverse events have been reported in several previous studies when they are coadministered, there are no studies of the interactions between these drugs. Therefore, our study was conducted to solve this lack of information. The potential effects of CBZ/PHT were investigated by comparing the pharmacokinetic (PK) and pharmacodynamic (PD) parameters of RIV between the control group (RIV alone) and the test groups (RIV administered with CBZ/PHT) in rats using the noncompartmental analysis (NCA) and the compartmental model approach. The NCA results indicate that AUC_t of RIV decreased by 57.9% or 89.7% and C_max of RIV decreased by 43.3% or 70.0% after administration of CBZ/PHT, respectively. In addition, both CBZ and PHT generally reduced the effects of RIV on the prothrombin times of the blood samples. PK profiles of RIV were most properly described by a two-compartment disposition model with a mixed first- and zero-order absorption kinetics and a first-order elimination kinetics. The compartmental model approach showed that a 211% or 1030% increase in CL/F of RIV and a 33.9% or 43.4% increase in D2 of RIV were observed in the test groups by the effects of CBZ/PHT, respectively. In conclusion, CBZ and PHT significantly reduced RIV exposure and therefore reduced the therapeutic effects of RIV. Consequently, this might result in adverse events due to insufficient RIV concentration to attain its therapeutic effects. Further studies are needed to validate this finding.

Risk of Major Gastrointestinal Bleeding With New vs Conventional Oral Anticoagulants: A Systematic Review and Meta-analysis

BACKGROUND & AIMS

There is controversy over whether use of non-vitamin K antagonist oral anticoagulants (NOACs) associates with increased risk of major gastrointestinal bleeding (GIB) compared with conventional therapies (such as vitamin K antagonists or anti-platelet agents). We performed a systematic review and meta-analysis of data from randomized controlled trials and high-quality real-world studies.

METHODS

We performed a systematic search of the MEDLINE, EMBASE, Cochrane Library, and ClinicalTrials.gov Website databases (through Oct 12, 2018) for randomized controlled trials and high-quality real-world studies that reported major GIB events in patients given NOACs or conventional therapy. Relative risks (RRs) for randomized controlled trials and adjusted hazard ratios (aHRs) for real-world studies were calculated separately using random-effects models.

RESULTS

We analyzed data from 43 randomized controlled trials (183,752 patients) and 41 real-world studies (1,879,428 patients). The pooled major rates of GIB for patients on NOACs (1.19%) vs conventional treatment (0.92%) did not differ significantly (RR from randomized controlled trials, 1.09; 95% CI, 0.91-1.31 and aHR from real-world studies, 1.02; 95% CI, 0.94-1.10; P_interaction=.52). Rivaroxaban, but not other NOACs, was associated with an increased risk for major GIB (RR from randomized controlled trials, 1.39; 95% CI, 1.17-1.65 and aHR from real-world studies, 1.14; 95% CI, 1.04-1.23; P_interaction = .06). Analyses of subgroups, such as patients with different indications, dosage, or follow-up time, did not significantly affect results. Meta-regression analysis failed to detect any potential confounding to impact the primacy outcome.

CONCLUSIONS

In a systematic review and meta-analysis of data from randomized controlled trials and real-world studies, we confirmed that there is no significant difference in risk of major GIB between patients receiving NOACs vs conventional treatment. Rivaroxaban users had a 39% increase in risk for major GIB.

The EMPagliflozin compaRative effectIveness and SafEty (EMPRISE) study programme: Design and exposure accrual for an evaluation of empagliflozin in routine clinical care

BACKGROUND

The EMPA-REG OUTCOME trial showed that empagliflozin reduced the risk of cardiovascular death and hospitalization for heart failure (HHF) in diabetic patients with cardiovascular disease. EMPRISE is a study programme on the effectiveness, safety and healthcare utilization of empagliflozin in routine care, leveraging real-world data from two commercial and one federal US data sources from 2014 to 2019.

OBJECTIVES

To describe rationale and design of EMPRISE, assess ability to minimize confounding and evaluate the time to reach sufficient statistical power for a key study outcome, HHF, using baseline information from the first year of EMPRISE.

METHODS

In 3 claims data sets, we identified a 1:1 propensity score (PS)-matched cohort of diabetic patients ≥18 years initiating empagliflozin or a dipeptidyl peptidase-4 inhibitor (DPP4i), resulting in 6643 total pairs. The PS model included >140 baseline covariates. We measured covariate balance via standardized differences (SD) and postmatching c-statistic. We computed the incidence rate (IR) of HHF, predicted exposure accrual over time and calculated expected power.

RESULTS

After PS matching, patient characteristics were balanced with SD <0.1 and c-statistic between 0.54 and 0.59. The population IR of HHF was 4.4 per 1000 person-years using a specific HHF definition and 14.8 using a broader HHF definition. In our projection, 80%-powered analyses would require a minimum of 169 HHF events, expected to accumulate by year 3 (specific definition) or year 2 (broader definition).

CONCLUSION

Baseline information from EMPRISE provided evidence of solid confounding control and adequate exposure accrual with expected powered analyses for the primary outcomes.

Cardiovascular safety of linagliptin compared with other oral glucose-lowering agents in patients with type 2 diabetes: A sequential monitoring programme in routine care

AIM

To evaluate the safety of linagliptin versus other glucose-lowering medications in a multi-year monitoring programme using insurance claims data.

METHODS

In two commercial US claims databases, we identified three pairwise 1:1 propensity-score (PS)-matched cohorts of patients with type 2 diabetes (T2D) aged ≥18 years initiating linagliptin or a comparator (other dipeptidyl peptidase-4 [DPP-4] inhibitors [n = 31 492 pairs], pioglitazone [n = 23 316 pairs], or second-generation sulphonylureas [n = 19 731 pairs]) between May 2011 and December 2015. The primary endpoint was the risk of a composite cardiovascular (CV) outcome (hospitalization for myocardial infarction, stroke, unstable angina, or coronary revascularization). We estimated pooled hazard ratios (HRs) and 95% confidence intervals (CIs), controlling for >100 baseline characteristics.

RESULTS

Patient characteristics were well balanced after PS-matching. The mean age was 55 years and mean follow-up was 0.8 years. Linagliptin conferred a similar risk of the composite CV outcome compared to other DPP-4 inhibitors (HR 0.91, 95% CI 0.79-1.05) and pioglitazone (HR 0.98, 95% CI 0.84-1.15), and showed a reduced risk of CV outcomes compared to second-generation sulphonylureas (HR 0.76, 95% CI 0.64--0.92). Key findings were signalled at the first interim analysis in June 2013 and solidified during ongoing monitoring until 2015.

CONCLUSION

Analyses from a large monitoring programme in routine care of patients with T2D, showed that linagliptin had similar CV safety compared to other DPP-4 inhibitors and pioglitazone, and a reduced CV risk compared to sulphonylureas.