Sequential Monitoring of the Comparative Effectiveness and Safety of Dabigatran in Routine Care

Sequential Epidemiological Analyses of Real-World Data: A Tool for Prospective Drug Safety Surveillance from the Rofecoxib Example

INTRODUCTION

Large administrative healthcare databases can be used for near real-time sequential safety surveillance of drugs as an alternative approach to traditional reporting-based pharmacovigilance. The study aims to build and empirically test a prospective drug safety monitoring setup and perform a sequential safety monitoring of rofecoxib use and risk of cardiovascular outcomes.

METHODS

We used Danish population-based health registers and performed sequential analysis of rofecoxib use and cardiovascular outcomes using case-time-control and cohort study designs from January 2000 to September 2004. Each monitoring period added 6 months of data until the end of the study period. In the case-time-control study, incident cases of myocardial infarction (MI) and ischemic stroke were identified and matched with up to five time controls on age, sex, and calendar time. Exposure status on the date of diagnosis was assessed using a 60-day focal window, with reference windows 120, 180, and 240 days prior to the diagnoses. In the cohort study, incident users of rofecoxib were matched up to 1:4 with ibuprofen users (active comparators) using high-dimensional disease risk scores and were followed for 60 days.

RESULTS

The earliest association between rofecoxib use and the risk of MI was seen in study period 2 for case-time-control design (OR 1.42, 95% CI 1.04-1.93) and in study period 7 for the cohort study design (RR 1.22; 95% CI 1.02-1.47).

CONCLUSIONS

Our prospective drug safety monitoring setup showed that the risk of MI could have been detected 3.5 years before the ultimate market withdrawal of rofecoxib. However, further research is needed to validate this approach.

Enhancing External Control Arm Analyses through Data Calibration and Hybrid Designs

Almost all external control arm analyses to contextualize findings of a single arm trial struggle with two key issues: the lack of baseline randomization, and equally important, the difference in data collection between the experimental arm with its primary data collection, and the external control arm using secondary data. We illustrate the data calibration design to remedy issues arising from differential measurements in the two arms, and discuss the hybrid design that expands an underpowered randomized internal control arm with real-world data to mitigate the lack of randomization of the external control arm. We show how the two approaches fit into an evidence-development strategy that naturally builds on the incremental insights gained.

A Scalable Approach to Assess the Safety of Recently Marketed Systemic Treatments for Atopic Dermatitis in Clinical Practice: First Analysis Cycle of a Sequential Monitoring System

Targeted systemic immune-modulating drugs to treat atopic dermatitis were highly efficacious in randomized trials. Trials with limited number of subjects leave questions about their safety. We describe a data and analytics structure for the production of timely, high-quality evidence on the comparative safety of recently approved immune-modulating drugs in patients with atopic dermatitis in clinical practice. We established a series of sequential propensity score-balanced cohorts that grow in size with each annual data refresh. Nine health outcomes of interest plus conjunctivitis as a positive tracer outcome were identified. The initial treatment comparison was dupilumab, an IL-4/13 inhibitor, or tralokinumab, an IL-13 inhibitor, versus abrocitinib/upadacitinib, both Jak inhibitors. The first analysis cycle (December 2021-February 2023) compared 269 patients initiating Jak inhibitors and 2650 initiating IL-4/IL-13 inhibitors. Patient characteristics were well-balanced after propensity score matching. Outpatient infections within 180 days occurred in 18% of Jak1 inhibitor initiators versus 12% of dupilumab/tralokinumab initiators (risk ratio = 1.50, 95% confidence interval = 0.96-2.33), whereas acne risks were 7 versus 3%, respectively (risk ratio = 2.29, 95% confidence interval = 0.96-5.46). This sequential monitoring system will produce essential knowledge on the safety of immune-modulating drugs to treat atopic dermatitis on the basis of its growing study size of patients observed in clinical practice.

Assessing the Benefits and Harms of Pharmacotherapy in Older Adults with Frailty: Insights from Pharmacoepidemiologic Studies of Routine Health Care Data

The objective of this review is to summarize and appraise the research methodology, emerging findings, and future directions in pharmacoepidemiologic studies assessing the benefits and harms of pharmacotherapies in older adults with different levels of frailty. Older adults living with frailty are at elevated risk for poor health outcomes and adverse effects from pharmacotherapy. However, current evidence is limited due to the under-enrollment of frail older adults and the lack of validated frailty assessments in clinical trials. Recent advancements in measuring frailty in administrative claims and electronic health records (database-derived frailty scores) have enabled researchers to identify patients with frailty and to evaluate the heterogeneity of treatment effects by patients' frailty levels using routine health care data. When selecting a database-derived frailty score, researchers must consider the type of data (e.g., different coding systems), the length of the predictor assessment period, the extent of validation against clinically validated frailty measures, and the possibility of surveillance bias arising from unequal access to care. We reviewed 13 pharmacoepidemiologic studies published on PubMed from 2013 to 2023 that evaluated the benefits and harms of cardiovascular medications, diabetes medications, anti-neoplastic agents, antipsychotic medications, and vaccines by frailty levels. These studies suggest that, while greater frailty is positively associated with adverse treatment outcomes, older adults with frailty can still benefit from pharmacotherapy. Therefore, we recommend routine frailty subgroup analyses in pharmacoepidemiologic studies. Despite data and design limitations, the findings from such studies may be informative to tailor pharmacotherapy for older adults across the frailty spectrum.

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.

Durability of the Single-Dose Ad26.COV2.S Vaccine in the Prevention of COVID-19 Infections and Hospitalizations in the US Before and During the Delta Variant Surge

IMPORTANCE

Vaccination against the SARS-CoV-2 virus is critical to control the pandemic. Randomized clinical trials demonstrated efficacy of the single-dose Ad26.COV2.S COVID-19 vaccine, but data on longer-term protection in clinical practice and effectiveness against variants are needed.

OBJECTIVE

To assess the association between receiving the Ad26.COV2.S vaccine and COVID-19-related infections and hospitalizations before and during the Delta variant surge.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included adults aged 18 years and older who were newly Ad26.COV2.S-vaccinated matched to as many as 10 unvaccinated individuals by date, location, age, sex, and comorbidity index. This was followed by 1:4 propensity score matching on COVID-19 risk factors. Data were collected from US insurance claims data from March 1, 2020, through August 31, 2021.

EXPOSURES

Vaccination with Ad26.COV2.S vs no vaccination.

MAIN OUTCOMES AND MEASURES

Vaccine effectiveness (VE) was estimated for recorded COVID-19 infection and COVID-19-related hospitalization, nationwide and in subgroups by age, high-risk factors, calendar time, and states with high incidences of the Delta variant. VE estimates were corrected for underrecording of vaccinations in insurance data.

RESULTS

Among 422 034 vaccinated individuals (mean [SD] age, 54.7 [17.4] years; 236 437 [56.0%] women) and 1 645 397 matched unvaccinated individuals (mean [SD] age, 54.5 [17.5] years; 922 937 [56.1%] women), VE was 76% (95% CI, 75%-77%) for COVID-19 infections and 81% (95% CI, 78%-82%) for COVID-19-related hospitalizations. VE was stable for at least 180 days after vaccination and over calendar time. Among states with high Delta variant incidence, VE during June to August 2021 was 74% (95% CI, 71%-77%) for infections and 81% (95% CI, 75%-86%) for hospitalizations. VE for COVID-19 was higher in individuals younger than 65 years (78%; 95% CI, 77%-79%) and lower in immunocompromised patients (64%; 95% CI, 59%-68%). All estimates were corrected for vaccination underrecording; uncorrected VE, which served as a lower bound, was 66% (95% CI, 64%-67%) for any recorded COVID-19 infection and 72% (95% CI, 69%-74%) for COVID-19-related hospitalization.

CONCLUSIONS AND RELEVANCE

This cohort study in US clinical practice showed stable VE of Ad26.COV2.S for at least 6 months before as well as during the time the Delta variant emerged and became dominant.

Key Characteristics of Database Studies on Drug Effectiveness in the Postmarketing Stage: A Systematic Review

BACKGROUND

In recent years, real-world data (RWD) have been actively used in the field of pharmaceutical research. Database (DB) study, one of the observational studies using RWD, is a comprehensive, continuous, and rapid research method that plays an important role in the postmarketing stage of drugs, although the interpretation of the results may be limited. DB studies are often focused on drug safety, and previous research reviewing DB studies on drug effectiveness across different disease areas have been limited.

OBJECTIVE

The objective of this review was to reveal the current status of DB studies on drug effectiveness in various therapeutic areas and to provide information that allows researchers to consider conducting appropriate DB studies on drug effectiveness in the postmarketing stage.

METHODS

For this systematic review, we searched Embase and MEDLINE for DB studies on drug effectiveness published between 1 January 2018 and 31 December 2019. We reviewed the title, abstract, and methods to identify studies on drug effectiveness using medical information DBs, and excluded non-medical studies, studies on non-drug, and studies on drug safety, actual use, or cost outcomes that did not include any effectiveness outcomes. The name and type of the DB (administrative claims DB, clinical DB, pharmacy DB, and DB linkage), study design, comparison group, type of outcome, and presence or absence of reference to the outcome definition were extracted and summarized according to disease areas.

RESULTS

We obtained 225 articles on DB studies on drug effectiveness using DBs that integrate large-scale medical data for secondary use across different disease areas. Among the DB classifications, administrative claims DBs (70%, 158/225) were most commonly used, while pharmacy DBs were used in only three studies. The largest number of reported studies were associated with cardiovascular, respiratory, and infectious diseases. Outcomes were often inpatient diagnosis, and some ideas included defining effectiveness based on drug use. While various outcomes were uniformly used in studies for the treatment of infectious diseases and respiratory organs, death (overall survival [OS]) and drug continuation (progression-free survival [PFS]) in patients with cancer, laboratory values in the endocrine system (mainly diabetes) were used as the main outcomes. Outcome validation within the article was limited. New user design (32%, 73/225), propensity score analysis (58%, 131/225), and sensitivity analysis (40%, 90/225) were used as measures to reduce bias in these studies. Sixty-eight studies (30%, 68/225) were supported by pharmaceutical companies.

CONCLUSIONS

This systematic review summarized the status of cross-disease research articles on DB studies on drug effectiveness. While considering the strengths and limitations of DB studies, we hope that our comprehensive results would help to promote appropriate DB studies on drug effectiveness in the postmarketing stage.

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.

Evaluating utilization patterns of oral anticoagulants in routine care

Essentials Unlike warfarin, treatment with DOACs do not require regular plasma level monitoring. We compared persistence of patients treated with DOACs compared to warfarin. Persistence at 12 months was higher for all DOACs compared to warfarin. Persistence to anticoagulant therapy was generally poor in commercially insured patients.

BACKGROUND

Direct oral anticoagulants (DOACs) were developed as an alternative to vitamin K antagonists for a variety of indications. Unlike warfarin, DOACs do not require regular plasma level monitoring.

OBJECTIVE

We investigated whether this simplification in management affects persistence on DOACs vs warfarin.

METHODS

Within two US commercial health insurance databases (MarketScan and Clinformatics™ DataMart), we compared baseline characteristics and evaluated rates of nonpersistence (≥30-day treatment gap or switching) among patients with nonvalvular atrial fibrillation who initiated an oral anticoagulant between October 2010 and September 2015.

RESULTS

In the larger of the two data sources (MarketScan), we identified 166 690 anticoagulant initiators during the study period. After propensity score (PS) matching, 24 141 dabigatran initiators, 26 066 rivaroxaban, and 12 578 apixaban initiators were included along with the 1:1 matched warfarin initiators. The proportion of patients who were nonpersistent after 12 months was lower for DOAC users (dabigatran 66%, rivaroxaban 60%, apixaban 53%) compared with warfarin users (72%). The same relative ranking was observed in direct comparisons among the DOACs after PS-matching. Findings in Clinformatics DataMart were similar.

CONCLUSION

Results from this long-term surveillance program showed that patients who initiated DOACs were more likely to be persistent to therapy compared with those who initiated warfarin. Persistence to anticoagulant therapy was generally poor in commercially insured patients.