Information-based group sequential design for post-market safety monitoring of medical products using real world data.

Real world healthcare data are commonly used in post-market safety monitoring studies to address potential safety issues related to newly approved medical products. Such studies typically involve repeated evaluations of accumulating safety data with respect to pre-defined hypotheses, for which the group sequential design provides a rigorous and flexible statistical framework. A major challenge in designing a group sequential safety monitoring study is the uncertainty associated with product uptake, which makes it difficult to specify the final sample size or maximum duration of the study. To deal with this challenge, we propose an information-based group sequential design which specifies a target amount of information that would produce adequate power for detecting a clinically significant effect size. At each interim analysis, the variance estimate for the treatment effect of interest is used to compute the current information time, and a pre-specified alpha spending function is used to determine the stopping boundary. The proposed design can be applied to regression models that adjust for potential confounders and/or heterogeneous treatment exposure. Simulation results demonstrate that the proposed design performs reasonably well in realistic settings.

Predicting the immediate impact of national lockdown on neovascular age-related macular degeneration and associated visual morbidity: an INSIGHT Health Data Research Hub for Eye Health report.

OBJECTIVE: Predicting the impact of neovascular age-related macular degeneration (nAMD) service disruption on visual outcomes following national lockdown in the UK to contain SARS-CoV-2. METHODS AND ANALYSIS: This retrospective cohort study includes deidentified data from 2229 UK patients from the INSIGHT Health Data Research digital hub. We forecasted the number of treatment-naïve nAMD patients requiring anti-vascular endothelial growth factor (anti-VEGF) initiation during UK lockdown (16 March 2020 through 31 July 2020) at Moorfields Eye Hospital (MEH) and University Hospitals Birmingham (UHB). Best-measured visual acuity (VA) changes without anti-VEGF therapy were predicted using post hoc analysis of Minimally Classic/Occult Trial of the Anti-VEGF Antibody Ranibizumab in the Treatment of Neovascular AMD trial sham-control arm data (n=238). RESULTS: At our centres, 376 patients were predicted to require anti-VEGF initiation during lockdown (MEH: 325; UHB: 51). Without treatment, mean VA was projected to decline after 12 months. The proportion of eyes in the MEH cohort predicted to maintain the key positive visual outcome of ≥70 ETDRS letters (Snellen equivalent 6/12) fell from 25.5% at baseline to 5.8% at 12 months (UHB: 9.8%-7.8%). Similarly, eyes with VA <25 ETDRS letters (6/96) were predicted to increase from 4.3% to 14.2% at MEH (UHB: 5.9%-7.8%) after 12 months without treatment. CONCLUSIONS: Here, we demonstrate how combining data from a recently founded national digital health data repository with historical industry-funded clinical trial data can enhance predictive modelling in nAMD. The demonstrated detrimental effects of prolonged treatment delay should incentivise healthcare providers to support nAMD patients accessing care in safe environments. TRIAL REGISTRATION NUMBER: NCT00056836.

Serious Infection Rates Among Patients with Select Autoimmune Conditions: A Claims-Based Retrospective Cohort Study from Taiwan and the USA.

INTRODUCTION: Serious infections are an important concern for patients with autoimmune conditions. We sought to estimate serious infection rates among patients with select autoimmune conditions relative to the general population in Taiwan and the USA. METHODS: This retrospective cohort study estimated setting-specific standardized serious infection incidence rates and ratios among patients with systemic lupus erythematosus, including extra-renal lupus and lupus nephritis, rheumatoid arthritis and primary membranous nephropathy, compared with the general population using insurance claims for hospitalizations between 2000 and 2013. Multivariable Cox proportional hazard models were used to estimate adjusted hazard ratios for serious infections, adjusting for age, sex, index year, prior serious infection, comorbidities and medications. RESULTS: In Taiwan, serious infection rates were 22.7, 28.7, 70.6, 43.4 and 215.3 per 1000 person-years among the general population and among cohorts of patients with primary membranous nephropathy, rheumatoid arthritis, extra-renal lupus and lupus nephritis, respectively. In the USA, serious infection rates were 2.6, 9.0, 15.6, 21.0 and 63.3 per 1000 person-years among the general population and among cohorts of patients with primary membranous nephropathy, rheumatoid arthritis, extra-renal lupus and lupus nephritis, respectively. Patients had significantly higher serious infection rates than the general population in both settings, largely driven by bacterial, respiratory, urinary tract and opportunistic infections. Patients with lupus nephritis had the highest burden of serious infections relative to the general population, with 7- to 25-fold higher adjusted hazard ratios in Taiwan and the USA, respectively. CONCLUSION: This study identified a significant excess serious infection burden among patients with targeted autoimmune conditions compared with the general populations in Taiwan and the USA.

Development and evaluation of a proxy for baseline ECOG PS in advanced non-small cell lung cancer, bladder cancer, and melanoma: An electronic health record study.

PURPOSE: Eastern Cooperative Oncology Group performance status (ECOG PS) is an important predictor for receipt of treatment and overall survival (OS) but is often unreported in routine care. We developed a proxy for baseline ECOG PS using electronic health records (EHRs). METHODS: We analyzed patients who were diagnosed with advanced non-small cell lung cancer (aNSCLC), advanced bladder cancer (aBCa), and advanced melanoma (aMEL) between 2011 and 2018 and had a baseline (reported between diagnosis and treatment) ECOG PS in a real-world database. We used stepwise multivariable logistic regression to model associations between baseline ECOG PS good (<2) versus poor (≥2) and sociodemographic, clinical, and laboratory measures in each cancer type. Predictive accuracy of classifying ECOG PS was assessed. We tested the association between OS and observed and predicted ECOG PS. RESULTS: In total, 20 697 aNSCLC patients, 2627 aBCa patients, and 2558 aMEL patients constituted the study population. Percentage of patients with poor ECOG PS ranged from 15.3% (aMEL) to 28.5% (aNSCLC). Poor ECOG PS was associated with more comorbid conditions, older age, lower body mass index, metastases, and abnormal laboratory indicators. Overall prediction accuracy using a 0.50 cutpoint was 73.3% for NSCLC, 73.8% for aBCa, and 85.4% for aMEL. The association of OS with ECOG PS was consistent between the observed and proxy measures. CONCLUSIONS: In the EHR-derived data, clinical, sociodemographic, and laboratory information were used to assign ECOG PS and enhance the use of real-world data in outcome studies.

Increased Bacillus Calmette-Guérin Treatment Intensity Associated With Improved Outcomes in Elderly Patients With Non-Muscle-invasive Bladder Cancer in United States Clinical Practice.

OBJECTIVE: To characterize Bacillus Calmette-Guérin (BCG) treatment patterns and associated outcomes in a large cohort of patients with non-muscle-invasive bladder cancer (NMIBC). METHODS: Our retrospective analysis of patients aged ≥66 years with stage 0-1 urothelial bladder carcinoma diagnosed between 2000 and 2012 in the United States Surveillance, Epidemiology, and End Results-Medicare database estimated proxies for recurrence and secondary events and both all-cause and bladder cancer-specific mortality. Proportional hazards models were used in conditional landmark analyses to compare adequate (≥5 induction instillations and ≥2 maintenance instillations) and inadequate BCG, stratified by National Comprehensive Cancer Network risk group. RESULTS: Of 39,532 patients who met the selection criteria, 16,225 (41.0%) received BCG; of them, 4602 (28.4%; 11.6% overall) received adequate treatment. Adequately treated patients were slightly younger and healthier than inadequately treated patients. Half of patients with intermediate- and high-risk NMIBC did not receive BCG; few received adequate treatment. At the 12-month landmark, adequate BCG treatment was associated with decreased risks of recurrence and of cancer-specific and all-cause mortality in patients with intermediate- and high-risk disease. CONCLUSION: We observed lower than expected use of adequate BCG treatment in patients with intermediate- to high-risk NMIBC despite evidence of improved outcomes, which suggested that practice patterns may not be in line with management recommendations in this population.

Community Characteristics Associated With Seeking Medical Evaluation for Suspected Child Sexual Abuse in Greater Houston.

Child sexual abuse (CSA) affects over 62,000 children annually in the United States. A primary obstacle to the success of a public health prevention strategy is the lack of knowledge around community level risk factors for CSA. We evaluated community level characteristics for children seeking care for suspected CSA in the Greater Houston area for 2009. There was a total incidence rate of medical evaluations for suspected CSA of 5.9/1000 children. We abstracted the medical charts of 1982 (86 %) children who sought a medical evaluation for suspected CSA at three main medical systems in the Greater Houston area for 2009. We evaluated 18 community level variables from the American Community Survey for the 396 zip codes these children lived in. The mean number of cases per Greater Houston zip code was 2.77 (range 0-27), with 62 % of zip codes not having a case at any of the three sites surveyed. Zip codes with a higher than Houston average rate of vacant houses, never married females and unemployed labor force with high family poverty rate, were associated with an increased rate of children seeking care for suspected CSA. We demonstrated zip codes level characteristics which were associated with an increased rate of children seeking care for suspected CSA. Our modelling process and our data have implications for community based strategies aimed at improved surveillance or prevention of CSA. The process of identifying locally specific community level factors suggests target areas which have particular socioeconomic characteristics which are associated with increased rate of seeking CSA evaluations.