Cautionary note on regional consistency evaluation in multiregional clinical trials with binary outcomes.

Multiregional clinical trials (MRCTs) have become increasingly common during the development of new drugs to obtain simultaneous drug approvals worldwide. When planning MRCTs, a major statistical challenge is determination of the regional sample size. In general, the regional sample size must be determined as the sample size such that the regional consistency probability, defined as the probability of meeting the regional consistency criterion, is greater than a prespecified value. The Japanese Ministry of Health, Labour and Welfare proposed two criteria for regional consistency. Moreover, many researchers have proposed corresponding closed-form formulas for calculating regional consistency probabilities when the primary outcome is continuous. Although some researchers have argued that those formulas are also applicable to cases with binary outcomes, it remains questionable whether such an argument can be true. Based on simulation results, we demonstrate that the existing formulas are inappropriate for binary cases, even when the regional sample size is sufficiently large. To address this issue, we develop alternative formulas and use simulation to show that they provide accurate regional consistency probabilities. Furthermore, we present an application of our proposed formulas for an MRCT of advanced or metastatic clear-cell renal cell carcinoma.

Tratamientos modificadores de la enfermedad en pacientes con esclerosis múltiple en España / Disease-modifying treatments for patients with multiple sclerosis in Spain

La esclerosis múltiple es una enfermedad desmielinizante crónica del sistema nervioso central y discapacitante a largo plazo. Existen diferentes tratamientos modificadores de la enfermedad. Estos pacientes, a pesar de ser generalmente jóvenes, tienen una elevada comorbilidad y riesgo de polimedicación por su compleja sintomatología y discapacidad. Objetivo principal determinar el tipo de tratamiento modificador de la enfermedad en los pacientes atendidos en servicios de farmacia de hospitales españoles. Objetivos secundarios Conocer los tratamientos concomitantes, determinar la prevalencia de la polifarmacia, identificar la prevalencia de interacciones y analizar la complejidad farmacoterapéutica. Método estudio observacional, transversal y multicéntrico. Se incluyeron todos los pacientes con diagnóstico de esclerosis múltiple y tratamiento modificador de la enfermedad activo a los que se atendió en las consultas de pacientes externos o en los hospitales de día durante la segunda semana de febrero 2021. Se recogieron: el tratamiento modificador, las comorbilidades y los tratamientos concomitantes para determinar el patrón de multimorbilidad, polifarmacia, complejidad farmacoterapéutica (Medication Regimen Complexity Index) e interacciones medicamentosas. Resultados se incluyeron 1.407 pacientes de 57 centros de 15 Comunidades Autónomas. La forma de presentación de la enfermedad más frecuente fue la forma remitente recurrente (89,3%). El tratamiento modificador de la enfermedad más prescrito fue dimetilfumarato (19,1%), seguido de teriflunomida (14,0%). De los tratamientos modificadores parenterales, los 2 más prescritos fueron el acetato de glatiramero y el natalizumab con un 11,1 y 10,8% respectivamente. El 24,7% de los pacientes tenían una comorbilidad y el 39,8% al menos 2 comorbilidades. El 13,3% pertenecía al menos a uno de los patrones definidos de multimorbilidad y el 16,5% pertenecían a 2 o más patrones. ... (AU)

Multiple sclerosis is a chronic demyelinating disease of the central nervous system and long-term disabling. Different disease-modifying treatments are available. These patients, despite being generally young, have high comorbidity and risk of polymedication due to their complex symptomatology and disability.Objective primaryTo determine the type of disease-modifying treatment in patients seen in Spanish hospital pharmacy departments.Secondary objectivesTo determine concomitant treatments, determine the prevalence of polypharmacy, identify the prevalence of interactions and analyse pharmacotherapeutic complexity.MethodObservational, cross-sectional, multicentre study. All patients with a diagnosis of multiple sclerosis and active disease-modifying treatment who were seen in outpatient clinics or day hospitals during the second week of February 2021 were included. Modifying treatment, comorbidities and concomitant treatments were collected to determine multimorbidity pattern, polypharmacy, pharmacotherapeutic complexity (Medication Regimen Complexity Index) and drug-drug interactions.Results1,407 patients from 57 centres in 15 autonomous communities were included. The most frequent form of disease presentation was the relapsing remitting form (89.3%). The most prescribed disease-modifying treatment was dimethyl fumarate (19.1%), followed by teriflunomide (14.0%). Of the parenteral disease-modifying treatments, the two most prescribed were glatiramer acetate and natalizumab with 11.1% and 10.8%. 24.7% of the patients had one comorbidity and 39.8% had at least 2 comorbidities. 13.3% belonged to at least one of the defined patterns of multimorbidity and 16.5% belonged to 2 or more patterns. The concomitant treatments prescribed were psychotropic drugs (35.5%); antiepileptic drugs (13.9%) and antihypertensive drugs and drugs for cardiovascular pathologies (12.4%). ... (AU)

Predicting alcohol dependence from multi-site brain structural measures.

To identify neuroimaging biomarkers of alcohol dependence (AD) from structural magnetic resonance imaging, it may be useful to develop classification models that are explicitly generalizable to unseen sites and populations. This problem was explored in a mega-analysis of previously published datasets from 2,034 AD and comparison participants spanning 27 sites curated by the ENIGMA Addiction Working Group. Data were grouped into a training set used for internal validation including 1,652 participants (692 AD, 24 sites), and a test set used for external validation with 382 participants (146 AD, 3 sites). An exploratory data analysis was first conducted, followed by an evolutionary search based feature selection to site generalizable and high performing subsets of brain measurements. Exploratory data analysis revealed that inclusion of case- and control-only sites led to the inadvertent learning of site-effects. Cross validation methods that do not properly account for site can drastically overestimate results. Evolutionary-based feature selection leveraging leave-one-site-out cross-validation, to combat unintentional learning, identified cortical thickness in the left superior frontal gyrus and right lateral orbitofrontal cortex, cortical surface area in the right transverse temporal gyrus, and left putamen volume as final features. Ridge regression restricted to these features yielded a test-set area under the receiver operating characteristic curve of 0.768. These findings evaluate strategies for handling multi-site data with varied underlying class distributions and identify potential biomarkers for individuals with current AD.

Mega-analysis methods in ENIGMA: The experience of the generalized anxiety disorder working group.

The ENIGMA group on Generalized Anxiety Disorder (ENIGMA-Anxiety/GAD) is part of a broader effort to investigate anxiety disorders using imaging and genetic data across multiple sites worldwide. The group is actively conducting a mega-analysis of a large number of brain structural scans. In this process, the group was confronted with many methodological challenges related to study planning and implementation, between-country transfer of subject-level data, quality control of a considerable amount of imaging data, and choices related to statistical methods and efficient use of resources. This report summarizes the background information and rationale for the various methodological decisions, as well as the approach taken to implement them. The goal is to document the approach and help guide other research groups working with large brain imaging data sets as they develop their own analytic pipelines for mega-analyses.

Mitigating site effects in covariance for machine learning in neuroimaging data.

To acquire larger samples for answering complex questions in neuroscience, researchers have increasingly turned to multi-site neuroimaging studies. However, these studies are hindered by differences in images acquired across multiple sites. These effects have been shown to bias comparison between sites, mask biologically meaningful associations, and even introduce spurious associations. To address this, the field has focused on harmonizing data by removing site-related effects in the mean and variance of measurements. Contemporaneously with the increase in popularity of multi-center imaging, the use of machine learning (ML) in neuroimaging has also become commonplace. These approaches have been shown to provide improved sensitivity, specificity, and power due to their modeling the joint relationship across measurements in the brain. In this work, we demonstrate that methods for removing site effects in mean and variance may not be sufficient for ML. This stems from the fact that such methods fail to address how correlations between measurements can vary across sites. Data from the Alzheimer's Disease Neuroimaging Initiative is used to show that considerable differences in covariance exist across sites and that popular harmonization techniques do not address this issue. We then propose a novel harmonization method called Correcting Covariance Batch Effects (CovBat) that removes site effects in mean, variance, and covariance. We apply CovBat and show that within-site correlation matrices are successfully harmonized. Furthermore, we find that ML methods are unable to distinguish scanner manufacturer after our proposed harmonization is applied, and that the CovBat-harmonized data retain accurate prediction of disease group.

A Blueprint for the Conduct of Large, Multisite Trials in Telemedicine.

Recent literature supports the efficacy and efficiency of telemedicine in improving various health outcomes despite the wide variability in results. Understanding site-specific issues in the implementation of telemedicine trials for broader replication and generalizability of results is needed. Lessons can be learned from existing trials, and a blueprint can guide researchers to conduct these challenging studies using telemedicine more efficiently and effectively. This viewpoint presents relevant challenges and solutions for conducting multisite telemedicine trials using 7 ongoing and completed studies funded by the Patient-Centered Outcomes Research Institute portfolio of large multisite trials to highlight the challenges in implementing telemedicine trials. Critical issues of ensuring leadership and buy-in, appropriate funding, and diverse and representative trials are identified and described, as well as challenges related to clinical, informatics, regulatory, legal, quality, and billing. The lessons learned from these studies were used to create a blueprint of key aspects to consider for the design and implementation of multisite telemedicine trials.

Comparison of traveling-subject and ComBat harmonization methods for assessing structural brain characteristics.

Multisite magnetic resonance imaging (MRI) is increasingly used in clinical research and development. Measurement biases-caused by site differences in scanner/image-acquisition protocols-negatively influence the reliability and reproducibility of image-analysis methods. Harmonization can reduce bias and improve the reproducibility of multisite datasets. Herein, a traveling-subject (TS) dataset including 56 T1-weighted MRI scans of 20 healthy participants in three different MRI procedures-20, 19, and 17 subjects in Procedures 1, 2, and 3, respectively-was considered to compare the reproducibility of TS-GLM, ComBat, and TS-ComBat harmonization methods. The minimum participant count required for harmonization was determined, and the Cohen's d between different MRI procedures was evaluated as a measurement-bias indicator. The measurement-bias reduction realized with different methods was evaluated by comparing test-retest scans for 20 healthy participants. Moreover, the minimum subject count for harmonization was determined by comparing test-retest datasets. The results revealed that TS-GLM and TS-ComBat reduced measurement bias by up to 85 and 81.3%, respectively. Meanwhile, ComBat showed a reduction of only 59.0%. At least 6 TSs were required to harmonize data obtained from different MRI scanners, complying with the imaging protocol predetermined for multisite investigations and operated with similar scan parameters. The results indicate that TS-based harmonization outperforms ComBat for measurement-bias reduction and is optimal for MRI data in well-prepared multisite investigations. One drawback is the small sample size used, potentially limiting the applicability of ComBat. Investigation on the number of subjects needed for a large-scale study is an interesting future problem.

Microbleeds and clinical outcome in acute mild stroke patients treated with antiplatelet therapy: ADS post-hoc analysis.

BACKGROUND AND PURPOSE: In this post-hoc analysis using acute dual study dataset, the impacts of cerebral microbleeds (MBs) after mild stroke on clinical outcome were investigated. METHODS: The number of MBs on admission was categorized as 1) no MBs, 2) MBs 1-4, 3) MBs 5-9, and 4) MBs ≥ 10. The efficacy outcome was defined as neurological deterioration and stroke recurrence within 14 days. Safety outcomes included ICH and/or SAH as well as extracranial hemorrhages. RESULTS: Of the 1102 patients, 780 (71%) had no MBs on admission, while 230 (21%) had MBs 1-4, 48 (4%) had MBs 5-9, and 44 (4%) had MBs ≥ 10. The number of MBs was not associated with the neurological deterioration and/or stroke recurrence (p = 0.934), ICH and/or SAH (p = 0.743), and extracranial hemorrhage (p = 0.205). Favorable outcome was seem in 84% in the No MBs group, 83% in the MBs 1-4, 94% in the MBs 5-9, and 85% in the MBs ≥ 10 (p = 0.304). Combined cilostazol and aspirin therapy did not alter any rates of efficacy and safety outcomes among the no MBs, MBs 1-4, MBs 5-9, and MBs ≥ 10 groups compared to aspirin alone (all p > 0.05). By multivariate regression analysis, a history of ICH and diastolic blood pressure were the independent parameters to all of the MBs criteria (presence, MBs ≥ 5, and MBs ≥ 10). CONCLUSIONS: MBs did not alter the clinical outcome at 3 months of onset. Elevated diastolic blood pressure and a history of ICH were the essential parameters related to the MBs.

Cognitive Impairment and Dementia After Stroke: Design and Rationale for the DISCOVERY Study.

Stroke is a leading cause of the adult disability epidemic in the United States, with a major contribution from poststroke cognitive impairment and dementia (PSCID), the rates of which are disproportionally high among the health disparity populations. Despite the PSCID's overwhelming impact on public health, a knowledge gap exists with regard to the complex interaction between the acute stroke event and highly prevalent preexisting brain pathology related to cerebrovascular and Alzheimer disease or related dementia. Understanding the factors that modulate PSCID risk in relation to index stroke event is critically important for developing personalized prognostication of PSCID, targeted interventions to prevent it, and for informing future clinical trial design. The DISCOVERY study (Determinants of Incident Stroke Cognitive Outcomes and Vascular Effects on Recovery), a collaborative network of thirty clinical performance clinical sites with access to acute stroke populations and the expertise and capacity for systematic assessment of PSCID will address this critical challenge. DISCOVERY is a prospective, multicenter, observational, nested-cohort study of 8000 nondemented ischemic and hemorrhagic stroke patients enrolled at the time of index stroke and followed for a minimum of 2 years, with serial cognitive evaluations and assessments of functional outcome, with subsets undergoing research magnetic resonance imaging and positron emission tomography and comprehensive genetic/genomic and fluid biomarker testing. The overall scientific objective of this study is to elucidate mechanisms of brain resilience and susceptibility to PSCID in diverse US populations based on complex interplay between life-course exposure to multiple vascular risk factors, preexisting burden of microvascular and neurodegenerative pathology, the effect of strategic acute stroke lesions, and the mediating effect of genomic and epigenomic variation.

Common functional localizers to enhance NHP & cross-species neuroscience imaging research.

Functional localizers are invaluable as they can help define regions of interest, provide cross-study comparisons, and most importantly, allow for the aggregation and meta-analyses of data across studies and laboratories. To achieve these goals within the non-human primate (NHP) imaging community, there is a pressing need for the use of standardized and validated localizers that can be readily implemented across different groups. The goal of this paper is to provide an overview of the value of localizer protocols to imaging research and we describe a number of commonly used or novel localizers within NHPs, and keys to implement them across studies. As has been shown with the aggregation of resting-state imaging data in the original PRIME-DE submissions, we believe that the field is ready to apply the same initiative for task-based functional localizers in NHP imaging. By coming together to collect large datasets across research group, implementing the same functional localizers, and sharing the localizers and data via PRIME-DE, it is now possible to fully test their robustness, selectivity and specificity. To do this, we reviewed a number of common localizers and we created a repository of well-established localizer that are easily accessible and implemented through the PRIME-RE platform.

Use of endpoints in multiple myeloma randomized controlled trials over the last 15 years: A systematic review.

Surrogate endpoints are being used more frequently in randomized controlled trials, even though they do not consistently corelate with patient outcomes. We systemically evaluated the use of surrogate endpoints in multiple myeloma randomized controlled trials over the past 15 years. We searched three databases (Pubmed, Embase, Cochrane) for multiple myeloma randomized controlled trials from January 1, 2005 to December 30, 2019. The primary outcome of our study was the proportion of randomized controlled trials that used overall survival as their primary endpoint. Secondary outcomes included the use of surrogate endpoints, and trends over time, and whether they differed based on study sponsorship. We included 151 randomized controlled trials in our analysis. The primary endpoint was overall survival (OS) in 17 (11.3%) of studies, progression free survival (PFS) or event-defined endpoints in 91 studies (60.3%) and response-based endpoints in 44 studies (29.1%). Quality of life was a primary endpoint in only three studies (2%). The use of OS as a primary endpoint decreased from 28.5% of trials from 2005 to 2009 to 5.5% from 2015 to 2019. There has been a decrease in the clinically meaningful endpoint of OS over the past 15 years in multiple myeloma randomized controlled trials. Use of quality of life as a primary endpoint remains exceedingly low. It remains paramount to recognize that the use of surrogate endpoints is imperfect, and care based upon them requires constant physician and patient re-analysis.

Comparison of one-month versus twelve-month dual antiplatelet therapy after implantation of drug-eluting stents guided by either intravascular ultrasound or angiography in patients with acute coronary syndrome: rationale and design of prospective, multicenter, randomized, controlled IVUS-ACS and ULTIMATE-DAPT trial.

BACKGROUND: Current guidelines recommend administering dual antiplatelet therapy (DAPT) for 12 months to patients with acute coronary syndromes (ACS) and without contraindications after drug-eluting stent (DES) implantation. A recent study reported that 3 months of DAPT followed by ticagrelor monotherapy is effective and safe in ACS patients undergoing DES implantation compared with the standard duration of DAPT. However, it is unclear whether antiplatelet monotherapy with ticagrelor alone versus ticagrelor plus aspirin reduces the incidence of clinically relevant bleeding without increasing the risk of major adverse cardiovascular and cerebrovascular events (MACCEs) in ACS patients undergoing percutaneous coronary intervention (PCI) with DES implantation guided by either intravascular ultrasound (IVUS) or angiography who have completed a 1-month course of DAPT with aspirin plus ticagrelor. METHODS: The IVUS-ACS and ULTIMATE-DAPT is a prospective, multicenter, randomized, controlled trial designed to determine (1) whether IVUS-guided versus angiography-guided DES implantation in patients with ACS reduces the risk of target vessel failure (TVF) at 12 months and (2) whether ticagrelor alone versus ticagrelor plus aspirin reduces the risk of clinically relevant bleeding without increasing the risk of MACCE 1-12 months after the index PCI in ACS patients undergoing DES implantation guided by either IVUS or angiography. This study will enroll 3486 ACS patients eligible for DES implantation, as confirmed by angiographic studies. The patients who meet the inclusion criteria and none of the exclusion criteria will be randomly assigned in a 1:1 fashion to the IVUS- or angiography-guided group (first randomization). All enrolled patients will complete a 1-month course of DAPT with aspirin plus ticagrelor after the index PCI. Patients with no MACCEs or major bleeding (≥Bleeding Academic Research Consortium (BARC) 3b) within 30 days will be randomized in a 1:1 fashion to either the ticagrelor plus matching placebo (SAPT)group or ticagrelor plus aspirin (DAPT)group for an additional 11 months (second randomization). The primary endpoint of the IVUS-ACS trial is TVF at 12 months, including cardiac death, target vessel myocardial infarction (TVMI), or clinically driven target vessel revascularization (CD-TVR). The primary superiority endpoint of the ULTIMATE-DAPT trial is clinically relevant bleeding, defined as BARC Types 2, 3, or 5 bleeding, and the primary non-inferiority endpoint of the ULTIMATE-DAPT trial is MACCE, defined as cardiac death, myocardial infarction, ischemic stroke, CD-TVR, or definite stent thrombosis occurring 1-12 months in the second randomized population. CONCLUSION: The IVUS-ACS and ULTIMATE-DAPT trial is designed to test the efficacy and safety of 2 different antiplatelet strategies in ACS patients undergoing PCI with DES implantation guided by either IVUS or angiography. This study will provide novel insights into the optimal DAPT duration in ACS patients undergoing PCI and provide evidence on the clinical benefits of IVUS-guided PCI in ACS patients.

Postneoadjuvant surveillance and surgery as needed compared with postneoadjuvant surgery on principle in multimodal treatment for oesophageal cancer: a scoping review protocol.

INTRODUCTION: In current medical practice of curative treatment for non-metastatic oesophageal cancer, surgery on principle is carried out by oesophagectomy after neoadjuvant treatment. However, oesophagectomy is often associated with postoperative morbidity and mortality. Taking into account that modern neoadjuvant therapy is effective and many of patients show no vital tumour cells in the operative specimens, we aim to perform a scoping review as part of the development phase for a prospectively planned multicentre randomised controlled trial investigating 'surgery as needed vs surgery on principle in patients with postneoadjuvant complete response of oesophageal cancer' (Prospective trial registration number DRKS00022801). This scoping approach will allow us to finally define and/or adapt the research question including the design and methodology of the randomised controlled trial taking into account the findings for example, research gaps and/or pitfalls in the currently available study pool addressing this or very similar questions. METHODS AND ANALYSIS: To identify relevant research, we will conduct searches in the electronic databases Medline, Web of Science Core Collection, Cochrane Library and Science Direct. We will also check references of relevant studies and perform a cited reference research (forward citation tracking). Titles and abstracts of the records identified by the searches will be screened and full texts of all potentially relevant articles will be obtained. We will consider randomised trials and non-randomised controlled studies. Data extraction tables will be set up, including study and patients' characteristics, aim of study and reported outcomes. We will summarise the data using tables and figures (eg, bubble plots) to present the research landscape and to describe potential clusters and/or gaps to support the planning of a randomised trial in this patient population. ETHICS AND DISSEMINATION: Ethical approval is not required for this scoping review. Study findings will be shared by publication in a peer-reviewed journal and by presentation to key stakeholders on scientific meetings.

Genetic identification of inherited cystic kidney diseases for implementing precision medicine: a study protocol for a 3-year prospective multicenter cohort study.

BACKGROUND: Inherited cystic kidney disease is a spectrum of disorders in which clusters of renal cysts develop as the result of genetic mutation. The exact methods and pipelines for defining genetic mutations of inherited cystic kidney disease are not clear at this point. This 3-year, prospective, multicenter, cohort study was designed to set up a cohort of Korean patients with inherited cystic kidney disease, establish a customized genetic analysis pipeline for each disease subtype, and identify modifying genes associated with the severity of the disease phenotype. METHODS/DESIGN: From May 2020 to May 2022, we aim to recruit 800 patients and their family members to identify pathogenic mutations. Patients with more than 3 renal cysts in both kidneys are eligible to be enrolled. Cases of simple renal cysts and acquired cystic kidney disease that involve cyst formation as the result of renal failure will be excluded from this study. Demographic, laboratory, and imaging data as well as family pedigree will be collected at baseline. Renal function and changes in total kidney volume will be monitored during the follow-up period. Genetic identification of each case of inherited cystic kidney disease will be performed using a targeted gene panel of cystogenesis-related genes, whole exome sequencing (WES) and/or family segregation studies. Genotype-phenotype correlation analysis will be performed to elucidate the genetic effect on the severity of the disease phenotype. DISCUSSION: This is the first nationwide cohort study on patients with inherited cystic kidney disease in Korea. We will build a multicenter cohort to describe the clinical characteristics of Korean patients with inherited cystic kidney disease, elucidate the genotype of each disease, and demonstrate the genetic effects on the severity of the disease phenotype. TRIAL REGISTRATION: This cohort study was retrospectively registered at the Clinical Research Information Service ( KCT0005580 ) operated by the Korean Center for Disease Control and Prevention on November 5th, 2020.

Surgery for recurrent medulloblastoma: A review.

INTRODUCTION: Medulloblastoma (MB) is the most common malignant brain tumour in children. Despite significant progress in its management, a proportion of children relapse; tumour recurrence still carries a poor prognosis. While surgery is a mainstay of the management of primary MB, its role in recurrent MB is unclear. The objective of this literature review is to explore current practice and potential benefits of surgery in recurrent MB. MATERIAL AND METHODS: We reviewed all articles published in PubMed and Scholar from 1990 to 2018 with the following terms: "medulloblastoma" AND "recurrence" AND "neurosurgical procedures". Among 69 articles, 12 were directly relevant. RESULTS: A total of 581 cases of recurrent MB were identified from published series. Median time from diagnosis to relapse was 20.4months. The majority of relapses involved disseminated craniospinal disease and only one-fifth relapses was located in the posterior fossa. The outcome was consistently poor, with a median survival of 12.4% and a median survival time after relapse of 18.5months. In the HIP-SIOP-PNET4 study, surgery at relapse was performed in 25% of cases and was associated with improved prognosis in solitary posterior fossa recurrence. CONCLUSION: Recurrent medulloblastoma is often fatal in children who have previously received radiotherapy. The role of surgery in improving survival is unclear, but there is some evidence that resection of a focal single posterior fossa recurrence can bring survival benefit. The value of biopsy lies in the optimisation and selection of appropriate targeted therapy and in excluding a second malignancy.