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10,009 result(s) for "multicenter study (topic)"
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A reinvestigation of recruitment to randomised, controlled, multicenter trials: a review of trials funded by two UK funding agencies
Background Randomised controlled trials (RCTs) are the gold standard assessment for health technologies. A key aspect of the design of any clinical trial is the target sample size. However, many publicly-funded trials fail to reach their target sample size. This study seeks to assess the current state of recruitment success and grant extensions in trials funded by the Health Technology Assessment (HTA) program and the UK Medical Research Council (MRC). Methods Data were gathered from two sources: the National Institute for Health Research (NIHR) HTA Journal Archive and the MRC subset of the International Standard Randomised Controlled Trial Number (ISRCTN) register. A total of 440 trials recruiting between 2002 and 2008 were assessed for eligibility, of which 73 met the inclusion criteria. Where data were unavailable from the reports, members of the trial team were contacted to ensure completeness. Results Over half (55%) of trials recruited their originally specified target sample size, with over three-quarters (78%) recruiting 80% of their target. There was no evidence of this improving over the time of the assessment. Nearly half (45%) of trials received an extension of some kind. Those that did were no more likely to successfully recruit. Trials with 80% power were less likely to successfully recruit compared to studies with 90% power. Conclusions While recruitment appears to have improved since 1994 to 2002, publicly-funded trials in the UK still struggle to recruit to their target sample size, and both time and financial extensions are often requested. Strategies to cope with such problems should be more widely applied. It is recommended that where possible studies are planned with 90% power.
Recruitment and retention of participants in randomised controlled trials: a review of trials funded and published by the United Kingdom Health Technology Assessment Programme
BackgroundSubstantial amounts of public funds are invested in health research worldwide. Publicly funded randomised controlled trials (RCTs) often recruit participants at a slower than anticipated rate. Many trials fail to reach their planned sample size within the envisaged trial timescale and trial funding envelope.ObjectivesTo review the consent, recruitment and retention rates for single and multicentre randomised control trials funded and published by the UK's National Institute for Health Research (NIHR) Health Technology Assessment (HTA) Programme.Data sources and study selectionHTA reports of individually randomised single or multicentre RCTs published from the start of 2004 to the end of April 2016 were reviewed.Data extractionInformation was extracted, relating to the trial characteristics, sample size, recruitment and retention by two independent reviewers.Main outcome measuresTarget sample size and whether it was achieved; recruitment rates (number of participants recruited per centre per month) and retention rates (randomised participants retained and assessed with valid primary outcome data).ResultsThis review identified 151 individually RCTs from 787 NIHR HTA reports. The final recruitment target sample size was achieved in 56% (85/151) of the RCTs and more than 80% of the final target sample size was achieved for 79% of the RCTs (119/151). The median recruitment rate (participants per centre per month) was found to be 0.92 (IQR 0.43–2.79) and the median retention rate (proportion of participants with valid primary outcome data at follow-up) was estimated at 89% (IQR 79–97%).ConclusionsThere is considerable variation in the consent, recruitment and retention rates in publicly funded RCTs. Investigators should bear this in mind at the planning stage of their study and not be overly optimistic about their recruitment projections.
Strategies for the use of Ginkgo biloba extract, EGb 761®, in the treatment and management of mild cognitive impairment in Asia: Expert consensus
Background Mild cognitive impairment (MCI) is a neurocognitive state between normal cognitive aging and dementia, with evidence of neuropsychological changes but insufficient functional decline to warrant a diagnosis of dementia. Individuals with MCI are at increased risk for progression to dementia; and an appreciable proportion display neuropsychiatric symptoms (NPS), also a known risk factor for dementia. Cerebrovascular disease (CVD) is thought to be an underdiagnosed contributor to MCI/dementia. The Ginkgo biloba extract, EGb 761®, is increasingly being used for the symptomatic treatment of cognitive disorders with/without CVD, due to its known neuroprotective effects and cerebrovascular benefits. Aims To present consensus opinion from the ASian Clinical Expert group on Neurocognitive Disorders (ASCEND) regarding the role of EGb 761® in MCI. Materials & Methods The ASCEND Group reconvened in September 2019 to present and critically assess the current evidence on the general management of MCI, including the efficacy and safety of EGb 761® as a treatment option. Results EGb 761® has demonstrated symptomatic improvement in at least four randomized trials, in terms of cognitive performance, memory, recall and recognition, attention and concentration, anxiety, and NPS. There is also evidence that EGb 761® may help delay progression from MCI to dementia in some individuals. Discussion EGb 761® is currently recommended in multiple guidelines for the symptomatic treatment of MCI. Due to its beneficial effects on cerebrovascular blood flow, it is reasonable to expect that EGb 761® may benefit MCI patients with underlying CVD. Conclusion As an expert group, we suggest it is clinically appropriate to incorporate EGb 761® as part of the multidomain intervention for MCI. EGb 761® has demonstrated improvement in mild cognitive impairment (MCI) symptoms in at least four randomized trails, and is currently recommended for MCI in multiple clinical guidelines. The ASian clinical expert group on Neurocognitive Disorders (ASCEND) suggests that it is clinically appropriate to incorporate EGb 761® as part of the multidomain intervention for MCI, including cases with underlying CVD.
Managing clustering effects and learning effects in the design and analysis of multicentre randomised trials: a survey to establish current practice
Background Patient outcomes can depend on the treating centre, or health professional, delivering the intervention. A health professional’s skill in delivery improves with experience, meaning that outcomes may be associated with learning. Considering differences in intervention delivery at trial design will ensure that any appropriate adjustments can be made during analysis. This work aimed to establish practice for the allowance of clustering and learning effects in the design and analysis of randomised multicentre trials. Methods A survey that drew upon quotes from existing guidelines, references to relevant publications and example trial scenarios was delivered. Registered UK Clinical Research Collaboration Registered Clinical Trials Units were invited to participate. Results Forty-four Units participated ( N  = 50). Clustering was managed through design by stratification, more commonly by centre than by treatment provider. Managing learning by design through defining a minimum expertise level for treatment provider was common (89%). One-third reported experience in expertise-based designs. The majority of Units had adjusted for clustering during analysis, although approaches varied. Analysis of learning was rarely performed for the main analysis ( n  = 1), although it was explored by other means. The insight behind the approaches used within and reasons for, or against, alternative approaches were provided. Conclusions Widespread awareness of challenges in designing and analysing multicentre trials is identified. Approaches used, and opinions on these, vary both across and within Units, indicating that approaches are dependent on the type of trial. Agreeing principles to guide trial design and analysis across a range of realistic clinical scenarios should be considered.
Streamlining the institutional review board process in pragmatic randomized clinical trials: challenges and lessons learned from the Aspirin Dosing: A Patient-centric Trial Assessing Benefits and Long-Term Effectiveness (ADAPTABLE) trial
Background New considerations during the ethical review processes may emerge from innovative, yet unfamiliar operational methods enabled in pragmatic randomized controlled trials (RCT), potentially making institutional review board (IRB) evaluation more complex. In this manuscript, key components of the pragmatic “Aspirin Dosing: A Patient-Centric Trial Assessing Benefits and Long-term Effectiveness (ADAPTABLE)” randomized trial that required a reappraisal of the IRB submission, review, and approval processes are discussed. Main text ADAPTABLE is a pragmatic, multicenter, open-label RCT evaluating the comparative effectiveness of two doses of aspirin widely used for secondary prevention (81 mg and 325 mg) in 15,000 patients with an established history of atherosclerotic cardiovascular disease. The electronic informed consent form is completed online by the participants at the time of enrollment, and endpoint ascertainment is conducted through queries of electronic health records. IRB challenges encountered regarding centralized IRB evaluation, electronic informed consent, patient engagement, and risk determination in ADAPTABLE are described in this manuscript. The experience of ADAPTABLE encapsulates how pragmatic protocol components intended to facilitate the study conduct have been tempered by unexpected, yet justified concerns raised by local IRBs. How the lessons learned can be applied to future similar pragmatic trials is delineated. Conclusion Development of engaging communication channels between IRB and study personnel in pragmatic randomized trials as early as at the time of protocol design allows to reduce issues with IRB approval. Integrations of the lessons learned in ADAPTABLE regarding the IRB process for centralized IRBs, informed consent, patient engagement, and risk determination can be emulated and will be instrumental in future pragmatic studies.
Neoadjuvant chemoradiotherapy plus surgery versus active surveillance for oesophageal cancer: a stepped-wedge cluster randomised trial
Background Neoadjuvant chemoradiotherapy (nCRT) plus surgery is a standard treatment for locally advanced oesophageal cancer. With this treatment, 29% of patients have a pathologically complete response in the resection specimen. This provides the rationale for investigating an active surveillance approach. The aim of this study is to assess the (cost-)effectiveness of active surveillance vs. standard oesophagectomy after nCRT for oesophageal cancer. Methods This is a phase-III multi-centre, stepped-wedge cluster randomised controlled trial. A total of 300 patients with clinically complete response (cCR, i.e. no local or disseminated disease proven by histology) after nCRT will be randomised to show non-inferiority of active surveillance to standard oesophagectomy (non-inferiority margin 15%, intra-correlation coefficient 0.02, power 80%, 2-sided α 0.05, 12% drop-out). Patients will undergo a first clinical response evaluation (CRE-I) 4–6 weeks after nCRT, consisting of endoscopy with bite-on-bite biopsies of the primary tumour site and other suspected lesions. Clinically complete responders will undergo a second CRE (CRE-II), 6–8 weeks after CRE-I. CRE-II will include 18F–FDG-PET-CT, followed by endoscopy with bite-on-bite biopsies and ultra-endosonography plus fine needle aspiration of suspected lymph nodes and/or PET- positive lesions. Patients with cCR at CRE-II will be assigned to oesophagectomy (first phase) or active surveillance (second phase of the study). The duration of the first phase is determined randomly over the 12 centres, i.e., stepped-wedge cluster design. Patients in the active surveillance arm will undergo diagnostic evaluations similar to CRE-II at 6/9/12/16/20/24/30/36/48 and 60 months after nCRT. In this arm, oesophagectomy will be offered only to patients in whom locoregional regrowth is highly suspected or proven, without distant dissemination. The main study parameter is overall survival; secondary endpoints include percentage of patients who do not undergo surgery, quality of life, clinical irresectability (cT4b) rate, radical resection rate, postoperative complications, progression-free survival, distant dissemination rate, and cost-effectiveness. We hypothesise that active surveillance leads to non-inferior survival, improved quality of life and a reduction in costs, compared to standard oesophagectomy. Discussion If active surveillance and surgery as needed after nCRT leads to non-inferior survival compared to standard oesophagectomy, this organ-sparing approach can be implemented as a standard of care.
A statistical approach to central monitoring of data quality in clinical trials
Background Classical monitoring approaches rely on extensive on-site visits and source data verification. These activities are associated with high cost and a limited contribution to data quality. Central statistical monitoring is of particular interest to address these shortcomings. Purpose This article outlines the principles of central statistical monitoring and the challenges of implementing it in actual trials. Methods A statistical approach to central monitoring is based on a large number of statistical tests performed on all variables collected in the database, in order to identify centers that differ from the others. The tests generate a high-dimensional matrix of p-values, which can be analyzed by statistical methods and bioinformatic tools to identify extreme centers. Results Results from actual trials are provided to illustrate typical findings that can be expected from a central statistical monitoring approach, which detects abnormal patterns that were not (or could not have been) detected by on-site monitoring. Limitations Central statistical monitoring can only address problems present in the data. Important aspects of trial conduct such as a lack of informed consent documentation, for instance, require other approaches. The results provided here are empirical examples from a limited number of studies. Conclusion Central statistical monitoring can both optimize on-site monitoring and improve data quality and as such provides a cost-effective way of meeting regulatory requirements for clinical trials.
Regulatory and operational challenges in conducting Asian International Academic Trial for expanding the indications of cancer drugs
There are many differences between Asian regions in terms of the regulatory requirements and operational procedures in conducting international academic clinical trials for the approval of new drugs. The National Cancer Center Hospital in Japan has launched an international investigator‐initiated registration‐directed trial (IIRDT) in Japan, Korea, Taiwan, and Singapore, aiming at obtaining pharmaceutical approval in participating regions. Differences in regulatory and operational procedures were identified while coordinating the trial. In Japan, regulatory authority reviews should be performed after approval by institutional review boards for IIRDT, whereas in other regions these can be done in parallel. There were disparities in Good Manufacturing Practice‐related documents between regions. Several differences were found regarding investigational product (IP) management, specifically concerning labeling, import/export procedures, and customs clearance costs. On the other hand, safety reporting procedures were relatively well‐harmonized in accordance with International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use, Clinical Safety Data Management: Definitions and Standards for Expedited Reporting (ICH‐E2A). Regions also differed in per‐patient costs, due to varying regulations for academic registration‐directed trials. In conclusion, the observed differences among Asian regions should be harmonized to facilitate international academic trials in Asia and thus resolve unmet patient needs worldwide. Study Highlights WHAT IS THE CURRENT KNOWLEDGE ON THE TOPIC? International clinical trials have become common because they make it possible to accrue patients faster and obtain new drug approval in wider areas. However, pharmaceutical regulatory differences hinder the efficient conduct of international clinical trials, especially in academia. WHAT QUESTION DID THIS STUDY ADDRESS? We conducted an academic international clinical trial on new drug applications in four Asian countries and clarified pharmaceutical regulatory differences and operational difficulties. WHAT DOES THIS STUDY ADD TO OUR KNOWLEDGE? The study identified differences between countries in terms of regulatory affairs, institutional review board (IRB) review processes, investigational new drug (IND) dossiers, investigational product (IP) management procedures, and clinical trial costs, while safety reporting procedures were relatively harmonized. Japan utilizes investigator‐initiated registration‐directed trials, an advanced regulatory system for new drug application by academia, but the other countries do not. HOW MIGHT THIS CHANGE CLINICAL PHARMACOLOGY OR TRANSLATIONAL SCIENCE? Harmonization of pharmaceutical regulations and trial initiation procedures, and regulatory reform of clinical trial costs are important to accelerate academic international clinical trials for new drug applications.
Design, conduct, analysis and reporting of a multi-national placebo-controlled trial of activated protein C for persistent septic shock
The role of drotrecogin alfa (activated) (DAA) in severe sepsis remains controversial and clinicians are unsure whether or not to treat their patients with DAA. In response to a request from the European Medicines Agency, Eli Lilly will sponsor a new placebo-controlled trial and history suggests the results will be subject to great scrutiny. An academic steering committee will oversee the conduct of the study and will write the study manuscripts. The steering committee intends that the study will be conducted with the maximum possible transparency; this includes publication of the study protocol and a memorandum of understanding which delineates the role of the sponsor. The trial has the potential to provide clinicians with valuable data but patients will only benefit if clinicians have confidence in the conduct, analysis and reporting of the trial. This special article describes the process by which the trial was developed, major decisions regarding trial design, and plans for independent analysis, interpretation and reporting of the data.
Learning from OCTET – exploring the acceptability of clinical trials management methods
Background Conducting research can be time consuming, difficult and challenging. Guidance and pragmatic advice focussing on randomised controlled trial conduct are available but do not necessarily constitute comprehensive guidance. A successful trial is one that recruits to time and target and collects high-quality data within the originally agreed budget. Standardised trial management tools have outlined key project management elements for a successful trial as a method of ensuring good practice in research trials: initiation, planning, execution, monitoring and closure. Lessons are also frequently learnt during the development and conduct of trials but rarely shared for the benefit of others. For the wider research team, the key focus will always be on the execution and delivery of a study. The aim of this study was to evaluate the acceptability of clinical trials management methods, focussing on study execution and monitoring, as implemented in the National Institute for Health Research Health Technology Assessment Programme-funded Obsessive Compulsive Treatment Efficacy Trial (OCTET). Methods Workshops, questionnaires and semi-structured interviews were used to explore acceptability of trial management methods with members of the OCTET Trial research team. Nine members participated in the focus group, 10 completed a questionnaire and 20 were interviewed as part of qualitative work for the main OCTET study. Data was collected and analysed using thematic analysis. Results Six key themes were identified: support; communication; processes; resources; training and ethos. Clear and open communication, enthusiasm and accessibility of the trial managers and chief investigator were consistently noted as an important facet of the successful running of the trial. Clear resources and training materials were also found to be crucial in helping staff to work within the trial setting. Constructive suggestions were also made for improvement of these resources; for example, including both checklists and flowcharts within trial processes. Conclusion Organisation, openness and positivity are crucial for executing a trial successfully, whilst clear and focussed processes and resources are essential in monitoring and controlling the trial progress. Although derived from a single study, these findings are likely to be applicable to the successful conduct of all trials. Trial managers should consider developing these elements when setting up a study. Trial registration Clinical Trial Registry, ID: ISRCTN73535163 . Registered prospectively on 5 April 2011.