Clinical trials : journal of the Society for Clinical Trials
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Currently, a growing placebo response rate has been observed in clinical trials for antidepressant drugs, a phenomenon that has made it increasingly difficult to demonstrate efficacy. The sequential parallel comparison design (SPCD) is a clinical trial design that was proposed to address this issue. The SPCD theoretically has the potential to reduce the sample-size requirement for a clinical trial and to simultaneously enrich the study population to be less responsive to the placebo. ⋯ It is possible to make an already complex design such as the SPCD adaptive, and thus more efficient, potentially overcoming the problem of placebo response at lower cost. Ultimately, such a design may expedite the approval of future effective treatments.
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Cluster randomized trials (CRTs) complicate the interpretation of standard research ethics guidelines for several reasons. For one, the units of allocation, intervention, and observation often may differ within a single trial. In the absence of tailored and internationally accepted ethics guidelines for CRTs, researchers and research ethics committees have no common standard by which to judge ethically appropriate practices in CRTs. Moreover, lack of familiarity with and consideration of the unique features of the CRT design by research ethics committees may cause difficulties in the research ethics review process, and amplify problems such as variability in the requirements and decisions reached by different research ethics committees. ⋯ CRT investigators are experiencing challenges in the research ethics review of their trials, including excessive delays, variability in process and outcome, and imposed requirements that can have negative consequences for study conduct. Investigators identified a clear need for ethics guidelines for CRTs and education of research ethics committees about distinct ethical issues in CRTs.
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Since 1994, the French National Agency for Research on AIDS and Viral Hepatitis (ANRS) has funded research sites in resource-limited countries (RLCs). These sites implement research on human immunodeficiency virus (HIV) infection and Hepatitis C. In parallel, international regulations and recommendations for clinical trials have evolved and proliferated. However, little guidance exists on how these should be interpreted and applied within academic trials and in the context of RLCs. After developing a specific Ethical Charter for research in developing countries in 2002, ANRS developed a set of quality indicators (QIs) as a monitoring tool for assessing compliance to international guidelines. ⋯ This innovative program allowed ANRS sites located in RLCs to share their GCP implementation experiences in order to build a list of relevant indicators for clinical trials. The next step is to collect data from ongoing HIV and hepatitis C trials in these settings and will assess the relevance of these indicators to document current quality of performance among trials in resource-limited settings.
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According to the International Conference on Harmonisation (ICH) and Food and Drug Administration (FDA) guidelines for paediatric clinical trials, bridging procedures can be used if disease progression, exposure-response relationships, and clinical endpoints are similar in adults and children. In these circumstances, confirmatory efficacy trials are not necessary; the evaluation of pharmacokinetics and safety ought to be sufficient for drug approval. ⋯ Paediatric trials are desirable and necessary to address important unmet medical needs. However, the types of studies supporting regulatory approval do not always reflect the recommendations available in paediatric guidelines, which allow for extrapolation and bridging approaches. This situation may be explained by the lack of awareness about the prerequisites for the use of bridging concepts and of a clear process for evaluating different strategies in paediatric development.
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Review
A systematic review of on-site monitoring methods for health-care randomised controlled trials.
Monitoring the conduct of clinical trials is recommended by International Conference of Harmonisation Good Clinical Practice (ICH GCP) guidelines and is integral to trial quality assurance. On-site monitoring, that is, visiting trial sites, is one part of this process but little is known about the procedures that are performed in practice. ⋯ This review demonstrated that on-site monitoring is utilised in trials worldwide but systems vary considerably with little evidence to support practice. These on-site monitoring practices need to be evaluated empirically, including costs, to provide robust evidence for the contribution of site visits to trial performance and quality.