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Improving Drug Trials for Mild to Moderate Alzheimer's Disease

Published online by Cambridge University Press:  02 December 2014

David B. Hogan
David B. Hogan*
Affiliation:
The Health Sciences Centre, University of Calgary, Calgary, Alberta, Canada
*
Health Sciences Centre, University of Calgary, 3330 Hospital Dr. N.W., Calgary, Alberta, T2N 4N1, Canada.
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Abstract

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Over the last two decades, numerous studies have been conducted on subjects with mild to moderate Alzheimer's disease. The objective of this paper was to review concerns raised in the literature about the design and methodology of these clinical trials and to make recommendations to deal with the limitations identified. Concerns raised in the literature include the following: undue focus on statistical rather than clinical significance; the need for further pharmacoeconomic evaluations; the nonrepresentativeness of the study populations; perceived inadequacies in the direct-comparison studies conducted to date; the limitations of open-label extension studies; the inability of standard psychometric tools to document all the relevant treatment effects; the ethics of placebo-controlled trials; and, problems caused by the actions of the regulatory authorities. Recommendations are made to deal with the issues raised.

Résumé:

RÉSUMÉ:

Au cours des vingt dernières années plusieurs études ont été faites chez des sujets atteints de la maladie d'Alzheimer de légère à modérée. L'objectif de cet article était de revoir la littérature concernant les problèmes relatifs au plan d'étude et à la méthodologie de ces essais cliniques et de faire des recommandations pour pallier ces problèmes. Les problèmes suivants ont été relevés dans la littérature : l'accent est mis sur la signification statistique plutôt que sur la signification clinique; la nécessité d'évaluations pharmaco-économiques plus poussées; la non-représentativité des populations étudiées; les imperfections relevées dans les études de comparaison directe effectuées jusqu'à maintenant; les limites des prolongations d'essais ouverts; l'incapacité des outils psychométriques standards à documenter les effets thérapeutiques pertinents; l'éthique des essais contrôlés par placebo et les problèmes engendrés par les dispositions adoptées par les autorités chargées de la réglementation. Nous faisons des recommandations pour résoudre les problèmes décelés.

Type
Original Articles
Information
Canadian Journal of Neurological Sciences , Volume 34 , Issue S1 , March 2007 , pp. S97 - S102
Copyright
Copyright © The Canadian Journal of Neurological 2007

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