Is the placebo control obsolete in a world after donepezil and vitamin E?

Recent clinical trials of donepezil and vitamin E have produced active therapeutic drugs for the treatment of patients with Alzheimer disease (AD). The AD research community is now in a gray zone between the absence of accepted therapies and the presence of completely effective therapies. How should these therapies guide the choice of the proper control for future AD clinical trials? The community equipoise principle can guide a process to answer this question. The principle is that a clinical trial should answer clinical questions that are valued by the community who will use the results of that trial. This means that the choice of the proper control for future AD clinical trials ought to be guided by the values of a community who will experience the results of those trials: physicians and patients or their representatives such as caregivers. The values of patients can be included by giving them a voice in the design and review of clinical trials. Community dialogue should be the norm for the design and review of AD clinical trials. We conclude with suggestions to foster this dialogue and issues that should be addressed.