Neuroimaging biomarkers for clinical trials of disease-modifying therapies in Alzheimer’s disease

Department of Neurology and the Athinoula A. Martinos Center for Biomedical Imaging, Massachusetts General Hospital, Charlestown, Massachusetts 02129, USA.
NeuroRx 05/2005; 2(2):348-60. DOI: 10.1602/neurorx.2.2.348
Source: PubMed

ABSTRACT The pathophysiologic process leading to neurodegeneration in Alzheimer's disease (AD) is thought to begin long before clinical symptoms develop. Existing therapeutics for AD improve symptoms, but increasing efforts are being directed toward the development of therapies to impede the pathologic progression of the disease. Although these medications must ultimately demonstrate efficacy in slowing clinical decline, there is a critical need for biomarkers that will indicate whether a candidate disease-modifying therapeutic agent is actually altering the underlying degenerative process. A number of in vivo neuroimaging techniques, which can reliably and noninvasively assess aspects of neuroanatomy, chemistry, physiology, and pathology, hold promise as biomarkers. These neuroimaging measures appear to relate closely to neuropathological and clinical data, such as rate of cognitive decline and risk of future decline. As this work has matured, it has become clear that neuroimaging measures may serve a variety of potential roles in clinical trials of candidate neurotherapeutic agents for AD, depending in part on the question of interest and phase of drug development. In this article, we review data related to the range of neuroimaging biomarkers of Alzheimer's disease and consider potential applications of these techniques to clinical trials, particularly with respect to the monitoring of disease progression in trials of disease-modifying therapies.

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Available from: Bradford Dickerson, Dec 13, 2013
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    • "In the following sections, specific strengths and weaknesses of the current technologies are reviewed. Because of their minimally invasive nature and sensitivity to the earliest changes within the brain substrate, many of the following neuroimaging methods have been promoted as being able to identify " leveraged cohorts " of individuals with an elevated risk of developing clinical AD in the short term [68]. This notion is yet to be realized, but many are hopeful that some of the novel techniques recently developed will provide breakthroughs in AD and other diseases. "
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