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FDA Floats Draft Guidance for Alzheimer's Drug Development


The US Food and Drug Administration (FDA) today issued a proposal designed to assist companies focused on the development of new treatments for patients in the early stages of Alzheimer's disease (AD).
"The scientific community and the FDA believe that it is critical to identify and study patients with very early Alzheimer's disease before there is too much irreversible injury to the brain," Russell Katz, MD, director of the Division of Neurology Products in the FDA's Center for Drug Evaluation and Research, said in a statement announcing the draft proposal. "It is in this population that most researchers believe that new drugs have the best chance of providing meaningful benefit to patients," he added.
The guidance document outlines the FDA's current thinking about how best to identify and select patients with early AD, or those who are at risk of developing the disease, for enrollment in clinical trials, the FDA explains.
The proposal addresses the selection of endpoints for clinical trials in these populations, as well as the manner in which disease modification might be demonstrated.
"We recognize that the standard approaches to the selection of outcome measures historically used in the development of treatments for dementia of the Alzheimer's type have major limitations when applied to clinical trials enrolling patients in the early clinical stages of the disease, or before clinical impairment has emerged at all," the proposal states. "This guidance addresses some possible adaptations of the current approach to drug development for the treatment of the dementia stage of AD that appear more appropriate for clinical trials in the early stages of the illness."
A Tool for Discussion
"This draft guidance," Dr. Katz emphasized, "is intended to serve as a focus for continued discussions between the FDA and pharmaceutical sponsors, the academic community, advocacy groups, and the public. The FDA is committed to vigorously addressing Alzheimer's disease and will work with industry to help develop new treatments in this early population as expeditiously as possible."
The design of clinical trials specifically focused on the treatment of patients with established AD dementia (ie, dementia of the Alzheimer's type), or any of the autosomal dominant forms of Alzheimer's, is not explicitly discussed in the guidance, "although many of the principles in this guidance will be pertinent to this setting as well," the FDA notes.
The agency is seeking public comment on the draft guidance for 60 days. Instructions on how to submit comments are included in a related Federal Register notice issued today.
The FDA proposal is part of the US Department of Health and Human Services' (HHS's) efforts under the National Plan to Address Alzheimer's Disease, which calls for both the government and the private sector to intensify efforts to treat or prevent Alzheimer's and related dementias and to improve care and services.
The proposal responds to recommendations from a May 2012 HHS and National Institutes of Health Alzheimer's research summit to conduct clinical trials in at-risk individuals without symptoms and to develop and validate new measures so that Alzheimer's can be measured at the earliest possible time in the course of the disease.

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