NIH-Supported Studies Will Focus on New Alzheimer’s Treatments
Four clinical trials to be conducted over 5 years (Jan. 14)
With research funding from the National Institutes of Health (NIH), the Alzheimer’s Disease Cooperative Study (ADCS) network will undertake four major trials aimed at finding new treatments for the disease. In this round of clinical trials, the ADCS will test drug and exercise interventions in people in the early stages of Alzheimer's disease (AD); will examine a medication to reduce agitation in people with Alzheimer’s dementia; and will evaluate a novel approach to speed the testing of drugs in clinical studies.
The ADCS is a consortium made up of more than 70 research centers in the U.S. and Canada, with a focus on advancing studies of interventions that might not otherwise be tested by industry.
The ADCS and this latest round of trials are critical to accomplishing the research goals set forth in the “National Plan to Address Alzheimer’s Disease,” announced by the Department of Health and Human Services in May 2012. The plan’s primary objective is to prevent and effectively treat AD by 2025.
The four studies made possible by the new NIH funding are:
- The A4 Trial: The development of plaques made up of amyloid protein fragments is a key feature of AD. Because AD-related brain changes take place years, even decades, before symptoms appear, scientists are now aiming to test therapies earlier in the disease process. The A4 (Anti-Amyloid Treatment in Asymptomatic Alzheimer’s Disease) secondary prevention trial will test an amyloid-clearing drug in the presymptomatic stage of AD in 1,000 older individuals who have had positron emission tomography (PET) brain images that show abnormal levels of amyloid accumulation. Cognitive tests over 3 years will determine whether the drug is effective in maintaining cognitive health, and imaging tests will track structural and functional brain changes.
- The Exercise MCI Trial: Although exercise is widely recommended to maintain physical function and to reduce the risk of several age-related medical conditions, such as cardiovascular disease and diabetes, it has not been shown in long-term clinical trials to improve cognition or to alter the hallmarks of AD in the brain. The objective of the randomized, controlled Exercise MCI Trial is to find out whether supervised aerobic exercise can influence cognitive decline, slow brain atrophy, or mitigate the pathology of AD in older adults with mild cognitive impairment (MCI) — a condition that often leads to AD.
- The Prazosin for Treating Agitation Trial: Disruptive agitation is often a chronic problem in people with AD, dramatically increasing caregiver burden and patient distress, and often leading to long-term care outside the home. Current drugs for the treatment of agitation are generally ineffective and may even cause additional harm in older people, such as increasing the risk of stroke or excessive sedation. The Prazosin for Treating Agitation Trial will test the use of the generic drug prazosin as a treatment for agitation that may also be well-tolerated in frail and elderly patients.
- The CSF Pharmacodynamic Trial: When testing potential drug therapies that target AD pathways, scientists use cerebrospinal fluid (CSF) and plasma biomarkers to learn whether the compound crossed the blood–brain barrier and engaged the relevant target. In addition, these biomarkers help track the relationship between blood levels and central nervous system effects. To increase the efficacy and speed of drug development, the CSF Pharmacodynamic Trial will employ advanced methods that sample CSF and plasma levels over time. These methods will track levels of several AD-related proteins to help researchers better understand how a drug influences the pathology of AD and to help guide decisions on whether a drug warrants further clinical testing.
Source: NIH; January 14, 2013.