EMA, FDA endorse use of biomarkers in Alzheimer's drug trials

A news feature in Alzforum explains the impact of new guidelines for selecting volunteers in clinical trials of Alzheimer's drugs. The European Medicines Agency (EMA), the European counterpart to the U.S. Food and Drug Administration (FDA), has endorsed the use of biomarkers—substances in the body or measurements that serve as indicators of disease—to select patients to be included in drug trials. When Alzforum reporter Laura Bonetta asked experts from academia and industry what they thought about the EMA's decision, many saw it as a step in the right direction to better clinical trials.

Recent drug failures have highlighted that treatments may only be effective in people at the early stages of Alzheimer's disease; by the time the disease has progressed to full-blown dementia, most may provide little, if any, benefit. Traditionally, researchers have used memory and thinking tests to identify people with possible early-stage disease. However, a poor score on such tests is not always a harbinger of Alzheimer's; many people start having memory problems due to other conditions and will never develop Alzheimer's. So how can a researcher distinguish between the two? In recent years, researchers have found that by measuring the amounts of certain proteins found in the fluid surrounding the brain, and by assessing the volume of a part of the brain called the hippocampus, they could better predict whose memory problems would progress to the dreaded disease. These "biomarkers" are analogous to cholesterol measurements to determine who is at greater risk for developing heart disease.

Until now, agencies like the EMA and the FDA, which approve drug studies and decide which drugs can be sold to patients, had not given their regulatory green light to using biomarkers in Alzheimer's drug trials. The fact that the EMA has now done so for some biomarkers will encourage more researchers to incorporate these measurements into their studies. Experts who spoke with Alzforum were enthusiastic about such prospects, but they also pointed out caveats with relying on biomarker measurements.