One of the Most Promising Drugs for Alzheimer's Disease Fails in Clinical Trials

A report published in the Journal of the American Medical Association (JAMA) detailed the failure of the experimental drug idalopirdine to help people with mild to moderate Alzheimer's disease in three trials involving 2,525 persons in 34 countries, reports the Los Angeles Times . Idalopirdine failed to produce significant improvements in general measures of daily function among those taking it at any of three tested doses. The drug largely functioned to boost the supply of serotonin, which regulates mood, sleep, and appetite, and which diminishes in those with Alzheimer's disease. Idalopirdine also acts on glutamate, norepinephrine, acetylcholine, and dopamine, which also are affected by Alzheimer's. Following 24 weeks, subjects with Alzheimer's who received idalopirdine did no better than those who were given a placebo. Last autumn, another experimental drug, intepirdine, which also acted on many of the same brain systems as idalopirdine, was reported as a failure. Dr. David A. Bennett with Rush University's Alzheimer's Disease Center in Chicago wrote in an editorial published in JAMA that "better symptomatic therapies must continue to be pursued. However, from a public health perspective, delaying the onset of Alzheimer's disease dementia is the most effective approach to reduce the overall human and economic toll of the disease." Bennett noted this will involve earlier diagnosis of Alzheimer's among a broader spectrum of people, including those with no outward dementia symptoms. Those in the disease's earliest stages should be enrolled in clinical trials of preventive strategies faster, and in larger numbers.