Will unpredictable side effects dim the promise of new Alzheimer ’s drugs?

A sea change is underway in the treatment of Alzheimer’s disease, where for the first time a drug that targets the disease’s pathology and clearly slows cognitive decline has hit the U.S. market. A related therapy will likely be approved in the coming months. As many neurologists, patients, and brain scientists celebrate, they’re also nervously eyeing complications from treatment: brain swelling and bleeding, which in clinical trials affected up to about one-third of patients and ranged from asymptomatic to fatal. The side effect—amyloid-related imaging abnormalities, or ARIA—remains mysterious. “We don’t really understand what it is, what causes it, and what we can do about it,” says neurologist R. Scott Turner, director of the Memory Disorders Program at Georgetown University. The drugs triggering the problem are monoclonal antibodies that mop up beta amyloid, a protein that accumulates in the brains of people with Alzheimer’s. One such antibody, lecanemab, marketed as Leqembi by Eisai and Biogen, won full approval in the United States last month after trials showed it modestly slowed cognitive decline in early disease. Another, Eli Lilly & Co.’s donanemab, had similar results and is under regulatory review. These therapies aim to clear clumps of amyloid, called plaques, from between neurons. But such plaques can also build up in brain blood vessels, and breaking them down there may set off ARIA. The condition co...
Source: Science of Aging Knowledge Environment - Category: Geriatrics Source Type: research