https://issuesinsights.com/2023/07/20/fdas-approval-of-a-new-alzheimers-drug-is-a-real-but-very-modest-advance/
The Food and Drug Administration on July 6 granted full approval to the first therapy for Alzheimer’s that slows the cognitive decline associated with the disease. That “first” is good news, because it validates a therapeutic approach that has long been in doubt, but more important, it benefits patients afflicted with a terrible disease.
The approval is hardly a breakthrough, however: The benefits of the drug, Leqembi (lecanemab) are meager; it does not restore lost function; it is expensive and administered intravenously every two weeks; and there are occasionally severe side effects. Nevertheless, my neurologist friends tell me that they’re being inundated with inquiries about Leqembi from Alzheimer’s patients and their families.
Alzheimer’s disease is an irreversible, progressive brain disorder that afflicts more than 6.5 million Americans. It slowly destroys memory and cognitive skills and eventually, the ability to perform even simple tasks. Although the specific causes of Alzheimer’s are not fully understood, it is characterized by changes in the brain, including the formation of various abnormal structures that result in loss of neurons and their connections.
The FDA had previously granted Leqembi accelerated approval based on a “surrogate endpoint” short of demonstrated clinical benefit, based on its ability to reduce amyloid plaques, or clumps, in the brain, a hallmark of Alzheimer’s. As a postmarketing condition of the accelerated approval, the drug manufacturer, Eisai, was required to conduct a clinical trial to confirm the anticipated clinical benefit of Leqembi. Safety and efficacy were evaluated in a Phase 3 multicenter, randomized, placebo-controlled clinical trial that included 1,795 patients.
That confirmatory trial, which was reported earlier this year in the New England Journal of Medicine, showed that in patients in the early stages of the disease, the drug slowed cognitive and functional decline modestly – perhaps by about five months – over 18 months compared with placebo.