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NIA statement on report of lecanemab reducing cognitive decline in Alzheimer’s clinical trial

This page was updated to include the U.S. Food and Drug Administration’s July 6, 2023, announcement about approval of lecanemab for the treatment of Alzheimer’s disease. 

The U.S. Food and Drug Administration (FDA) today granted traditional approval for Leqembi (lecanemab-irmb) for the treatment of Alzheimer’s. This occasion — combined with ongoing scientific pursuits and advances in Alzheimer’s and related dementias research — helps mark decades of scientific progress toward effectively treating and preventing these diseases. NIA remains eternally grateful to the research community as well as to the many clinical trial participants who have played significant roles in advancing knowledge, data, and discoveries. 

Jan. 06, 2023

This page was updated to include the U.S. Food and Drug Administration’s Jan. 6, 2023, announcement about accelerated approval of lecanemab for the treatment of Alzheimer’s disease.

Today, the U.S. Food and Drug Administration (FDA) announced accelerated approval for Leqembi (lecanemab-irmb) for the treatment of Alzheimer’s disease. Lecanemab is made by the pharmaceutical companies Eisai and Biogen. In 2022, researchers at Biogen/Eisai published the results of a phase 3 clinical trial called Clarity-AD in The New England Journal of Medicine. The results showed lecanemab produced a clear yet modest clinical benefit in people who were in the early stages of Alzheimer’s. In comparison with a placebo, the drug slowed the rate of cognitive decline over 18 months and reduced the levels of brain amyloid.

Oct. 03, 2022

Pharmaceutical companies Eisai and Biogen recently announced data for a phase 3 Alzheimer’s disease clinical trial. The results show that lecanemab, an anti-amyloid antibody, slowed the rate of cognitive decline by 27% in an 18-month study involving participants experiencing the early stage of Alzheimer’s. The incidence of adverse events was 21.3% for those who received lecanemab and 9.3% for those who received a placebo. About 25% of the U.S. participants in this study were Hispanic and African American.

The NIH National Institute on Aging (NIA) eagerly awaits publication of the data in a peer-reviewed scientific journal. Potentially promising outcomes such as this one are the result of sustained public investment in medical research, the tireless work of scientists around world, and the help of people living with Alzheimer’s and their caregivers. Although NIA did not fund the lecanemab study, our decades of research paved the way for this Alzheimer’s trial that notably met its primary and secondary endpoints.

Specifically, NIA funding was integral to helping us understand the role of amyloid, the protein targeted by lecanemab. We supported a wide variety of investigations that led to the discovery of many candidate antibodies that were the basis for immunotherapies such as lecanemab and helped translate those findings into potential treatments. Additionally, the selection of participants for lecanemab clinical trials hinged on amyloid PET imaging, a technology that was developed with publicly funded research conducted and funded by NIA.

NIA is currently funding three trials to evaluate lecanemab’s effectiveness at treating different types of Alzheimer’s disease and related dementias. Through its AHEAD 3-45 Study, researchers will test the safety and efficacy of lecanemab on participants who have varying amounts of amyloid pathology, but do not yet have levels of cognitive decline to warrant a dementia diagnosis. One group, called A3, will involve participants who have intermediate levels of beta amyloid as seen on brain scans. Another group, called A45, will involve participants who have elevated levels of beta amyloid.

Through the NIA Dominantly Inherited Alzheimer Network Trials Unit (DIAN-TU), researchers will use lecanemab in combination with another drug, E2814 in participants who are genetically susceptible to early-onset Alzheimer’s, a rare form of the disease that typically occurs in a person’s 30s to mid-60s. E2814 is designed to counteract harmful versions of tau, another hallmark protein associated with Alzheimer’s. The researchers will evaluate the effects of E2814 alone, lecanemab alone, and the combination of the two drugs. 

These efforts and many others can only happen in collaboration with the research community, industry, and importantly, public participation. NIA is grateful for the many individuals who have participated in clinical trials that helped advance knowledge, and we continue to emphasize the enormous importance of participating in research studies. We remain committed to recruiting and retaining a broad range of clinical trial participants from diverse communities, and to expanding and diversifying the Alzheimer’s and related dementias research workforce.

NIA-funded scientists will also continue to identify and test new dementia drug candidates, advance comprehensive models of care, develop new biomarker tests, explore disease risk and possible protective factors throughout the life course, examine disparities in dementia prevalence and care, and improve the understanding of the role of genetics and other disease mechanisms.

Richard J. Hodes, M.D.
Director, National Institute on Aging
National Institutes of Health

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