US approves Alzheimer’s drug designed to slow cognitive decline

9 Jan 2023

Image: © Gleb/

The approval has been welcomed as a ‘significant step’ for early Alzheimer’s treatment, but adverse effects have been noted from the drug’s clinical trials.

The US Food and Drug Administration (FDA) has approved an experimental drug that appears to slow the progression of Alzheimer’s disease.

The organisation said the drug – to be sold under the brand name Leqembi – is the second of a new category of approved medications that target the “fundamental pathophysiology” of Alzheimer’s disease.

The drug contains the antibody Lecanemab, which targets a harmful protein called amyloid beta. This protein builds up in the brains of those with Alzheimer’s disease.

A clinical trial on this antibody was shown to slow down cognitive and functional decline in Alzheimer’s patients by 27pc, though there were also various adverse effects noted.

The FDA granted the drug approval through an accelerated process, which allows the administration to fast-track drugs for serious conditions where there is an unmet medical need.

Billy Dunn, director of the FDA’s neuroscience office, said the disease “immeasurably incapacitates” those who have it and causes a “devastating effects on their loved ones”.

“This treatment option is the latest therapy to target and affect the underlying disease process of Alzheimer’s, instead of only treating the symptoms of the disease,” Dunn said.

Leqembi is being developed by Japan’s Eisai and its US partner Biogen. The FDA said it is anticipating the data from a phase 3 randomised, controlled clinical trial to confirm the drug’s clinical benefit.

The drug’s approval was welcomed by the Alzheimer Society of Ireland (ASI). The society said there are an estimated 64,000 people with dementia in Ireland and that number is anticipated to increase to 150,000 by 2045.

ASI research and policy manager Dr Laura O’Philbin said the decision is a “hugely positive and significant step” for the treatment of early Alzheimer’s disease. She said the ASI expects Eisai to file for marketing approval with the European Medicines Agency by March this year.

“The world is watching and waiting, and there is no denying that we have entered into a hugely exciting time in the treatment of Alzheimer’s Disease, with news of other drug therapies also expected this year,” O’Philbin said.

The FDA noted that the drug’s prescribing information contains a warning about potential adverse effects such as brain swelling and bleeding.

“It’s important to remember that we still have a way to go as Leqembi will need to go through the FDA’s full traditional process and that this drug will not be suitable for everyone,” O’Philbin said.

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Leigh Mc Gowran is a journalist with Silicon Republic