Health Canada authorizes long-awaited drug to slow early-stage Alzheimer’s disease

Health Canada has authorized lecanemab, a drug shown in this handout image, that can slow the progression of Alzheimer's disease. THE CANADIAN PRESS/Handout - Eisai Co., Ltd. (Mandatory Credit)

TORONTO — Health Canada has authorized a drug shown to slow the progression of Alzheimer’s disease.

Lecanemab is the first medication approved in Canada that targets the buildup of amyloid plaque in the brain, which is believed to be an underlying cause of Alzheimer’s disease.

The drug is a lab-made antibody that binds to the amyloid proteins and helps neutralize and clear them from the brain.

Lecanemab must be administered in the early stages of dementia when there is mild cognitive impairment.

Adam Morrison, a spokesperson for the Alzheimer Society of Ontario, says patients and their families have been anxiously awaiting the approval of lecanemab — also known by its brand name Leqembi — in Canada.

Morrison said Alzheimer societies are urging Canada’s Drug Agency and provincial governments to quickly bring the drug to market and publicly fund it so all eligible patients can afford to take it, noting it costs about US$26,000 a year in other countries.

Lecanemab is a treatment, not a cure, that needs to be administered intravenously every two weeks, Morrison said.

“What we hear from our clients is that ‘this sounds like a drug that can give me more time. This can give me more time with my family,’ and that’s a really, really significant piece that we’ve been hearing about a lot,” he said.

Lecanemab is approved in about 50 countries, a news release from manufacturer Eisai Co., Ltd., said on Monday.

It was approved by the U.S. Food and Drug Administration in 2023.

Lecanemab was tested in a global Phase 3 clinical trial, Eisai said in the release, noting that it would continue to “submit clinical assessment data captured from participants in real-world clinical practice.”

Possible side-effects of lecanemab include brain swelling or bleeding, although in most cases they are visible on MRI scans but don’t cause any symptoms, said Dr. Andrew Frank, a cognitive neurologist and medical director of the Bruyère Memory Program in Ottawa.

“This is likely because the antibodies are reacting with the amyloid and as the amyloid protein is being cleared, there may be inflammation to do that which can lead to swelling in the brain and/or bleeding in the brain,” said Frank in an interview with The Canadian Press last year while awaiting approval of lecanemab.

Frank, who has consulted for Eisai Canada, said symptoms can include headache, dizziness or lightheadedness, but in rare cases can also include serious conditions such as seizures or stroke-like symptoms.

Fewer than one per cent of clinical trial participants had “persistent or possibly permanent side-effects or symptoms” once the medication was stopped, he said.

“I support these medications being accessible to Canadians, so that they can make a decision on the risk-benefit balance themselves, with their families and with their physicians to make a choice on whether or not the benefit of slowing the disease outweighs the risk of those serious side-effects,” Frank said.

This report by The Canadian Press was first published Oct. 27, 2025.

Canadian Press health coverage receives support through a partnership with the Canadian Medical Association. CP is solely responsible for this content.

Nicole Ireland, The Canadian Press