
Why there's excitement and skepticism about new Alzheimer's drug lecanemab
CBC
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Despite decades of research and billions of dollars, no treatment has ever definitively proven to slow the progression of Alzheimer's disease.
Two pharmaceutical companies have developed a drug that they say does just that.
On Tuesday, the full results of a worldwide human trial of the drug, called lecanemab, will be released at an Alzheimer's research conference in San Francisco.
The companies — Biogen of the U.S. and Eisai of Japan — have so far merely summarized the results of the human trial in a September news release. It said early-stage Alzheimer's disease patients who received lecanemab over the study's 18-month timeframe scored 27 per cent better on cognitive tests than those who'd received a placebo.
More than 600,000 Canadians are living with dementia, and Alzheimer's disease is the most common form. The Alzheimer's Society of Canada forecasts that number to reach one million by 2030.
While some experts say there is plenty of optimism to be found about lecanemab's potential, other have cautions and questions: What will the full data reveal? How much will the drug cost? How long can it stave off the devastating effects of Alzheimer's disease, which can include severe memory loss, mood changes and the inability to perform basic tasks.
Roughly translated, the results suggest lecanemab slowed the advance of Alzheimer's disease in its early stages by four-to-five months over the 18-month period of the study.
"We've had many failures and disappointments in drug development in this disease," said Dr. Sharon Cohen, medical director of the Toronto Memory Clinic, one of the human trial sites for lecanemab.
"This is a very hopeful time in Alzheimer's disease," Cohen said in an interview with CBC News. "We have, for the first time, an opportunity to slow down a bad disease at an early stage when people are still functioning well."
Cohen will be one of the researchers presenting the lecanemab data on Tuesday at the Clinical Trials on Alzheimer's Disease conference.
"Any slowing of disease — if what you're doing today you're still doing in six months or a year — that's a win, because we know this disease is relentless," Cohen said. "We have not been able to stop it from progressing previously."
The news release by Biogen and Eisai described the finding that the drug slowed cognitive decline by 27 per cent as "highly statistically significant."
But some are questioning how significant that would be for people living with early-stage Alzheimer's.