Critics, however, highlight concerns about its clinical benefits and serious side effects, such as amyloid-related imaging abnormalities (ARIA), which include brain swelling and bleeding. These side effects, although rare, have been linked to a few deaths in extended trials.
The drug's Phase III trials showed a 27% reduction in cognitive decline compared to a placebo, but critics argue this translates to only a modest absolute difference on cognitive scales.
Ongoing trials and studies, including recent findings presented at the Alzheimer’s Association International Conference, suggest that lecanemab might offer benefits if maintained over time, but more data is needed. Concerns about the drug’s cost — exceeding $20,000 per year in the US — and the additional expenses for monitoring and testing further fuel the debate. The risks associated with ARIA, particularly in the early stages of Alzheimer’s, underscore the need for more comprehensive data to guide treatment decisions.
As discussions continue, the broader question remains whether amyloid-clearing drugs like lecanemab and the recently approved donanemab can deliver long-term benefits and how they will fit into future Alzheimer’s treatments, possibly in combination with other therapies.
