Do newer Alzheimer’s treatments that remove amyloid actually preserve memory and independence, and what are their risks?

Lecanemab and donanemab do more than change a brain scan: randomized trials in selected people with early symptomatic Alzheimer’s disease found slower average decline on cognitive and functional scales. In CLARITY AD, the 18-month worsening on the 18-point CDR-SB scale was 1.21 points with lecanemab versus 1.66 with placebo, a 0.45-point difference. Both groups still worsened. Donanemab also slowed decline in its trial, but the percentages cannot be compared directly across different populations and endpoints. These are modest disease-slowing effects, not recovered memories or guaranteed preservation of independence.[1][2]

Eligibility and safety are central to the decision. Treatment is initiated in early disease with confirmed amyloid pathology, not for ordinary forgetfulness. These antibodies can cause amyloid-related imaging abnormalities, including brain swelling and bleeding; serious and fatal events can occur. Risk is higher in people with two APOE ε4 copies, and anticoagulant use and existing brain-imaging findings require careful consideration. Baseline and follow-up MRI monitoring are part of treatment. Potential benefit must therefore be weighed against individual risk, treatment burden and what matters to the patient and family.[3][4]