New treatments for Alzheimer’s disease

Donanemab is a new monoclonal antibody treatment that binds to amyloid β to stimulate microglial removal of amyloid plaques from the brain in people with Alzheimer’s disease.1 In the recently published Trailblazer-ALZ 2 trial in 1736 adults with early symptomatic disease, participants treated with donanemab had a mean decline over 18 months that was 3.03 points less than those given placebo on a 144 point scale of cognition and functional ability (integrated Alzheimer disease rating scale (−6.02 v −9.27; difference 3.25, 95% confidence interval 1.88 to 4.62). All participants had evidence of brain amyloid and tau protein accumulation on positron emission tomography at recruitment.2 Of a further 24 secondary and exploratory trial outcomes, 23 showed statistically significant benefits with donanemab. Notably, the benefit on the mini-mental state examination was 0.48 points; patients with Alzheimer’s disease dementia typically show an annual decline of 3 points on this measure.3

The …