Prevention trial tests Alzheimer’s drug before symptoms appear

The first European participants in a major Alzheimer’s prevention trial are due to begin screening through an NHS trust on Monday.

Alzheimer’s-related changes can develop years before memory problems appear. Researchers want to learn whether treating people during that silent period can delay or prevent dementia, rather than waiting for symptoms.

The Phase 3 PrevenTRON study plans to recruit about 1,600 people aged 55 to 80. UK volunteers without memory problems will receive a blood test for p-tau217, a marker linked to future cognitive decline. Eligible higher-risk participants will be randomly assigned to the experimental drug trontinemab or a placebo and monitored for four to six years. Earlier research found the drug cleared amyloid plaques in nine out of ten people with early Alzheimer’s or mild cognitive decline within 28 weeks.

Plaque removal provides a reason to test earlier treatment, but it does not prove dementia can be prevented. The medicine remains investigational, and benefits and risks in symptom-free people are unknown.

At least 15 UK hospitals and clinics are expected to join by year-end as recruitment and monitoring expand.