Experimental anti-amyloid treatment, solanezumab, did not significantly slow Alzheimer’s- related cognitive decline in older adults. The corresponding trial, known as the ‘A4 Study’, was sponsored by Eli Lilly and Company.
For the study, the researchers enrolled 1150 participants aged between 65 and 85 years old. At the beginning of the trial in 2013, all participants had normal thinking and memory ability but evidence of elevated amyloid plaque accumulation- a buildup of protein in the brain- as identified by PET imaging. Amyloid plaque buildup begins many years before symptoms of Alzheimer's disease (AD) arise.
Participants were split into two groups, and either received a placebo or solanezumab every four weeks for four and a half years. In the end, the researchers found that solanezumab did not slow cognitive decline compared to the placebo. Amyloid PET imaging demonstrated that amyloid continued to accumulate in both placebo and solanezumab groups. Higher amyloid burden at the start of the study was linked to more rapid decline later on.
Co-principal investigator Reisa Sperling, MD, Director of the Center for Alzheimer Research and Treatment at Brigham and Women’s Hospital, is now working with collaborators on another study called ‘AHEAD 3-45 Study’ to investigating a different anti-amyloid antibody known as lecanemab.
“The A4 Study was successful in demonstrating the feasibility of conducting a large-scale trial in people with evidence of amyloid in their brain who do not yet have symptoms, and we are so grateful to our very dedicated participants,” she said in a press release.
“As we continue to analyze the data, we expect to learn much more about the factors that influence the rate of progression towards Alzheimer’s disease dementia,” she concluded.
Sources: Neuroscience News, Lilly.com