Launched in 2013, the A4 study was a double-blind and placebo-controlled Phase III study testing the anti-amyloid drug, solanezumab, in cognitively normal older people (65-85 years old) who had brain PET scans showing evidence of amyloid build-up. The study included more than 1.100 participants who were randomised to receive either solanezumab or placebo every four weeks during approximately 4.5 years. Earlier this year, the pharmaceutical company Eli Lilly reported that the trial failed to meet its primary goal of slowing cognitive decline in the Preclinical Alzheimer Cognitive Composite (PACC) score. Secondary clinical outcome results were consistent with the primary outcome. Solanezumab, which targets monomeric amyloid in people with elevated brain amyloid levels, did not slow cognitive decline as compared with placebo over a period of 240 weeks in persons with preclinical AD. Findings have been recently published in The New England Journal of Medicine:
