https://www.scientificamerican.com/article/experimental-alzheimers-drug-significantly-slowed-patients-cognitive-decline/

An investigational Alzheimer’s drug significantly slowed patients’ cognitive decline in a large clinical trial, unexpected and unprecedented results that could move the treatment’s makers to roll the dice on an early approval.

In the study, the highest-tested dose of a drug from Biogen and Eisai was markedly better than placebo at delaying the memory-destroying effects of Alzheimer’s. After 18 months, patients who got the drug, called BAN2401, performed 30 percent better on a cognitive test than those getting placebo.