Japan-based pharmaceutical company Eisai said Tuesday its latest experimental Alzheimer's drug, known as lecanemab, slowed cognitive decline in people who are in the early stages of the illness.
Eisai (ticker: ESALY), which is working with Biogen (BIIB) on the drug, said the Phase 3 trial slowed the rate of cognitive decline by 27% after 18 months compared with patients who had been given a placebo.
An effective treatment for the millions of people who have Alzheimer would be a breakthrough after the two companies' earlier drug, Aduhelm, got approval from the Food and Drug Administration but stalled because Medicare wouldn't pay for it.
Morgan Stanley estimated in July that the U.S. market opportunity for drugs like lecanemab is more than $20 billion.