URGENT: U.S. formally approves Alzheimer’s drug developed by Japan’s Eisai

U.S. regulators on Thursday formally approved an Alzheimer’s drug developed by Japanese pharmaceutical company Eisai Co. and U.S. firm Biogen Inc. that has become the world’s first medicine shown to slow down the early stages of the degenerative brain disease.

The Food and Drug Administration granted its approval for the new drug, known chemically as lecanemab, which can reduce the amount of a sticky brain protein called amyloid beta, seen by experts as a hallmark of the disease.