Aug 28 (Reuters) - The U.S. Food and Drug Administration

said on Thursday it is recommending additional, earlier scans to

monitor brain swelling prior to the third infusion for patients

with Alzheimer's disease taking Eisai ( ESALF ) and Biogen's

drug Leqembi.

The earlier monitoring can identify individuals with

amyloid-related imaging abnormalities with edema (ARIA-E), which

is characterized by brain swelling or fluid buildup.

The FDA said it identified six deaths early in treatment,

which prompted an in-depth analysis of serious and fatal

outcomes related to ARIA-E before the fifth Leqembi infusion.

The health regulator said it is requiring the prescribing

information of Leqembi to include an earlier monitoring between

the second and third infusion.

The companies did not immediately respond to a Reuters

request for comment.

The current prescribing information of Leqembi recommends

MRI imaging before the fifth, seventh and 14th infusions.

The health regulator requires patients on rival Eli Lilly's ( LLY )

Alzheimer's drug Kisunla to obtain a brain MRI prior to

the second, third, fourth and seventh infusions.

Biogen's Leqembi was approved in 2023 to slow the

progression of Alzheimer's disease in patients with mild

cognitive impairment or mild dementia stage of disease.

It targets an underlying cause of the fatal mind-wasting

disease.

An injectable version of the drug, currently given by

intravenous infusion, is under U.S. regulatory review.