Open Questions On Safety Lingers After Eisai-Biogen's Detailed Lecanemab Data For Alzheimer's - Eisai Co (OTC:ESALF), Biogen (NASDAQ:BIIB)

According to detailed data, Eisai Limited ESALY and Biogen Inc's BIIB closely watched trial of an experimental Alzheimer's drug slowed cognitive decline but may carry a risk of side effects for certain patients.
Lecanemab was associated with a type of brain swelling in 12.6% of trial patients, a side effect previously seen with similar drugs.
17.3% of patients had microhemorrhages in the brain— a symptom linked to two recent deaths of people receiving lecanemab in a follow-on study.
Treatment with lecanemab reduced clinical decline on the global cognitive and functional scale by 27% at 18 months, relative to the placebo, the trial's primary endpoint.
Two deaths— both from brain hemorrhages— have been reported among participants in a trial extension - a 65-year-old woman who received a type of medicine known as tissue plasminogen activator to clear blood clots after a stroke and an 87-year-old who was on the blood thinner Eliquis.
Eisai said the two deaths "cannot be attributed to lecanemab."
The FDA is slated to decide by January 6 whether to approve lecanemab under its accelerated review program.
Price Action: BIIB shares are up 6.05% at $308.97 on the last check Wednesday.