A patient receiving Eisai and Biogen's jointly-developed investigational mAb for Alzheimer’s disease suffered a deadly brain hemorrhage, Science reported this week.
The clinical trial death is thought to be the second one related to the anti-amyloid beta protofibril antibody. The drug, lecanemab, is being studied for the treatment of mild cognitive impairment due to Alzheimer’s disease and early Alzheimer’s disease with confirmed presence of amyloid pathology in the brain.
As outlined in an unpublished case report obtained by Science, the 65-year-old woman had received infusions of the antibody as a part of the trial and initially suffered a stroke and a specific type of bleeding and swelling that is expected with similar treatments. The woman was seen at the Northwestern University Medical Center in Chicago and was given a tissue plasminogen activator, but she suffered bleeding in the brain’s outer layer and died a few days later.
The case report, which was co-written by a neuropathologist at Northwestern who performed the autopsy, concluded that the patient had significant amyloid deposits. The physician, Rudolph Castellani, said to Science that their opinion was that “This is a treatment-caused illness and death. If the patient hadn’t been on lecanemab she would be alive today.”
The phase 3 trial in which she was participating, called Clarity AD, has roughly 1800 people enrolled. Back in Sept., the partners announced that the trial met the primary endpoint and all key secondary endpoints with highly statistically significant results. The primary endpoint, Clinical Dementia Rating-Sum of Boxes (CDR-SB), is a numeric scale used to quantify the various severity of symptoms of dementia.
The first trial death — reported by STAT News back in Oct. — involved a man in his late 80s who died of a brain hemorrhage that was thought to be linked to an interaction between lecanemab and the blood thinner Eliquis.
Lecanemab's PDUFA date is set for January 6, 2023.
