By Kimberly Chin

Biogen Inc. and Eisai Co. said that a Phase 3 trial of its Alzheimer treatment yielded some positive results, including the reduction of tau pathology.

The companies said that the Aduhelm treatment, a monoclonal antibody that is directed against amyloid beta, was able to lower plasma p-tau181, a biomarker of the tau tangles found in those with Alzheimer's disease, in advanced trials in both a dose- and time-dependent setting.

The companies said the reduction in plasma p-tau181 was significantly correlated with less cognitive and functional decline from the disease. The plasma p-tau181 reduction was also correlated with the lowering of amyloid beta plaque.

Amyloid beta plaque and neurofibrillary tangles, which are made up of abnormal p-tau, are considered the hallmarks of Alzheimer's disease and can disrupt the communication between neurons, leading to the brain's decline.

Biogen and Eisai looked at data from about 7,000 plasma samples from over 1,800 patients in the trials. It presented its findings at the Clinical Trials on Alzheimer's Disease conference on Thursday.

Biogen's shares rose 2.4% after hours to $273.

Write to Kimberly Chin at kimberly.chin@wsj.com

(END) Dow Jones Newswires

11-11-21 1825ET