Alzheimer Disease Trial Terminated Early Due to Futility and Adverse Events

Alzheimer disease (AD) is a progressive neurodegenerative illness affecting cognition and behavior, associated with characteristic neuropathological changes including tau tangles and amyloid-beta plaques. Semagacestat is an investigational drug that functionally inhibits the action of gamma secretase on the amyloid precursor protein, an important step in the amyloid cascade of plaque deposition in the brain, which presumably is associated with the development of clinical symptoms. Phase 1 and 2 semagacestat data suggested a dose-dependent decrease in plasma amyloid-beta levels but no reduction in amyloid-beta levels in cerebrospinal fluid (CSF) in humans.

Investigators conducted this multinational, phase 3, double-blind, randomized, manufact…