Alzheimer's disease (AD) is an irreversible brain disorder associated with 
severe progressive dementia and is characterized by deposits of amyloid plaques 
in the brain. Over the past 20 years, the mortality of strokes and heart disease 
has decreased, but deaths from AD have increased. The four drugs used clinically 
to treat AD can only relieve symptoms but cannot slow the progression of the 
disease. Aducanumab, a human monoclonal antibody that preferentially binds to 
aggregated amyloid-β to reduce the number of amyloid plaques and slow disease 
progression, was approved to treat AD by the US Food and Drug Administration on 
June 7, 2021. It is the first disease-modifying therapy for AD, but there is 
considerable controversy regarding the drug's approval. Aducanumab offers hope 
for millions of patients.