β-amyloid: The known unknowns

Area of Science:

• Neuroscience
• Neurology
• Biochemistry

Background:

• Alzheimer's disease (AD) lacks effective preventative or disease-modifying therapies.
• Numerous Phase 3 clinical trials targeting amyloid beta (Aβ) have failed to slow cognitive decline.
• The growing burden of AD necessitates urgent development of new therapeutic strategies.

Purpose of the Study:

• To critically re-evaluate the central role of amyloid beta (Aβ) in Alzheimer's disease pathogenesis.
• To question the fundamental assumptions underlying current anti-Aβ therapeutic approaches.
• To advocate for the investigation of alternative targets for AD treatment.

Main Methods:

• Review of existing pathology, genetic, and biochemical data related to AD.
• Analysis of findings that challenge the dominant amyloid cascade hypothesis.
• Critical examination of the evidence supporting Aβ as the primary driver of AD.

Main Results:

• Significant failures in 33 Phase 3 clinical trials targeting Aβ highlight limitations of this approach.
• Alternative explanations and dissenting findings regarding Aβ's role warrant deeper investigation.
• Current therapeutic strategies based on Aβ may be premised on flawed assumptions.

Conclusions:

• The field must consider shifting focus from solely targeting Aβ.
• Renewed interrogation into AD pathogenesis beyond the amyloid hypothesis is crucial.
• Exploring alternative targets is essential for developing effective disease-modifying therapies for Alzheimer's disease.