Comparative analysis of FDA-approved Alzheimer’s therapies: symptomatic and disease-modifying approaches

Abstract

Alzheimer's disease (AD) is a progressive neurodegenerative disorder primarily affecting the elderly and the most common cause of dementia, characterized by neuronal loss, cognitive decline, and memory impairment. Several FDA-approved medications for AD fall into two main categories: symptomatic treatments and disease-modifying therapies. Symptomatic treatments include acetylcholinesterase inhibitors and N-methyl-d-aspartate (NMDA) receptor antagonists. These drugs help mitigate cognitive decline: cholinesterase inhibitors increase acetylcholine levels, whereas NMDA receptor antagonists regulate glutamate activity. Disease-modifying therapies treat the disease pathology by reducing the amyloid-beta plaque burden. These are monoclonal antibody therapies such as Aducanumab, Lecanemab, and Donanemab, the latter as a monthly intravenous infusion until the plaques can no longer be detected. This review provides a comparative analysis of symptomatic and disease-modifying therapies, focusing on their pharmacokinetics, characteristics, mechanisms of action, clinical efficacy, side effects, and recent trial findings.

Keywords

• Alzheimer’s disease
• symptomatic therapy
• disease-modifying therapy
• acetylcholinesterase inhibitors
• N-methyl-d-aspartate receptor antagonists
• monoclonal antibodies
• amyloid-beta
• tau pathology

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