Tau in Alzheimer's disease: Shaping the future patient journey

Alzheimer's disease is a complex and multifactorial disease characterized by two key pathological hallmarks: amyloid-beta plaques and tau neurofibrillary tangles. Recent progress has led to the development and approval of disease-targeted therapies for Alzheimer's disease in the form of anti-amyloid-beta monoclonal antibodies. However, findings suggest that amelioration of multiple pathological drivers may be required to maximize clinical effect. An increasing body of evidence suggests that tau is a critical player in Alzheimer's disease pathophysiology, contributing significantly to neurodegeneration and cognitive decline. There are now several tau-targeting drugs in clinical development. In this review, we build on research and advancements in the field of tau to envision how an increasing focus on tau could shape the future Alzheimer's disease patient journey. We highlight the potential of tau as both a promising therapeutic target and a valuable biomarker, with the potential to inform treatment decisions and provide insight into disease trajectories. We also consider what a greater focus on tau may bring to an already evolving patient care pathway characterized by an increased influx of patients presenting earlier in the disease continuum, changes in workflow and infrastructural requirements, and increased complexity in treatment decision-making, treatment administration, treatment monitoring, and patient tracking. This review underscores the critical changes that may be required and knowledge gaps to be elucidated to ensure healthcare system preparedness for additional classes of disease-targeted therapy to move toward a next-generation, individualized treatment approach to Alzheimer's disease diagnosis and care.