Preclinical Development of a Vectorized Artificial miRNA Gene Therapy for Tauopathies

Area of Science:

• Neuroscience
• Genetics
• Molecular Biology

Background:

• Tauopathies are neurodegenerative diseases characterized by tau protein accumulation, closely linked to cognitive decline.
• Reducing tau protein levels presents a promising therapeutic strategy for tau-linked brain disorders.

Purpose of the Study:

• To develop and evaluate a gene therapy approach for reducing tau protein using adeno-associated virus (AAV)-mediated delivery of artificial microRNA (amiRNA).
• To assess the efficacy of this vectorized tau-lowering strategy in a preclinical tauopathy mouse model.

Main Methods:

• Development of an AAV vector carrying an amiRNA targeting human tau.
• Intra-cisterna magna administration of the AAV vector in a tauopathy mouse model.
• Assessment of total tau levels, pathological tau seeds, tau inclusions, and neuropathology post-intervention.

Main Results:

• A single administration of the AAV vector significantly reduced total tau, pathological tau seeds, and tau inclusions.
• The intervention ameliorated tau-related neuropathology and improved quality of life and survival, even when administered at late disease stages.
• Durable therapeutic benefits were observed, and the minimally effective dose was determined.

Conclusions:

• Vectorized tau-lowering via AAV-mediated amiRNA delivery shows preclinical efficacy as a disease-modifying treatment for tauopathies.
• This strategy supports progression towards an investigational new drug application for treating tau-linked neurodegenerative disorders.