Fibroblast-derived Engineered Extracellular Vesicle (FieEV) Technology for Targeted Delivery of RNA Therapeutics to treat CMT1A Diseases

Summary Charcot-Marie-Tooth disease type 1A (CMT1A) is a genetic neuromuscular disorder that affects around 1 in 5,000 people worldwide. The disorder is caused by the duplication of the peripheral myelin protein 22 (PMP22) in Schwann cells (SCs). The overexpression of PMP22 protein leads to SCs apoptosis, dys- and de-myelination and axonal degeneration, ultimately causing neurological disabilities. Viral-based approaches such as Adeno- associated Virus (AAV) gene therapy hold the potential to benefit individuals with CMT1A. However, AAV vectors have numerous limitations, including immunogenicity, which limits the capability to re-dose patients, limited cargo capacity, and insufficient tissue or cell type specificity, which contribute to off-target effects. To overcome these limitations, Extracellular Vesicles (EVs) have emerged as a promising method for delivering therapeutic molecular cargo such as RNA, DNA and proteins. EVs are nanoparticles naturally released by cells that facilitated intercellular communication and molecular cargo transfer. EVs can package large molecular cargos, are biocompatible, show low immunogenicity allowing re-dose patients, and can pass through biological barriers, making them more versatile than most other carrier systems, both viral and synthetic such as lipid nanoparticles (LPNs). While interest in the use of EVs for drug delivery has grown significantly over the past few years we are not aware of examples promoting the development of EV-based gene therapy to treat CMT1A. The purpose of this project is to refine our Fibroblast-Derived Engineering Extracellular Vesicles (FieEV) platform for RNA-based therapeutics as a novel non-viral delivery methods to address the limitations of RNA therapeutics for CMT1A. To achieve this goal, we will evaluate the effectiveness of the FieEV in delivery microRNA (miRNA) miR381 or miR871 to SCs in vitro and in vivo and optimize eEVs dose administration for future analysis. The successful completion of this project will support a Phase II application. During this phase, we will conduct in vivo dose optimization, assessment of efficacy and durability to validate our EV-based RNA Technologies. Our ultimate goal is to bring the FieEV therapy to the FDA for the first RNA EV-based clinical trials for use in peripheral nervous system (PNS) disorders.