Neurodegenerative diseases are a diverse group of disorders characterized by the progressive degeneration of the central or peripheral nervous system, and they can have various causes and clinical characteristics. This guidance document is a resource for sponsors on different aspects of product development, preclinical testing, and clinical trial design. It acknowledges the unique challenges and considerations associated with developing GT products for such complex and varied diseases. Below are the key summaries from the guidance. CONSIDERATIONS FOR CHEMISTRY, MANUFACTURING AND CONTROLS (CMC) The considerations for Chemistry, Manufacturing, and Controls (CMC) when developing gene therapy (GT) products for the treatment of neurodegenerative diseases are crucial for ensuring the safety and efficacy of these advanced therapies. Here, we will elaborate on the specific CMC considerations outlined in your text: Route of Administration and Product Volume: Neurodegenerative diseases often r