New research in Gene Therapy mapped AAV2 capsid clearance and neuronal trafficking dynamics within the central nervous system, highlighting processes that can constrain both safety and efficacy for gene-delivery programs. The study focused on what happens after capsids enter the CNS environment, including how they move and how clearance pathways limit persistence. For CNS-directed AAV therapies, the observed trafficking and clearance behavior matters because it can influence effective transduction rates and exposure duration in relevant neuronal populations. Understanding these pathways can also inform vector engineering strategies and study design. The report adds mechanistic detail to a recurring challenge in CNS gene therapy: translating dose and biodistribution findings into consistent functional outcomes. Overall, the work underscores the value of direct in vivo observation for viral vector performance rather than relying solely on peripheral biodistribution metrics.