pp-215 Solution for injection

Indication: Rett syndrome — severe X-linked neurodevelopmental disorder caused by MECP2 loss-of-function mutations Clinical stage: Phase 2/3 Modality: Biological (AAV9 gene therapy delivering MECP2 gene with auto-regulatory miRNA — NBE) Mechanism / Target: AAV9 intrathecal vector delivering functional MECP2 transgene with embedded auto-regulatory miRNA sequence; miRNA senses endogenous MECP2 levels and self-limits transgene expression to prevent overexpression toxicity; restores MECP2 protein function in neurons; addresses root genetic cause of Rett syndrome Route / form: Intrathecal injection (single-dose, one-time treatment) Differentiation: Only MECP2 gene therapy with built-in auto-regulatory dosage control (prevents overexpression-related toxicity seen in other MECP2 gene therapy attempts);