Gene Replacement Therapy for Treatment of Paediatric Patients With CTNNB1 Neurodevelopmental Syndrome

The goal of this first in human, phase I/II clinical trial is to evaulate the safety, tolerability, and preliminary efficacy of AAV9 mediated gene replacement therapy (Urbagen) in paediatric patients with CTNNB1 neurodevelopmental disorder. The main questions it aims to answer are: * Is the gene therapy with Urbagen safe and well tolerated? * Does the gene therapy improve motor function, cognitive function, behavior, sleep, and/or quality of life? Participants will: * Undergo screening assessments to ensure eligibility. * Recieve a single dose of gene therapy via bilateral intracerebroventricular administration. * Recieve prophylactic immunosuppresants (methylprednisolone, sirolimus). * Attend follow-up visits for safety monitoring and clinical assessments over the course of three years.

NCT Number	NCT07270549
Lead Sponsor	CTNNB1 Foundation Collaborators: University Medical Centre Ljubljana
Conditions	CTNNB1 Neurodevelopmental Syndrome
Enrollment	12 participants
Start Date	2025-11-01
Primary Completion	2032-12-31 (estimated)
Study Completion	2032-12-31 (estimated)
Updated on ClinicalTrials.gov	2026-03-25