Spastic Paraplegia-50, Autosomal Recessive

Safety and Efficacy of AAV9/AP4B1 For Patients with AP4B1-related Hereditary Spastic Paraplegia Type 47 (SPG47): A Phase 1/2 Single-Center, Open-Label Study of Stereotactic Intra-cisterna Magna Administration.
The goal of this clinical trial is to evaluate whether a gene therapy can safely treat children with SPG47, a rare genetic condition that causes progressive spasticity and developmental delays. The main questions it aims to answer are:
* Is the gene therapy safe and well tolerated?
* Does the gene therapy improve motor function and developmental outcomes?
Participants will:
* Undergo screening assessments to confirm eligibility
* Receive a single dose of the gene therapy vector
* Attend follow-up visits for safety monitoring and developmental assessments over the course of five years

Phase 3, open-label study to assess the efficacy and safety of a single lumbar intrathecal administration of MELPIDA in individuals with Hereditary Spastic Paraplegia Type 50 (SPG50).

MELPIDA is proposed for the treatment of subjects with SPG50 and targets neuronal cells to deliver a fully functional human AP4M1 cDNA copy via intrathecal injection to counter the associated neuronal loss. Outcomes will evaluate the safety and tolerability of a single dose of MELPIDA, which will be measured by the treatment-associated adverse events (AEs) and serious adverse events (SAEs). Secondarily, the trial will explore efficacy in terms of disease burden assessments.