Clinical Research Directory

Inclusion Criteria: * Age \< 5 years old * Confirmed diagnosis of SPG50 disease by: * Genomic DNA mutation analysis demonstrating homozygous or compound heterozygous, pathogenic and/or potentially pathogenic variants in the AP4M1 gene * Clinical history or examination features consistent with SPG50 and that include neurologic dysfunction * Parent/legal guardian willing to provide written informed consent for their child prior to participation in the study * Subject able to comply with all protocol requirements and procedures Exclusion Criteria: * Inability to participate in study procedures (as determined by the site investigator) * Presence of a concomitant medical condition that precludes lumbar puncture (LP) or use of anesthetics * History of bleeding disorder or any other medical condition or circumstance in which lumbar puncture is contraindicated according to local institutional policy * Inability to be safely sedated in the opinion of the clinical anesthesiologist * Active infection, at the time of dosing, based on clinical observations * Concomitant illness or requirement for chronic drug treatment that in the opinion of the PI creates unnecessary risks for gene transfer * Inability of the patient to undergo MRI according to local institutional policy * Inability of the patient to undergo any other procedure required in this study * The presence of significant non-SPG50 related central nervous system (CNS) impairment or behavioral disturbances that would confound the scientific rigor or interpretation of results of the study * Have received an investigational drug within 30 days prior to screening or plan to receive an investigational drug (other than gene therapy) during the study. * Enrollment and participation in another interventional clinical trial * Contraindication to MELPIDA or any of its ingredients * Contraindication to any of the immune suppression medications used in this study * Clinically significant abnormal laboratory values (GGT, ALT, and AST, or total bilirubin \> 3 × Upper Limit of Normal (ULN), creatinine ≥ 1.5 mg/dL, hemoglobin \[Hgb\] \< 6 or \> 20 g/dL; white blood cell (WBC) \> 20,000 per cmm) prior to gene replacement therapy. Patients with an elevated bilirubin level that is unequivocally the result of neonatal jaundice shall not be excluded