Gene therapy injection into the brain aims to treat rare genetic disorder

Copied word for word from the study's registry entry, so the wording is the study team's rather than ours.

Inclusion Criteria: * Age ≥3 years and \<18 years (at the time of signing informed consent), any gender * Genetic test and clinical confirmed diagnosis of SHANK3-related PMS * Meets diagnostic criteria for moderate or more severe Autism Spectrum Disorder (ASD) * Intelligence Quotient (IQ) score \<70 or Developmental Quotient (DQ) (excluding gross motor) average score \<70 * Willing to provide biological samples required for the study (e.g., blood, urine) * Consent to hospitalization for intracerebroventricular injection surgery * The holders of parental authority who are able to understand and willing to comply with study requirements and procedures, voluntarily participating and signing the informed consent Exclusion Criteria: A pediatric participant who meets any of the following criteria will be excluded from this study: * Previous or current participation in other PMS drug clinical trials or other AAV gene therapy clinical studies * Has known allergic constitution, including allergy or hypersensitivity to prednisone acetate, other glucocorticosteroids, their excipients, or local anesthetics * Subjects with status epilepticus within 3 months prior to enrollment * Subjects requiring invasive or non-invasive ventilatory support * Serum anti-AAV neutralizing antibody titer \>1:200 * Significant laboratory abnormalities: alanine aminotransferase (ALT), aspartate aminotransferase (AST), γ-glutamyl transferase (GGT) with any value above the upper limit of normal; total bilirubin above the upper limit of normal; creatinine ≥159 μmol/L; hemoglobin (Hb) \<80 g/L; prothrombin time (PT) prolonged by ≥3 seconds; activated partial thromboplastin time (APTT) prolonged by ≥10 seconds; fasting blood glucose ≥7.0 mmol/L; glycated hemoglobin (HbA1c) ≥6.5%; platelets (PLT) \<100×10\^9/L * Subjects with liver disease or history of heart disease that may pose drug-related risks as assessed by the investigator * Subjects deemed unsuitable for intracerebroventricular administration or with other special circumstances as assessed by the investigator * Positive for human immunodeficiency virus antibody, hepatitis B surface antigen, hepatitis C antibody, syphilis antibody, active TORCH virus infection, or active Epstein-Barr virus infection * Concomitant use of any of the following medications within 90 days prior to administration, or planned immunosuppressive treatment within 3 months after starting the trial, except for prophylactic medications specified in the protocol (cyclosporine, tacrolimus, methotrexate, cyclophosphamide, intravenous immunoglobulin, rituximab, etc. ) * Other conditions deemed unsuitable for participation in this study by the investigator