An Open-label Study to Evaluate Safety and Preliminary Efficacy of a Single Intracerebroventricular Injection of HG204 for MECP2 Duplication Syndrome in Males Aged 2 to 18

What this Trial Is About

MECP2 Duplication Syndrome (MDS) is a rare genetic disorder mostly affecting males, causing severe intellectual disability, motor problems, low muscle tone in infancy, epilepsy, frequent respiratory infections, and often leading to early death before age 25. This condition is caused by extra copies of the MECP2 gene, which is important for brain development and function. Researchers are studying HG204, a new CRISPR RNA-editing therapy designed to reduce the levels of MECP2 protein in the brain and improve symptoms in affected individuals. HG204 uses a special technology called high-fidelity Cas13Y delivered by a single adeno-associated virus vector. The therapy is given as a single injection directly into the brain's ventricles. The study plans to evaluate two dose groups to assess safety and effectiveness. The treatment phase includes a screening period of 8 weeks, followed by the injection visit and a 52-week follow-up to monitor effects and safety. Participants will be closely monitored during this study lasting about 60 weeks, including initial screening, treatment, and follow-up visits. Researchers will track any side effects and changes in clinical status using various developmental and behavioral assessments. Laboratory tests and imaging will be used to evaluate health status, and the primary outcome is the incidence and severity of adverse events over 52 weeks. The study aims to gather detailed information on the safety and potential benefits of HG204 for patients with MDS.

A First-in-Human Clinical Trial to Evaluate the Safety, Tolerability, and Efficacy of a Novel CRISPR RNA-editing Therapy in Patients with Mecp2 Duplication Syndrome, a Rare Orphan Disease (HERO)