This clinical trial is focused on studying the long-term safety of a treatment for Hunter Syndrome, a rare genetic disorder that affects the body’s ability to break down certain sugars. The study involves patients who also have cognitive impairment, which means they experience difficulties with thinking and understanding. The treatment being tested is called Idursulfase, specifically in a form known as idursulfase-IT (HGT-2310), which is administered directly into the spinal fluid through a method called intrathecal injection. This is done using a special device called the SOPH-A-PORT Mini S Implantable access port. In addition to this, patients will continue to receive Elaprase, an enzyme replacement therapy given through an intravenous (IV) infusion.

The purpose of the study is to gather information on the long-term safety of this combined treatment approach. Participants in this study have previously been involved in earlier studies and have shown clinical benefits from the treatment. The study will monitor the safety of the treatment by observing any side effects or adverse events that may occur, including those related to the medication, the device used for administration, and the procedure itself.

Throughout the study, participants will receive regular doses of the treatment and will be closely monitored by healthcare professionals. The study aims to ensure that the treatment is safe for long-term use in individuals with Hunter Syndrome and cognitive impairment. This research is important for understanding how to best manage and treat this condition over an extended period.