Observational Study to Evaluate Neurodevelopmental Status in Pediatric Patients With Hunter Syndrome (MPS II)

Hunter syndrome (Mucopolysaccharidosis II, \[MPS II\]) is a rare, genetically linked lysosomal storage disease (LSD) caused by deficiency of the enzyme, iduronate-2-sulfatase (I2S). Most MPS II patients will present with some degree of neurodevelopmental involvement, ranging from severe cognitive impairment and behavioral problems to mildly impaired cognition. This is an observational study; no investigational treatment will be administered. The primary objective of this study is to evaluate the neurodevelopmental status of pediatric patients with MPS II over time and to gain information to guide future treatment studies in this patient population.