Natural History Study of Patients With Mucopolysaccharidosis Type IIIB (MPS IIIB, Sanfilippo Syndrome Type B)

This is a multicenter longitudinal, prospective, natural history study of patients with MPSIIIB designed to identify potential surrogate endpoints that may be utilized in future Enzyme replacement therapy (ERT) trials of MPS IIIB via defined assessments including standardized clinical, biochemical, neurocognitive, development, and imaging measures.