Long-term Metazym Treatment of Patients With Late Infantile Metachromatic Leukodystrophy (MLD)

Inclusion Criteria: The patients from the Phase I trial must meet the following criteria to be enrolled in the study. * Subject's legally authorized guardian(s) must provide signed, informed consent prior to performing any study-related activities (trial-related activities are any procedures that would not have been performed during normal management of the subject) * The subject and his/her guardian(s) must have the ability to comply with the clinical protocol Exclusion Criteria: * Spasticity so severe to inhibit transportation * Presence of known clinically significant cardiovascular, hepatic, pulmonary or renal disease or other medical condition that, in the opinion of the Investigator, would preclude participation in the trial * Any other medical condition or serious intercurrent illness, or extenuating circumstance that, in the opinion of the Investigator, would preclude participation in the trial * Use of any investigational product other than rhASA within 30 days prior to study enrolment or currently enrolled in another study which involves clinical investigations