Extension of HGT-HIT-045 Evaluating Long-Term Safety and Clinical Outcomes of Idursulfase (IT)in Conjunction With Elaprase in Pediatric Patients With Hunter Syndrome and Cognitive Impairment

Inclusion Criteria:

• Patient must have completed all study requirements and end of study assessments for study HGT-HIT-045 prior to enrolling in Study HGT-HIT-046 and must have no safety or medical issues that contraindicate participation.
• The patient's parent(s) or legally authorized guardian(s) must have voluntarily signed an Institutional Review Board (IRB)/Independent Ethics Committee(IEC)-approved informed consent form after all relevant aspects of the study have been explained and discussed. Consent of the patient's parent(s) or legally authorized guardian(s) and the patient's assent, as relevant, must be obtained.
• That patient has received and tolerated a minimum of 12 months of treatment with weekly IV infusions of Elaprase and has received 80% of the total planned infusions within the last 6 months.

Exclusion Criteria:

• Patient has received treatment with any investigational drug (other than idursulfase-IT) or device within 30 days prior to study entry.
• Patient is unable to comply with the protocol (eg, is unable to return for safety evaluations, or is otherwise unlikely to complete the study) as determined by the investigator.
• Patient has experienced an adverse reaction to study drug in Study HGT-HIT-045 that contraindicates further treatment with intrathecal idursulfase-IT.
• Patient has a known hypersensitivity to any of the components of idursulfase-IT.
• For patients who were previously untreated with intrathecal idursulfase-IT in Study HGT-HIT-045, the patient has an opening CSF pressure upon lumbar puncture that exceeds 30.0 cm H2O