Study of Long Term Safety and Clinical Outcomes of Idursulfase IT and Elaprase Treatment in Pediatric Participants Who Have Completed Study HGT-HIT-094

An Open Label Extension of Study HGT-HIT-094 Evaluating Long Term Safety and Clinical Outcomes of Intrathecal Idursulfase Administered in Conjunction With Elaprase® in Patients With Hunter Syndrome and Cognitive Impairment

This extension study will allow participants that completed Study HGT-HIT-094 to continue receiving Elaprase treatment in conjunction with idursulfase IT or to continue receiving Elaprase treatment and begin concurrent IT treatment for those that did not receive idursulfase IT treatment in Study HGT-HIT-094.

Inclusion Criteria:

• Participants must have completed Visit Week 52 assessments in Study HGT-HIT-094 (NCT02055118).
• The participant'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 participant's parent(s) or legally authorized guardian(s) and the participant's consent/assent, as relevant, must be obtained.
• The participant has continued to receive Elaprase on a regular basis in Study HGT-HIT-094 (NCT02055118).

Exclusion Criteria:

• The participant has experienced, in the opinion of the investigator, a safety or medical issue that contraindicates treatment with idursulfase-IT, including, but not limited to, uncontrolled seizure disorder, bleeding disorder, and clinically relevant hypertension.

• The participant has a known hypersensitivity to any of the components of idursulfase-IT.

• The participant has clinically relevant intracranial hypertension.

• The participant is enrolled in another clinical study, other than HGT-HIT-094 (NCT02055118), that involves clinical investigations or use of any investigational product (drug or [intrathecal/spinal] device) within 30 days prior to study enrollment or at any time during the study.

• The participant has any known or suspected hypersensitivity to anesthesia or is thought to be at an unacceptably high risk for anesthesia due to compromised airways or other conditions.

• The participant has a condition that is contraindicated as described in the SOPH-A-PORT® Mini S, Implantable Access Port, Spinal, Mini Unattached, with Guidewire (SOPH-A-PORT Mini S) intrathecal drug delivery device (IDDD) Instructions for Use, including:

  1. The participant has had, or may have, an allergic reaction to the materials of construction of the SOPH-A-PORT Mini S device.
  2. The participant's body size is too small to support the size of the SOPH-A-PORT Mini S Access Port, as judged by the investigator.
  3. The participant's drug therapy requires substances known to be incompatible with the materials of construction.
  4. The participant has a known or suspected local or general infection.
  5. The participant is at risk of abnormal bleeding due to a medical condition or therapy.
  6. The participant has 1 or more spinal abnormalities that could complicate safe implantation or fixation.
  7. The participant has a functioning CSF shunt device.
  8. The participant has shown an intolerance to an implanted device.