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

Phase 1
Completed
Conditions
Hunter Syndrome
Interventions
Drug: Idursulfase-IT
Registration Number
NCT01506141
Lead Sponsor
Shire
Brief Summary

This extension study of HGT-HIT-045 is designed to collect long-term safety data in pediatric participants with Hunter syndrome and cognitive impairment who are receiving intrathecal (IT) idursulfase-IT and intravenous (IV) Elaprase enzyme replacement therapy.

Detailed Description

Not available

Recruitment & Eligibility

Status
COMPLETED
Sex
Male
Target Recruitment
25
Inclusion Criteria
  • Participant must have completed all study requirements and End of study (EOS) assessments for study HGT-HIT-045 (NCT00920647) prior to enrolling in Study HGT-HIT-046 and must have no safety or medical issues that contraindicate participation.
  • 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 assent, as relevant, must be obtained.
  • The participant 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
  • The participant is enrolled in another clinical study that involves clinical investigations or use of any investigational product (drug or device) other than the PORT-A-CATH IDDD within 30 days prior to study enrollment or at any time during the study.

  • The participant 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.

  • The participant has experienced an adverse reaction to study drug in Study HGT-HIT-045 (NCT00920647) that contraindicates further treatment with intrathecal idursulfase-IT.

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

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

  • The participant has a condition that is contraindicated as described in the SOPH-A-PORT Mini S 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 one 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

      An additional exclusion criterion for patients who were previously untreated with intrathecal idursulfase-IT in Study HGT-HIT-045 (NCT00920647):

  • The participant has an opening CSF pressure upon lumbar puncture that exceeds 30.0 centimeter (cm) water (H2O).

Study & Design

Study Type
INTERVENTIONAL
Study Design
SINGLE_GROUP
Arm && Interventions
GroupInterventionDescription
Idursulfase-ITIdursulfase-ITIdursulfase-IT will be administered once monthly and weekly IV infusions of Elaprase at the dose used in study HGT-HIT-045 via intrathecal drug delivery device (IDDD).
Idursulfase-ITElapraseIdursulfase-IT will be administered once monthly and weekly IV infusions of Elaprase at the dose used in study HGT-HIT-045 via intrathecal drug delivery device (IDDD).
Primary Outcome Measures
NameTimeMethod
Number of Participants With Treatment-emergent Adverse Events (TEAEs)From start of study drug administration up to follow-up (169 months)

An adverse event (AE) is any noxious, pathologic, or unintended change in anatomical, physiologic, or metabolic function as indicated by physical signs, symptoms, and/or laboratory changes occurring in any phase of a clinical trial, and whether or not considered study drug-related. Treatment-emergent AEs are defined as all AEs occurring on or after the first IDDD surgery date or first dose (whichever is earlier) for the participant (whether it is in this extension study or in HGT HIT-045 \[NCT00920647\]) and before the end of the study (EOS) visit (+30 days).

Secondary Outcome Measures
NameTimeMethod
Area Under the Curve Extrapolated to Infinity (AUC0-infinity) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours (h) following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Area under the curve extrapolated to infinity, calculated using the observed value of the last non-zero concentration (AUC0-infinity) of idursulfase will be assessed.

Area Under the Curve From the Time of Dosing to the Last Measureable Concentration (AUC0-t) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Area under the curve from the time of dosing to the last measureable concentration (AUC0-t) of idursulfase will be assessed.

Maximum Observed Concentration (Cmax) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Maximum Observed Concentration (Cmax) of idursulfase will be assessed.

First Order Rate Constant (Lambda z) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

First order rate constant (Lambda z) of idursulfase will be assessed.

Terminal Half-life (t1/2) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Terminal half-life (t1/2) of idursulfase will be assessed.

Time of Maximum Observed Concentration (tmax) of Idursulfase Administered in as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Time of maximum observed concentration (tmax) of idursulfase will be assessed.

Total Body Clearance for Extravascular Administration Divided by the Fraction of Dose Absorbed (Cl/F) of Idursulfase-IT Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Total body clearance for extravascular administration divided by the fraction of dose absorbed (Cl/F) of idursulfase will be assessed.

Volume of Distribution Associated With the Terminal Slope Following Extravascular Administration Divided by the Fraction of Dose Absorbed (Vz/F) of Idursulfase Administered as Intrathecal and in Conjunction With Elaprase15 minutes prior to IT injection, 1, 2, 3, 4, 6, 8, 12, 24, 30 and 36 hours following IT injection on Weeks 3 and 23, Day 2 of Months 19, 31, and 43

Volume of distribution associated with the terminal slope following extravascular administration divided by the fraction of dose absorbed (Vz/F) of idursulfase will be assessed.

Total Body Clearance (Cl) of Elaprase15 minutes prior to IV infusion, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 9, 11, and 24 hours during/after the IV infusion on Weeks 3 and 23

Total body clearance (Cl) of Elaprase will be assessed.

Volume of Distribution (Vz) of Elaprase15 minutes prior to IV infusion, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 9, 11, and 24 hours during/after the IV infusion on Weeks 3 and 23

Volume of distribution associated with the terminal slope (Vz) of Elaprase will be assessed.

Observed Steady-state Volume of Distribution (Vss) of Elaprase15 minutes prior to IV infusion, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 9, 11, and 24 hours during/after the IV infusion on Weeks 3 and 23

Observed steady-state volume of distribution (Vss) of Elaprase will be assessed.

Mean Residence Time (MRT) of Elaprase15 minutes prior to IV infusion, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 7, 9, 11, and 24 hours during/after the IV infusion on Weeks 3 and 23

Mean residence time (MRT) of Elaprase will be assessed.

Change From Baseline in CSF BiomarkersBaseline, Day 2 of Week 1, Day 2 Pre dose on Weeks 3, 7, 11, 15, 19, 23, 27, Months 7 - 169

Change from baseline in CSF biomarkers glycosaminoglycan (GAG \[HS/DS\]) will be assessed.

Change From Baseline in Urinary Glycosaminoglycan (GAG)Baseline, Day 1 Predose on Weeks 3, 7, 11, 15, 19, 23, 27, Months 7 - 169

Change from baseline in urinary GAG will be assessed.

Trial Locations

Locations (9)

British Columbia Children's Hospital

🇨🇦

Vancouver, British Columbia, Canada

Birmingham Children's Hospital

🇬🇧

Birmingham, United Kingdom

Ann & Robert H Lurie Childrens Hospital of Chicago

🇺🇸

Chicago, Illinois, United States

University of North Carolina at Chapel Hill

🇺🇸

Chapel Hill, North Carolina, United States

Legacy Emanuel Hospital

🇺🇸

Portland, Oregon, United States

Children's Hospital of Pittsburgh of UPMC

🇺🇸

Pittsburgh, Pennsylvania, United States

Vanderbilt Children's Hospital

🇺🇸

Nashville, Tennessee, United States

University of Utah Hospital

🇺🇸

Salt Lake City, Utah, United States

Seattle Children's Hospital

🇺🇸

Seattle, Washington, United States

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