Stem Cell Transplant w/Laronidase for Hurler

Phase 2

Completed

Brief Summary: The investigators hypothesize that weekly infusions of Laronidase ERT for 10-12 weeks prior to transplant and 8 weeks following transplant will result in a reduction of glycosaminoglycans (GAG) burden that is associated with decreased complications following transplant.

Detailed Description: Subjects will receive laronidase once a week intravenously for 10-12 weeks prior to transplant and for approximately 8 weeks after transplant. Laronidase will be given by intravenous infusion (IV) through a catheter and from there to your child's body's cells and organs to break down the glycosaminoglycans (GAG) buildup.

Prior to starting ERT, subjects will have a complete physical examination, which includes a complete assessment of your child's airway and lungs. In addition to standard treatment evaluations and tests, which are done prior to hematopoietic stem cell transplant (HSCT), subjects will have the following tests: an additional teaspoon of blood for a baseline test for serum antibodies against laronidase, before and after the fourth dose of laronidase, the investigators will collect 2 teaspoons of blood for an alpha-L-iduronidase enzyme level; to watch for side effects to laronidase and the development of antibodies to laronidase, approximately 2 teaspoons of blood will be collected every 3 weeks while the subject is receiving laronidase ERT.

Recruitment & Eligibility

Inclusion Criteria

Patients with the diagnosis of mucopolysaccharidosis type IH (MPS I, Hurler syndrome) who are candidates for first hematopoietic stem cell transplant (HSCT) according to a University of Minnesota myeloablative HSCT protocol.

Exclusion Criteria

Arm && Interventions

Group	Intervention	Description
Laronidase ERT Treatment	Laronidase ERT	Weekly infusion of laronidase enzyme replacement therapy followed by hematopoietic stem cell transplant.
Laronidase ERT Treatment	Stem Cell Transplant	Weekly infusion of laronidase enzyme replacement therapy followed by hematopoietic stem cell transplant.

Primary Outcome Measures

Name	Time	Method
Number of Patients Requiring Ventilator Support at One Year Post Transplant	one year
Number of Patients Alive at One Year Post Transplant	one year

Secondary Outcome Measures

Name	Time	Method
Donor Engraftment	Day 100 post transplant
Patients With Grade III-IV Acute GVHD	Day 100 post transplant
Reduction in Glycosaminoglycans (GAG)	Prior to, During and After ERT	Data was not collected on this outcome measure and is not available for reporting.
Toxicity (Adverse Events) Associated With Infusions of Laronidase	1 year post transplant	Data was not collected on this outcome measure and is not available for reporting.
Development of Anti-iduronidase Antibodies in Serum	1 Year
Patients With Improvement in Obstructive Apnea (Breathing) by Polysomnography	Baseline, 12 weeks after laronidase, after transplant