Mucopolysaccharidosis Type II Observational

• Sponsor: REGENXBIO, Inc. (Industry)
• Overall Status: Recruiting
• CT.gov ID: NCT04591834
• Collaborator: (none)
• Enrollment: 40
• Locations: 3
• Anticipated Duration (Months): 42
• Patients Per Site: 13.3
• Patients Per Site Per Month: 0.3

Study Details

Study Description

Brief Summary

This is an observational study planned to document prospectively disease manifestation and neurocognitive course in pediatric patients with a clinical presentation consistent with neuronopathic ("severe") MPS II undergoing current standard of care and/or intrathecal Elaprase® for their condition. Some patients may be offered the opportunity to screen for a gene therapy study conducted by the same sponsor.

Condition or Disease	Intervention/Treatment	Phase
Mucopolysaccharidosis II	Other: Observational

Detailed Description

MPS II is a rare X-linked recessive genetic disease caused by mutations in the iduronate-2-sulfatase gene (IDS). Enzyme replacement therapy (ERT) with recombinant idursulfase (ELAPRASE®) is the only approved product for the treatment of Hunter syndrome; however, ERT as currently administered does not cross the blood brain barrier and is therefore unable to address the unmet need in MPS II patients with CNS (neurocognition and behavior) involvement. This is an observational study to document prospectively disease manifestation and neurocognitive course in pediatric patients with a clinical presentation consistent with neuronopathic ("severe") MPS II undergoing current standard of care for their condition. Approximately forty pediatric subjects who have severe MPS II will be enrolled. Changes in neurodevelopmental parameters of cognitive, behavioral, and adaptive function over time will be the primary focus for a duration of 104 weeks.

Study Design

• Study Type: Observational
• Anticipated Enrollment: 40 participants
• Observational Model: Other
• Time Perspective: Prospective
• Official Title: A Prospective, Observational Study of Pediatric Patients With Neuronopathic Forms of MPS II (Hunter Syndrome)
• Anticipated Study Start Date: Jan 1, 2022
• Anticipated Primary Completion Date: Jul 1, 2025
• Anticipated Study Completion Date: Jul 1, 2025

Arms and Interventions

Arm	Intervention/Treatment
Observational No Intervention	Other: Observational; An observational study in subjects with the severe form of MPS II.

Outcome Measures

Primary Outcome Measures

1. Changes in neurodevelopmental parameters of cognitive function over time [104 weeks]

   Bayley Scales of Infant and Toddler Development Third Edition (BSID-III)

2. Changes in neurodevelopmental parameters of cognitive function over time [104 weeks]

   Mullen Scales of Early Learning (MSEL) Visual Reception Domain

3. Changes in neurodevelopmental parameters of adaptive behavior function over time [104 weeks]

   Vineland Adaptive Behavior Scales Second Edition (VABS-II)

Secondary Outcome Measures

1. Changes in disease-specific biomarkers over time [104 weeks]

   I2S activity

2. Changes in disease-specific biomarkers over time [104 weeks]

   GAGs

3. Changes in quality of life [104 weeks]

   PedsQL

4. Changes in quality of life [104 weeks]

   ADL

5. Changes in Caregiver reported outcome [104 weeks]

   Family Burden of Illness Survey

6. Changes in sleep [104 weeks]

   SDSC

Eligibility Criteria

Criteria

• Ages Eligible for Study: 1 Month to 8 Years
• Sexes Eligible for Study: Male
• Accepts Healthy Volunteers: No

Inclusion Criteria:

1. Meets any of the following criteria:

2. Has a clinical diagnosis of severe MPS II and has a documented mutation in IDS, OR

3. Has a relative clinically diagnosed with severe MPS II who has the same IDS mutation as the subject, OR

4. Has documented mutation(s) in IDS that in the opinion of the investigator is known to result in a neuronopathic phenotype

5. Has sufficient communication capacity to complete the required protocol testing

Patient's legal guardian must be willing and able to provide written, signed informed consent.

Exclusion Criteria:

1. Has had prior treatment with an AAV-based gene therapy product

2. Is currently participating in a clinical trial of an investigational product for the treatment of MPS II with the exception of IT ELAPRASE trials; no investigational product may be taken starting 30 days or 5 half-lives of the investigational product prior to signing the ICF, whichever is longer

Contacts and Locations

Locations

	Site	City	State	Country	Postal Code
1	University of California San Francisco, Benioff Children's Hospital	Oakland	California	United States	94609
2	Children's Hospital of Philadelphia	Philadelphia	Pennsylvania	United States	19104
3	McGill University Health Center	Montréal	Quebec	Canada	H4A 3J1

Sponsors and Collaborators

• REGENXBIO, Inc.

Investigators

None specified.

Study Documents (Full-Text)

None provided.

More Information

Publications

None provided.

• Responsible Party: REGENXBIO, Inc.
• ClinicalTrials.gov Identifier: NCT04591834
• Other Study ID Numbers: RGX-121-9101
• First Posted: Oct 19, 2020
• Last Update Posted: Jan 21, 2022
• Last Verified: Jan 1, 2022

• Studies a U.S. FDA-regulated Device Product: No
• Keywords provided by REGENXBIO, Inc.: MPS II; Gene Therapy; Hunter
• Additional relevant MeSH terms: Mucopolysaccharidosis II; Mucopolysaccharidoses

Study Results

No Results Posted as of Jan 21, 2022