Long Term Follow-Up for RGX-111

A Long-term Follow-up Study to Evaluate the Safety and Efficacy of RGX-111

RGX-111-5101 is a long-term follow up study that evaluates the long term safety and efficacy of RGX-111 in participants who have received RGX-111 (a gene therapy intended to deliver a functional copy of the alpha-L-iduronidase gene (IDUA) to the central nervous system) in a separate parent study.

Study Overview

• Status: Enrolling by invitation
• Conditions: Mucopolysaccharidosis I
• Intervention / Treatment: Genetic: No Intervention

Detailed Description

This is a prospective, multicenter, observational, follow-up study to evaluate the long-term safety and efficacy of RGX-111 after a single administration. Eligible participants are those who previously participated in a clinical study where they received a single IC or ICV administration of RGX-111. Enrollment of each participant in this study should occur on the same day or after the participant has completed the end of study (EOS) visit or early discontinuation visit (EDV) from a previous (parent) clinical study. Participants will be followed for up to five years after RGX-111 administration (inclusive of the parent study) or until RGX-111 is commercially available in the participant's country, whichever occurs first. No treatment will be directed under this observational protocol. The total study duration for each participant may vary depending on when s/he enrolls in the current study following RGX-111 administration in the parent study.

• Study Type: Observational
• Enrollment (Estimated): 8

Contacts and Locations

Study Locations

• Brazil
  • RS
    • Porto Alegre, RS, Brazil, 90035-903
      • Hospital de Clínicas de Porto Alegre
• United States
  • California
    • Orange, California, United States, 92868
      • Children's Hospital of Orange County
  • Pennsylvania
    • Philadelphia, Pennsylvania, United States, 19104
      • Children's Hospital of Philadelphia

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Child; Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Received RGX-111 in a separate parent trial.

Description

Inclusion Criteria:

• To be eligible, a participant must have previously received RGX-111 in a separate parent trial.
• Participant or participant's legal guardian(s) is/(are) willing and able to provide written, signed informed consent.

Exclusion Criteria:

• None.

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort	Intervention / Treatment
RGX-111 Recipients; Subjects who have received RGX-111 in a separate parent study.	Genetic: No Intervention; Observational study

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evaluation of the long-term safety of RGX-111	Incidences of treatment-emergent adverse events (TEAE) and serious adverse events (SAEs) over time	5 years inclusive of parent study

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Biomarkers	Change from baseline in Glycosaminoglycan levels (ng/mL)	5 years inclusive of parent study
Biomarkers	Change from baseline in measurement of biomarkers in cerebrospinal fluid (CSF).	5 years inclusive of parent study
Biomarkers	Change from baseline in measurement of biomarkers in plasma.	5 years inclusive of parent study
Biomarkers	Change from baseline in measurement of biomarkers in urine.	5 years inclusive of parent study
Change from baseline in neurodevelopmental parameters	as measured by the Bayley Scales of Infant and Toddler Development Third Edition (BSID-III). The BSID-III assesses children with developmental functioning ranging from 1-42 months. In this study, participants will be assessed for the Cognitive, Language, and Motor domains. The domains have different scoring ranges, with higher subtest raw scores indicating better function, but can be normalized for cross-domain comparison.	5 years inclusive of parent study
Change from baseline in neurodevelopmental parameters	Change in baseline adaptive behavior as measured by Vineland Adaptive Behavior Scales Third Edition (VABS-III). The VABS-III assesses adaptive behavior in individuals from infancy to age 90 years. In this study, 4 domains of Communication, Daily Living Skills, Socialization, and Motor Skills will be assessed. The domains have different scoring ranges, with higher subdomain raw scores indicating greater function, but can be normalized for cross-domain comparison.	5 years inclusive of parent study
Change from baseline in neurodevelopmental parameters	As measured by the Wechsler Abbreviated Scale of Intelligence (WASI-II). The WASI-II assesses intelligence for individuals from ages 6 to 90 years old. The assessment yields composite scores that estimates verbal comprehension and perceptual reasoning abilities. The subtests have different scoring ranges, with higher subtest raw scores indicating completion of more complex items, but can be normalized for cross-subtest comparison.	5 years inclusive of parent study
Change from baseline in neurodevelopmental parameters	As measured by the Wechsler Preschool and Primary Scale of Intelligence Fourth Edition (WPPSI-IV). The WPPSI-IV measures cognitive development in young children from ages 30-91 months of age. This study utilizes the General Ability Index (GAI) comprised of 4 core subtests depending on the child's age. The subtests have different scoring ranges, with higher subtest raw scores indicating completion of more complex items, but can be normalized for cross-subtest comparison.	5 years inclusive of parent study
Change from baseline in neurodevelopmental parameters	As measured by the Tests of Variables of Attention (TOVA)	5 years inclusive of parent study

Collaborators and Investigators

• Sponsor: REGENXBIO Inc.

Study record dates

Study Major Dates

• Study Start (Actual): July 24, 2023
• Primary Completion (Estimated): September 1, 2027
• Study Completion (Estimated): September 1, 2027

Study Registration Dates

• First Submitted: October 5, 2023
• First Submitted That Met QC Criteria: October 25, 2023
• First Posted (Actual): October 26, 2023

Study Record Updates

• Last Update Posted (Actual): October 26, 2023
• Last Update Submitted That Met QC Criteria: October 25, 2023
• Last Verified: October 1, 2023

More Information

Terms related to this study

• Keywords: gene therapy; MPS I; hurler syndrome
• Additional Relevant MeSH Terms: Metabolic Diseases; Genetic Diseases, Inborn; Connective Tissue Diseases; Carbohydrate Metabolism, Inborn Errors; Metabolism, Inborn Errors; Lysosomal Storage Diseases; Mucinoses; Mucopolysaccharidoses; Mucopolysaccharidosis I
• Other Study ID Numbers: RGX-111-5101

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No