Long-term Follow-Up for RGX-121

Mucopolysaccharidosis II Clinical Trial

Official title:

A Long-term Follow-up Study to Evaluate the Safety and Efficacy of RGX-121

Clinical Trial Details — Status: Enrolling by invitation

Administrative data

• NCT number: NCT04597385
• Other study ID #: RGX-121-5101
• Status: Enrolling by invitation
• Start date: March 14, 2021
• Est. completion date: September 2025

Study information

• Verified date: August 2021
• Source: Regenxbio Inc.
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

RGX-121-5101 is the long-term follow-up study to the RGX-121-101 first in human study where participants received RGX-121, a gene therapy intended to deliver a functional copy of the iduronate-2-sulfatase gene (IDS) to the central nervous system. This study will evaluate the long-term safety and efficacy of RGX-121.

Description:

This is a prospective follow-up study to evaluate the long-term safety and efficacy after a single administration of RGX-121. Eligible participants are those who previously have enrolled in clinical study RGX-121-101 and received a single intracisternal (IC) or intracerebroventricular (ICV) infusion of RGX-121. Enrollment of each participant will occur the same day or after the participant has completed the end of study (EOS) visit or early termination visit (ET) from the previous (parent) study. Participants will be followed in this study cumulatively for up to 5 years after RGX-121 administration (inclusive of the parent study) or until RGX-121 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 they enroll in the current study following RGX-121 administration in the parent study.

Recruitment information / eligibility

• Status: Enrolling by invitation
• Enrollment: 12
• Est. completion date: September 2025
• Est. primary completion date: September 2025
• Accepts healthy volunteers: No
• Gender: Male
• Age group: 28 Months and older

Eligibility

Inclusion Criteria:

• To be eligible, a participant must have previously received RGX-121 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:

• Patient has not received RGX-121 previously in a separate parent trial.

Related Conditions & MeSH terms

• Mucopolysaccharidoses
• Mucopolysaccharidosis II

Intervention

Other:
• Long-term Follow-Up
No intervention

Locations

Country	Name	City	State
United States	Children's Hospital of Pittsburgh - UPMC: Program for Neurodevelopment in Rare Disorders	Pittsburgh	Pennsylvania

Sponsors (1)

Lead Sponsor	Collaborator
Regenxbio Inc.

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Incidences of Adverse Events over time.	Safety	3 years
Primary	Incidences of Serious Adverse Events over time	Safety	3 year
Secondary	Biomarkers [Time frame: 1 Month, 12 Months, 24 Months, 36 Months]	Change from baseline in Glycosaminoglycan levels (ng/mL)	3 years
Secondary	Changes in neurodevelopmental parameters of cognitive function [Time Frame: 1 Month, 12 Months, 24 Months, 36 Months]	Change from baseline in neurodevelopment parameters of cognitive, behavioral and adaptive function as measured by the Bayley Scales of Infant and Toddler Development, 3rd Edition (BSID-III) or Kaufman Assessment Battery for Children, 2nd Edition (KABC-II).	3 years
Secondary	Changes in neurodevelopmental parameters of cognitive function [Time Frame: 1 Month, 12 Months, 24 Months, 36 Months]	Change from baseline in neurodevelopment parameters of cognitive, behavioral and adaptive function as measured by the Mullen Scales of Early Learning (MSEL)	3 years
Secondary	Changes in neurodevelopmental parameters of adaptive behavior function [Time Frame: 1 Month, 12 Months, 24 Months, 36 Months]	Vineland Adaptive Behavior Scales Second Edition (VABS-II)	3 years