CAMPSIITE™ RGX-121 Gene Therapy in Subjects With MPS II (Hunter Syndrome)
Mucopolysaccharidosis Type II (MPS II)
About this trial
This is an interventional treatment trial for Mucopolysaccharidosis Type II (MPS II) focused on measuring MPS II, gene therapy, Hunter Syndrome, Lysosomal Storage Disorder
Eligibility Criteria
Part 1 Inclusion Criteria:
- The subject's legal guardian(s) is (are) willing and able to provide written, signed informed consent after the nature of the study has been explained, and prior to any research-related procedures
- Is a male ≥4 months to < 5 years of age on Day 1
Must meet any of the following criteria:
- Has a documented diagnosis of MPS II and a has a neurocognitive testing score ≤ 77 (Bayley or Kaufman), OR
- Has a documented diagnosis of MPS II AND has a decline of ≥ 1 standard deviation on serial neurocognitive testing administered between 3 to 36 months apart (Bayley or Kaufman) OR
- Has a relative clinically diagnosed with severe MPS II who has the same IDS mutation as the subject AND in the opinion of a geneticist has inherited a severe form of MPS II OR
- Has documented mutation (s) in IDS that in the opinion of a geneticist is always known to result in a neuronopathic phenotype AND in the opinion of a clinician has a severe form of MPS II
Part 2 Inclusion Criteria:
- The subject's legal guardian(s) is (are) willing and able to provide written, signed informed consent after the nature of the study has been explained, and prior to any research-related procedures
- Is a male ≥4 months to < 5 years of age on Day 1
Has a documented diagnosis of neuronopathic MPS II. Neuronopathic MPS II can be documented with any of the following methods:
- Has a BSID-III Cognitive Composite score at or below -1 SD (85) from normative mean
- Has two consecutive neurodevelopmental assessments that support a decline on MSEL visual receptive, expressive language, or fine motor, or BSID-III cognition, expressive language, or fine motor ≥ 1 SD on serial neurocognitive testing administered between 3 to 36 months apart
- Has a relative clinically diagnosed with neuronopathic MPS II who has the same IDS mutation as the subject AND the subject, in the opinion of a geneticist, has inherited a neuronopathic form of MPS II
- Has documented mutation(s) in IDS known to result in a neuronopathic phenotype
Part 1 Exclusion Criteria:
- Has contraindications for intracisternal (IC) injection, intracerebroventricular (ICV) injection or lumbar puncture
- Has contraindications for immunosuppressive therapy
- Has neurocognitive deficit not attributable to MPS II or diagnosis of a neuropsychiatric condition
- Has a (cerebral) ventricular shunt that may impact the proper dosing of the subject
- Received hematopoietic stem cell transplantation
- Has had prior treatment with an AAV-based gene therapy product
- Received ELAPRASE® via intrathecal (IT) administration within 4 months of signing the ICF or experienced a serious hypersensitivity reaction to ELAPRASE®
- Has received any investigational product within 30 days of Day 1 or 5 half-lives before signing the ICF, whichever is longer
Part 2 Exclusion Criteria:
- Has a contraindication for an IC injection, ICV injection or lumbar puncture
- Has contraindications for immunosuppressive therapy
- Has neurocognitive deficit not attributable to MPS II or diagnosis of a neuropsychiatric condition
- Has a (cerebral) ventricular shunt that may impact the proper dosing of the subject
- Received hematopoietic stem cell transplantation
- Has had prior treatment with an AAV-based gene therapy product
- Is receiving idursulfase (ELAPRASE®) via intrathecal (IT) administration, or a blood brain barrier-crossing enzyme replacement therapy. Subjects receiving IT ELAPRASE® or a blood brain barrier-crossing ERT may enroll if they agree to discontinue these therapies starting at least 3 months prior to dosing with RGX-121, and for the 24 months of follow-up
- Has received any investigational product within 30 days of Day 1 or 5 half-lives before signing the ICF, whichever is longer
Sites / Locations
- University of California San Francisco, Benioff Children's HospitalRecruiting
- St. Peter's University HospitalRecruiting
- University of North Carolina Chapel Hill
- Children's Hospital of PhiladelphiaRecruiting
- Children's Hospital of Pittsburgh - UPMC: Program for Neurodevelopment in Rare Disorders
- Hospital de Clinicas de Porto AlegreRecruiting
Arms of the Study
Arm 1
Arm 2
Arm 3
Arm 4
Arm 5
Arm 6
Experimental
Experimental
Experimental
Experimental
Experimental
Experimental
Part 1: RGX-121 Dose 1
Part 1: RGX-121 Dose 2
Part 1: RGX-121 Dose 2 Expanded Cohort
Part 1: RGX-121 Dose 3
Part 1: RGX-121 Dose 3 Expanded Cohort
Part 2: RGX-121 Pivotal Expansion
1.3x10^10 GC/g brain mass of RGX-121
6.5x10^10 GC/g brain mass of RGX-121
6.5x10^10 GC/g brain mass of RGX-121
2.0x10^11 GC/g brain mass of RGX-121
2.9x10^11 GC/g brain mass of RGX-121 (transgene-specific PCR assay) equivalent to, 2.0x10^11 GC/g brain mass of RGX-121 (Poly-A-specific PCR assay)
2.9x10^11 GC/g brain mass of RGX-121 (transgene-specific PCR assay)