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Also known as RGX-121-3102
RGX-121 · 3 trials · 3 indications
To evaluate the effect of RGX-121 on the neurodevelopmental function as measured by the Bayley Scales of Infant and Toddler Development, 3rd Edition (BSID-III).
To evaluate the effect of RGX-121 on the neurodevelopmental function as measured by the Kaufman Assessment for Children, 2nd edition (KABC-II). The KABC-II is only given if the participant achieved the max ceiling on the BSID-III Cognitive scale at two consecutive administrations.
To evaluate the safety of RGX-121 for up to five years including serious and adverse events as assessed by Common Terminology Criteria for Adverse Events (CTCAE) (Version 5.0)
Number of participants with treatment-related adverse events and serious adverse events as assessed by CTCAE (Version 4.03).
CSF GAG levels (as measured by D2S6)
Neurodevelopmental function as measured by the Bayley Scales of Infant and Toddler Development, 3rd Edition (BSID-III) or Mullen Scales of Early Learning (MSEL). The Bayley Scales of Infant Development, or the BSID-III is an individually administered test, designed to evaluate the developmental functioning of infants and small children, between 1 and 42 months of age. The purpose of the test is to identify infants and children with developmental delay. The Mullen Scales of Early Learning (MSEL) is a developmental test to measure cognitive ability, language and motor development. The test has five scales: gross motor, visual reception, fine motor, receptive language, and expressive language. An increase in raw and age equivalent scores indicates neurodevelopmental skill acquisition. Standard scores compare function to age matched normative data.
Number of participants with treatment-related adverse events and serious adverse events as assessed by CTCAE (Version 5.0)
| Arm | Type | Description |
|---|---|---|
| 2.9×1011 GC/g brain mass of RGX 121 | EXPERIMENTAL | AAV9.CB7.hIDS |
| Part 1: RGX-121 Dose 1 | EXPERIMENTAL | 1.3x10\^10 GC/g brain mass of RGX-121 |
| Part 1: RGX-121 Dose 2 | EXPERIMENTAL | 6.5x10\^10 GC/g brain mass of RGX-121 |
| Part 1: RGX-121 Dose 2 Expanded Cohort | EXPERIMENTAL | 6.5x10\^10 GC/g brain mass of RGX-121 |
| Part 1: RGX-121 Dose 3 | EXPERIMENTAL | 2.0x10\^11 GC/g brain mass of RGX-121 |
| Part 1: RGX-121 Dose 3 Expanded Cohort | EXPERIMENTAL | 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) |
| Part 2: RGX-121 Pivotal Expansion | EXPERIMENTAL | 2.9x10\^11 GC/g brain mass of RGX-121 (transgene-specific PCR assay) |
| Single Arm | EXPERIMENTAL | 6.5 × 10\^10 GC/g brain mass of RGX-121 |
| Name | Type | Description |
|---|---|---|
| RGX-121-3102 | GENETIC | Recombinant adeno-associated virus serotype 9 \[AAV9\] capsid containing human iduronate-2-sulfatase (hIDS) expression cassette |
| RGX-121 | GENETIC | Recombinant adeno-associated virus serotype 9 capsid containing human iduronate-2-sulfatase expression cassette |
Inclusion Criteria: * The participant'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 study-related procedures being performed. * Is a male ≥ 4 months to \< 5 years of age on Day 1. * Has a ...
RGX-121 is an investigational gene therapy developed by REGENXBIO Inc. for Mucopolysaccharidosis Type II, also known as MPS II or Hunter Syndrome. It is designed as a one-time treatment for this rare, X-linked disease that primarily affects males, and it is currently under review with the FDA.
RGX-121 is being developed to treat Mucopolysaccharidosis Type II, also called MPS II or Hunter Syndrome, a rare inherited disorder. The clinical program enrolls male participants, with trial eligibility starting as young as 4 months of age. It is not yet approved for commercial use.
RGX-121 targets IDS, the gene encoding iduronate-2-sulfatase. MPS II results from deficient IDS enzyme activity, and the gene therapy is designed to deliver a functional copy of the IDS gene so patients can produce the enzyme themselves. REGENXBIO Inc. (ticker RGNX) is the developer.
RGX-121 is developed by REGENXBIO Inc., which trades on Nasdaq under the ticker RGNX. The company sponsors the clinical program for MPS II, including the Phase 1, Phase 2 and Phase 3 studies, and holds the FDA designations granted for the asset.
RGX-121 is at the NDA/BLA stage, meaning REGENXBIO Inc. has advanced the gene therapy toward regulatory submission for MPS II. It has completed a Phase 1 trial and conducted Phase 2 and Phase 3 studies. It is investigational and has not been approved by the FDA.
The RGX-121 program includes NCT04571970, a completed Phase 1 trial in children 5 years and older; NCT03566043, the active Phase 2 CAMPSIITE study with 48 participants in the United States and Brazil; and NCT07236606, an active Phase 3 trial in the United States. Total enrollment across the program is 54.
RGX-121-3102 is an alternative designation used for RGX-121, the gene therapy from REGENXBIO Inc. for MPS II. The name RGX-121-3102 appears in the Phase 3 trial NCT07236606, which is evaluating the therapy in participants with MPS II, also known as Hunter Syndrome.