MedPath

Safety and Efficacy of GS-100 Gene Therapy in Patients With NGLY1 Deficiency

Phase 1
Recruiting
Conditions
NGLY1 Deficiency
Interventions
Genetic: GS-100
Registration Number
NCT06199531
Lead Sponsor
Grace Science, LLC
Brief Summary

A non-randomized, open-label, dose escalation study of a single intracerebroventricular (ICV) administration of a gene replacement therapy in subjects who are 2 to 18 years old with NGLY1 Deficiency.

Detailed Description

This study is a first in human (FIH) open-label, dose escalation study designed to assess the safety and efficacy of administration of an adeno-associated viral vector serotype 9 (AAV9) carrying the gene encoding N-glycanase 1 (NGLY1) in subjects with NGLY1 Deficiency. The study treatment will be delivered via intracerebroventricular (ICV) injection. All outcomes (primary, secondary, exploratory) will be assessed at 52 weeks. Safety will be monitored continuously throughout the study for adverse / serious adverse events and dose limiting toxicities. Efficacy outcomes will be assessed at baseline and 52 weeks. The co-primary outcomes will be change from baseline in cerebrospinal fluid (CSF) GlcNAc-Asn (GNA, or N-acetylglucosamine), the NGLY1 Deficiency biomarker, and change in motor subdomain on the Bayley Scales of Infant and Toddler Development (BSID-4). Secondary outcomes will include weight (Z-score), clinical and caregiver impressions of change, and other neurocognitive assessment tools. Exploratory outcomes will include brain volumes as measured by magnetic resonance imaging (MRI), quality of life assessments (including sleep habits), liver function test results, and lacrimation assessments. Each participant will be followed for safety and efficacy for 5 years after treatment.

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
6
Inclusion Criteria
  • Patients must be 2 to 18 years of age, inclusive, at the time of signing the informed consent form (ICF)

  • Patients with a documented diagnosis of NGLY1 Deficiency based on detection of biallelic variants in the NGLY1 gene via molecular genetic sequencing

  • Elevated GNA levels may be considered alongside genetic sequencing data and other clinical data to assist with diagnosis confirmation

  • Patients with two or more of the following clinical features typical of NGLY1 Deficiency:

    1. Global developmental delay and/or intellectual disability
    2. Hyperkinetic movement disorder
    3. Transient elevation of transaminases
    4. (Hypo)alacrima
    5. Peripheral neuropathy
  • For patients with epilepsy who require anti-seizure medications for seizure control: must be on a stable regimen for 28 days prior to enrollment

  • Patients willing and capable per investigator opinion to comply with study procedures and requirements

  • Females of childbearing potential must have a negative serum pregnancy test at screening and must agree to use an acceptable method of highly effective contraception from screening through the end of the study

  • Patients or parent(s)/guardian(s) must be willing and able to provide written consent after the nature of the study has been explained and prior to performance of any research-related procedures

Exclusion Criteria
  • Patients at Level 5 of both the Gross Motor Function Classification System Expanded and Revised (GMFCS E&R) and the Communication Function Classification System (CFCS) scales as assessed by the investigator

  • Contraindication to use of corticosteroids or history of a condition that could worsen with corticosteroid therapy, as assessed, and determined by the investigator

  • Signs / symptoms of increased intracranial pressure (ICP), history of space occupying lesion, or ventricular shunt that would preclude ICV procedures or safety assessments

    a. If clinical signs or symptoms of increased ICP are present (such as headache, vomiting, altered mental status), an ophthalmology examination will be performed to assess for papilledema and/or venous pulsations

  • Any comorbid medical or behavioral condition that, in the opinion of the investigator, may adversely affect the safety and well-being of the participant during the study, interfere with completion of the study procedures or follow-up, or compound interpretation of the study results

  • Vital signs outside age-based normative values:

    1. Blood pressure: values > 99th percentile as cited in the National Heart, Lung and Blood Institute (NHLBI) guidelines for blood pressure levels based on subject's age, height and sex (nhlbi.nih.gov/files/docs/guidelines/child_tbl.pdf)
    2. Temperature: evidence of fever such as body temperature (e.g., orally measured) of 38.0°C (100.3°F)
    3. Respiratory rate in breaths per minute: toddler (1-3 years old): 24-40; preschooler (4-5 years old): 22-34 breaths per minute; school-aged child (6-12 years old): 18-30 breaths per minute; adolescence (13-18 years old): 12-16.
    4. Oxygen saturation on room air < 92%
  • Any condition that in the opinion of the investigator or the study medical monitor would prevent the patient from fully complying with the requirements of the study (including the corticosteroid treatment outline in the protocol) and/or would impact or interfere with the evaluation and interpretation of patient safety or efficacy results

  • Known allergy or hypersensitivity to the GS-100 investigational product formulation

  • Prior treatment with gene therapy

  • Treatment with any investigational product (IP) within 30 days or 5 half-lives of the IP, whichever is longer, prior to screening period. For patients who have received a prior investigational product, all ongoing AEs experienced while receiving the investigational product must have been resolved prior to screening for this study

  • Concurrent enrollment in another clinical study, unless it is an observational (non-interventional) clinical study that does not interfere with the requirements of the current protocol and does not have the potential to impact the evaluation of safety and efficacy of GS-100

  • Coagulation dysfunction at screening as defined by the following:

    a. INR: ≥1.4 x Upper Limit of Normal (ULN)

  • Any current infection with hepatitis B virus (HBV) as evidenced by as evidenced by positive HBV surface antigen (HBsAg), and/or HBV core antibody (HBcAb) at screening. Isolated HBsAb positivity for HBV vaccination in conjunction with negative confirmatory HBV DNA testing at screening is not exclusionary

  • Any prior or current infection with hepatitis C virus (HCV) as evidenced by positive HCV antibody testing and confirmed by positive polymerase chain reaction (PCR) RNA testing at screening

  • Any of the following abnormal laboratory values:

    1. Hemoglobin level: < 9 g/dL
    2. Absolute neutrophil count: < 1000 cells/microliter
    3. Platelet count: < 100,000/mm3
    4. Creatinine: > 1.25 x ULN
  • Have a major surgery planned during the screening period through 52 weeks following GS-100 infusion, including major dental procedures (e.g., wisdom tooth extraction)

  • Pregnant or breastfeeding female patient

  • Patients that demonstrate elevated serum adrenocorticotropic hormone (ACTH) 1.5 times the upper limit of normal for the reference range must be referred for consultation with a pediatric endocrinologist to rule out primary adrenal insufficiency prior to being enrolled into the study. Patients may re-screen for participation in the study after medical consultation and / or possible treatment has been initiated to address any adrenal insufficiency

Study & Design

Study Type
INTERVENTIONAL
Study Design
SEQUENTIAL
Arm && Interventions
GroupInterventionDescription
Cohort 3bGS-1002-5 years old (High dose GS-100)
Cohort 2aGS-10013-18 years old, then 6-12 years old (Mid dose GS-100)
Cohort 2bGS-1002-5 years old (Mid dose GS-100)
Cohort 1bGS-1002-5 years old (Low dose GS-100)
Cohort 1aGS-10013-18 years old, then 6-12 years old (Low dose GS-100)
Cohort 3aGS-10013-18 years old, then 6-12 years old (High dose GS-100)
Primary Outcome Measures
NameTimeMethod
Coagulation as measured by prothrombin time (PT)5 years (multiple visits)
Alkaline phosphatase (ALP)5 years (multiple visits)
Chloride (meq/L)5 years (multiple visits)
Bicarbonate (meq/L)5 years (multiple visits)
Change in liver size by palpation5 years (multiple visits)
Complete blood count (CBC)5 years (multiple visits)
Partial prothrombin time (aPTT)5 years (multiple visits)
To assess for inflammation or evidence of microgliosis or astrocytosis on MRI5 years (multiple visits)
Change in cardiac size as assessed by chamber size and wall thickness on echocardiogram5 years (multiple visits)
Creatinine (mg/dL)5 years (multiple visits)
Albumin (g/dL)5 years (multiple visits)
Total bilirubin (mg/dL)5 years (multiple visits)
Alkaline phosphatase (U/L)5 years (multiple visits)
Incidence of adverse events (AEs) and serious AEs (SAEs)5 years (multiple visits)
International normalized ratio (INR)5 years (multiple visits)
Alanine aminotransferase (ALT)5 years (multiple visits)
Potassium (meq/L)5 years (multiple visits)
Direct bilirubin (mg/dL)5 years (multiple visits)
Calcium (mg/dL)5 years (multiple visits)
Phosphate (mg/dL)5 years (multiple visits)
Gamma-glutamyl transferase (GGT)5 years (multiple visits)
Serum troponins5 years (multiple visits)
Change in nerve conduction velocity (NCV) as assessed by nerve conduction studies5 years (multiple visits)
Change in cardiac function as assessed by ejection fraction on echocardiogram5 years (multiple visits)
Blood urea nitrogen (BUN) (mg/dL)5 years (multiple visits)
Glucose (mg/dL)5 years (multiple visits)
Total protein (g/dL)5 years (multiple visits)
Lactic dehydrogenase (U/L)5 years (multiple visits)
Sodium (meq/L)5 years (multiple visits)
Secondary Outcome Measures
NameTimeMethod
Change from baseline at 52 weeks in Clinical Global Impression of Change (CGI-C)52 weeks

Range from 1-7, with 1 being marked improvement

Detection of antibodies against AAV9 capsid (AAV9 Total antibodies, AAV9 Neutralizing antibodies) and NGLY1 (NGLY1 Total antibodies)5 years (multiple visits)
Change from baseline at 52 weeks in sitting/standing assessment at 52 weeks52 weeks
Change from baseline at 52 weeks in Wechsler Preschool and Primary Scale of Intelligence, Fourth Edition (WPPSI-IV)52 weeks

Standard scores are based on a mean of 100 and a standard deviation of 15; a higher score reflects a higher level of skill

Change from baseline at 52 weeks in Caregiver Global Impression of Severity (CaGI-S)52 weeks

Range from 1-7, with 1 being normal/no impairment

Change from baseline at 52 weeks in peripheral nerve function measured by nerve conduction velocity (NCV) in msecs52 weeks
Change from baseline at 52 weeks in Vineland Adaptive Behavior Scales-3 assessment (Vineland-3) for the Communication, Daily Living skills, Socialization, and Motor domains52 weeks

Standard scores for domains are based on a mean of 100 and a standard deviation of 15; a higher score reflects a higher level of skill

Change from baseline of GNA (GlcNAc-Asn, or N-acetylglucosamine) level in CSF5 years (multiple visits)
Assessment of NGLY1 and capsid-specific cellular immunity by enzyme-linked immunosorbent spot (ELISpot) on peripheral blood mononuclear cells (PBMC)5 years (multiple visits)
Change from baseline at 52 weeks in weight (Z-score)52 weeks
Change from baseline at 52 weeks in Pediatric Quality of Life Inventory (PedsQL)52 weeks

Total score 0-100; a higher score reflects a higher quality of life

Change from baseline at 52 weeks in Clinical Global Impression of Severity (CGI-S)52 weeks

Range from 1-7, with 1 being normal/no impairment

Change from baseline at 52 weeks in Bayley Scales of Infant and Toddler Development 4th Ed (BSID-4) for the Cognitive, Language, and Motor scales52 weeks

Total Raw Scores, Growth Score Values (GSVs), and Age Equivalent Scores will be analyzed; Raw Scores range 0-162; GSVs range 428-559; Age Equivalent Scores range 1-42 months; a higher score reflects a higher level of skill.

Change from baseline at 52 weeks in Gross Motor Function Measure (GMFM)52 weeks

Scores range from 0-264; a higher score reflects a higher level of skill.

Change from baseline at 52 weeks in seizure frequency in subjects with seizures52 weeks

Trial Locations

Locations (3)

Oakland Children's Hospital (UCSF Benioff)

🇺🇸

Oakland, California, United States

Columbia University Irving Medical Center

🇺🇸

New York, New York, United States

Texas Children's Hospital (Baylor College of Medicine)

🇺🇸

Houston, Texas, United States

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