Study of Intrathecal Administration of Onasemnogene Abeparvovec-xioi for Spinal Muscular Atrophy (STRONG)
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ClinicalTrials.gov Identifier: NCT03381729 |
Recruitment Status :
Terminated
(Based upon overall strategic objectives within the broader intrathecal clinical development program, Novartis Gene Therapies decided to terminate the study early.)
First Posted : December 22, 2017
Results First Posted : February 16, 2023
Last Update Posted : April 24, 2023
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Condition or disease | Intervention/treatment | Phase |
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Spinal Muscular Atrophy | Biological: Onasemnogene Abeparvovec-xioi | Phase 1 |

Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 32 participants |
Allocation: | Non-Randomized |
Intervention Model: | Parallel Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | Phase I, Open-Label, Dose Comparison Study of AVXS-101 for Sitting But Non-ambulatory Patients With Spinal Muscular Atrophy |
Actual Study Start Date : | December 14, 2017 |
Actual Primary Completion Date : | November 18, 2021 |
Actual Study Completion Date : | November 18, 2021 |

Arm | Intervention/treatment |
---|---|
Experimental: Dose A
Intrathecal administration 6.0 X 10^13 vg of onasemnogene abeparvovec-xioi
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Biological: Onasemnogene Abeparvovec-xioi
Self-complementary AAV9 carrying the SMN gene under the control of a hybrid CMV enhancer/chicken-β-actin promoter
Other Name: Zolgensma |
Experimental: Dose B
Intrathecal administration 1.2 X 10^14 vg of onasemnogene abeparvovec-xioi
|
Biological: Onasemnogene Abeparvovec-xioi
Self-complementary AAV9 carrying the SMN gene under the control of a hybrid CMV enhancer/chicken-β-actin promoter
Other Name: Zolgensma |
Experimental: Dose C
Intrathecal administration 2.4 X 10^14 vg of onasemnogene abeparvovec-xioi
|
Biological: Onasemnogene Abeparvovec-xioi
Self-complementary AAV9 carrying the SMN gene under the control of a hybrid CMV enhancer/chicken-β-actin promoter
Other Name: Zolgensma |
- Age 6 to <24 Months Only: Number of Participants Who Achieved the Ability to Stand Alone [ Time Frame: From Day 1 up to Month 12 ]Defined by the Bayley Scales of Infant and Toddler Development (BSID) Gross Motor (GM) subtest performance criteria number 40, confirmed by video recording, as a participant who stands alone for at least 3 seconds unsupported.
- Age 24 to <60 Months Only: Change From Baseline in Hammersmith Functional Motor Scale-Expanded (HFMSE) Score at Month 12 [ Time Frame: Baseline and Month 12 ]The HFMSE contained 33 items which were scored on a scale of 0-2 with a total achievable score ranging from 0, if all activities are failed, to 66, if all the activities are achieved. A positive change from baseline indicates a better outcome.
- Number of Participants Who Experienced a Treatment-emergent Adverse Event (TEAE) [ Time Frame: Adverse events were collected from the single dose of study treatment until the end of study visit (12 months for Cohort 1 and 2 and 15 months for Cohort 3) ]
A TEAE was defined as any event that began or worsened in severity on or after the administration of AVXS-101 through the last study visit.
Evaluation of TEAEs included the number of participants with at least one:
- TEAE
- Serious TEAE
- TEAE related to AVXS-101
- TEAE with Common Terminology Criteria for Adverse Events (CTCAE) grade ≥ 3 (grade 3 = severe or medically significant to grade 5 = death related to TEAE)
- Number of Participants Who Achieved the Ability to Walk Alone [ Time Frame: From Day 1 up to Month 12 ]Defined by the BSID GM subtest performance criteria number 43, confirmed by video recording, as a participant who takes 5 coordinated independent steps.
- Average Number of Hours Per Day of Non-invasive Ventilatory Support [ Time Frame: Months 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, and 12 ]Participants were assessed by a pulmonologist and may have been fitted with a non-invasive positive pressure ventilatory (e.g., Bilevel Positive Airway Pressure BiPAP) at the discretion of the pulmonologist and/or investigator. The number of hours per day of non-invasive ventilatory support was captured continuously by the device.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 6 Months to 60 Months (Child) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Key Inclusion Criteria
- Patients ≥6 months and up to 60 months (1800 days) of age at time of dosing following diagnostic confirmation during screening period by genotype who demonstrate the ability to sit unassisted for 10 or more seconds but cannot stand or walk
- Diagnostic confirmation by genotype includes lab documentation of homozygous absence of SMN1 exon 7; with exactly three copies of SMN2
- Negative gene testing for SMN2 gene modifier mutation (c.859G>C)
- Onset of clinical signs and symptoms consistent with spinal muscular atrophy (SMA) at < 12 months of age
- Able to sit independently and not standing or walking independently. Definition of sitting independently is defined by the World Health Organization Multicentre Growth Reference Study (WHO-MGRS) criteria of being able to sit up unsupported with head erect for at least 10 seconds. Child should not use arms or hands to balance body or support position (Wijnhoven 2004)
- Be up-to-date on childhood vaccines that include palivizumab prophylaxis (also known as Synagis) to prevent respiratory syncytial virus (RSV) infections are also recommended in accordance with American Academy of Pediatrics (AAP 2009)
Key Exclusion Criteria
- Current or historical ability to stand or walk independently
- Contraindications for spinal tap procedure or administration of intrathecal therapy or presence of an implanted shunt for the drainage of CSF or an implanted central venous (CNS) catheter
- Severe contractures as determined by designated Physical Therapist(s) at screening that interfere with either the ability to attain/demonstrate functional measures or interferes with ability to receive intrathecal (IT) dosing
- Severe scoliosis (defined as ≥ 50° curvature of spine) evident on X-ray examination
- Previous, planned or expected scoliosis repair surgery/procedure within 1 year of dose administration
- Use of invasive ventilatory support (tracheotomy with positive pressure) or pulse oximetry < 95% saturation at screening while the patient is awake, or for high altitudes > 1000 m, oxygen saturation < 92% while the patient is awake
- Pulse oximetry saturation must not decrease ≥ four (4) percentage points between screening and highest value on day of dosing
- Use or requirement of non-invasive ventilatory support for 12 or more hours daily over the two (2) weeks prior to dosing
- Medical necessity for a gastric feeding tube, where the majority of feedings are given by non-oral methods (i.e., nasogastric tube or nasojejunal tube) or patients whose weight-for-age falls below the 3rd percentile based on WHO Child Growth Standards (Onis 2006). Placement of a permanent gastrostomy prior to screening is not an exclusion
- Use or requirement of non-invasive ventilatory support for 12 or more hours daily over the two (2) weeks prior to dosing
- Medical necessity for a gastric feeding tube, where the majority of feedings are given by non-oral methods or patients whose weight-for-age falls below the 3rd percentile based on WHO Child Growth Standards (Onis 2006). Placement of a permanent gastrostomy prior to screening is not an exclusion
- Active viral infection (includes human immunodeficiency virus (HIV) or serology positive for hepatitis B or C, or Zika virus)
- Serious non-respiratory tract illness requiring systemic treatment and/or hospitalization within two (2) weeks prior to study entry
- Respiratory infection requiring medical attention, medical intervention or increase in supportive care of any manner within four (4) weeks prior to study entry
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Severe non-pulmonary/respiratory tract infection within four (4) weeks before study dosing or concomitant illness that in the opinion of the Principal Investigator (PI) creates unnecessary risks for gene transfer such as:
- Major renal or hepatic impairment
- Known seizure disorder
- Diabetes mellitus
- Idiopathic hypocalciuria
- Symptomatic cardiomyopathy
- History of bacterial meningitis or brain or spinal cord disease, including tumors, or abnormalities by magnetic resonance imaging (MRI) or computerized tomography (CT) that would interfere with the lumbar puncture (LP) procedures or CSF circulation
- Known allergy or hypersensitivity to prednisolone or other glucocorticosteroids or their excipients
- Known allergy or hypersensitivity to iodine or iodine-containing products
- Concomitant use of any of the following: drugs for treatment of myopathy or neuropathy, agents used to treat diabetes mellitus, or ongoing immunosuppressive therapy, plasmapheresis, immunomodulators such as adalimumab, or immunosuppressive therapy within 3 months of study dosing
- Inability to withhold use of laxatives or diuretics in the 24 hours prior to dose administration
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Anti-AAV9 antibody titers >1:50 as determined by Enzyme-linked Immunosorbent Assay (ELISA) binding immunoassay
- Should a potential patient demonstrate anti AAV9 antibody titer > 1:50, he or she may receive retesting within 30 days of the screening period and will be eligible to participate if the anti AAV9 antibody titer upon retesting is ≤ 1:50
- Clinically significant abnormal laboratory values (GGT, ALT, and AST, or total bilirubin > 2 × ULN, creatinine ≥ 1.0 mg/dL, hemoglobin [Hgb] < 8 or > 18 g/dL; white blood cell [WBC] > 20,000 per cmm) prior to gene replacement therapy. Patients with an elevated bilirubin level that is unequivocally the result of neonatal jaundice shall not be excluded
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Participation in recent SMA treatment clinical trial or receipt of an investigational or approved compound product or therapy received with the intent to treat SMA at any time prior to screening for this study
- Oral beta agonists must be discontinued 30 days prior to dosing.
- Inhaled albuterol specifically prescribed for the purposes of respiratory (bronchodilator) management is acceptable and not a contraindication at any time prior to screening for this study
- Expectation of major surgical procedures during the 1-year study assessment period

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03381729
United States, California | |
UCLA | |
Los Angeles, California, United States, 90095 | |
Stanford University | |
Stanford, California, United States, 94305 | |
United States, Florida | |
Nemours Children's Hospital | |
Orlando, Florida, United States, 32827 | |
United States, Illinois | |
Ann & Robert H. Lurie Children's Hospital | |
Chicago, Illinois, United States, 60611 | |
United States, Maryland | |
Johns Hopkins | |
Baltimore, Maryland, United States, 21287 | |
United States, Massachusetts | |
Boston Children's Hospital | |
Boston, Massachusetts, United States, 02115 | |
United States, Missouri | |
Washington University | |
Saint Louis, Missouri, United States, 63130 | |
United States, Ohio | |
Nationwide Children's Hospital | |
Columbus, Ohio, United States, 43205 | |
United States, Pennsylvania | |
Children's Hospital of Philadelphia | |
Philadelphia, Pennsylvania, United States, 19104 | |
United States, Texas | |
UT Southwestern | |
Dallas, Texas, United States, 75390 | |
United States, Utah | |
University of Utah | |
Salt Lake City, Utah, United States, 84112 |
Documents provided by Novartis ( Novartis Gene Therapies ):
Publications:
Responsible Party: | Novartis Gene Therapies |
ClinicalTrials.gov Identifier: | NCT03381729 |
Other Study ID Numbers: |
AVXS-101-CL-102 2020-003678-28 ( EudraCT Number ) COAV101A12102 ( Other Identifier: Novartis ) |
First Posted: | December 22, 2017 Key Record Dates |
Results First Posted: | February 16, 2023 |
Last Update Posted: | April 24, 2023 |
Last Verified: | April 2023 |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Gene Transfer Gene Therapy Adeno-associated virus |
Survival Motor Neuron SMN AAV9 |
Muscular Atrophy Muscular Atrophy, Spinal Atrophy Pathological Conditions, Anatomical Neuromuscular Manifestations Neurologic Manifestations |
Nervous System Diseases Spinal Cord Diseases Central Nervous System Diseases Motor Neuron Disease Neurodegenerative Diseases Neuromuscular Diseases |