NCT07287982 · argenx
A Study to Assess the Safety, Tolerability, Efficacy, Pharmacokinetics, and Immunogenicity of Intravenous Administration of ARGX-119 in Pediatric Participants Aged 5 to Less Than 18 Years With Spinal Muscular Atrophy
(Sparkle)
What this study is about
This study aims to find the correct dose of ARGX-119 for children with SMA. The study will also look at how safe the study drug is, how well it works, how it moves through the body, and how the immune system responds to it.
View original scientific description
This study aims to find the correct dose of ARGX-119 for children with SMA. The study will also look at how safe the study drug is, how well it works, how it moves through the body, and how the immune system responds to it. The study consists of a double-blinded treatment period (DBTP) where participants will either receive ARGX-119 IV or placebo IV, in addition to disease-modifying therapy (DMT) for 24 weeks. Participants who complete the DBTP will enter the open-label active-treatment extension period (ATEP) during which all participants will receive ARGX-119 IV up to 100 weeks (approximately 2 years).
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Is aged ≥5 to \<18 years when completing the informed consent process, defined as providing informed assent according to local regulations and having a parent or guardian sign the ICF, and can comply with protocol
- requirements.
- Has documented historical genetic diagnosis of 5q-SMA.
- Currently receiving a stable SMA treatment regimen (nusinersen or risdiplam) and/or have a history of onasemnogene abeparvovec treatment
- Must be able to walk at least 50 meters without walking aids in the 6MWT at screening
Exclusion criteria
- Known medical condition that would interfere with an accurate assessment of SMA, confound the results of the study, or put the participant at undue risk, as assessed by the investigator
- Recent major surgery, except spinal fusion, within 3 months of screening or intends to have major surgery during the study
- Current or previous administration of antimyostatin therapies in the past 6 months
- Severe scoliosis (defined as curvature \>40°) and/or contractures at screening. o History of spinal fusion within 6 months before screening or planned during the study
- Respiratory insufficiency, defined by the medical necessity for invasive or noninvasive ventilation for daytime treatment while awake. Ventilation used overnight or during daytime naps is acceptable.
Where
- Little Rock, Arkansas
- San Diego, California
- Stanford, California
- Hartford, Connecticut
- Kissimmee, Florida
- Chicago, Illinois
- Iowa City, Iowa
- Baltimore, Maryland
- Boston, Massachusetts
- Columbia, Missouri
- New York, New York
- Hillsborough, North Carolina
And 5 more locations — see the full list below.
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced May 22, 2026 · Source of record for eligibility and locations