Spinal Muscular Atrophy (SMA)Phase 2SparkleNCT07287982
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
A Phase 2 study testing ARGX-119 IV in people with Spinal Muscular Atrophy (SMA), run by argenx at 28 sites in 4 countries.
Trial summary
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. Read more about this study
- Who is it for?
- Ages 5 to 17 years
- Conditions the study is for
- Spinal Muscular Atrophy (SMA)
- What is being tested?
- ARGX-119 IV
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 60 participants
- Where
- 28 sitesin 4 countries
- Study dates
- 19 Dec 2025to 28 May 2029
- Phase
- Phase 2
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 5 to 17 years
- All sexes
- No healthy volunteers
- Child
Who may be able to join
- 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
Who cannot join
- 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.
Trial locations and contacts
28 sites in 4 countries. Contact the study team or a site near you to ask about taking part.
28 sites in 4 countries
United States16 sites, 15 recruiting
- Not yet recruiting
The Johns Hopkins Hospital
Baltimore, Maryland, 21205
Jessica Nance, (410) 955-4259, jnance6@jhmi.edu
Jessica Nance, Dr.
- Recruiting
Boston Children's Hospital
Boston, Massachusetts, 02115
Samantha Remis, (617) 355-2752, samantha.remis@childrens.harvard.edu
Basil Darras, Dr.
- Recruiting
Ann & Robert H. Lurie Children's Hospital of Chicago
Chicago, Illinois, 60611
Alka Maheshwari, (815) 444-6362, amaheshwari@luriechildrens.org
Nancy Kuntz, Dr.
- Not yet recruiting
The Curators of the University of Missouri on behalf of University of Missouri Health Care
Columbia, Missouri, 65212
Heather McHatton, (573) 882-7619, heathermchatton@health.missouri.edu
Jane Emerson, Dr.
- Recruiting
Neurology Rare Disease Center
Flower Mound, Texas, 75028
Natalie Gomez, (972) 999-1011, Natalie.Gomez@Neuromdcenter.com
Diana Castro, Dr.
- Recruiting
Connecticut Children's Medical Center
Hartford, Connecticut, 06106
Gyula Acsadi, (860) 545-9460, gacsadi@connecticutchildrens.org
Gyula Acsadi, Dr.
- Recruiting
Rare Disease Research NC, LLC
Hillsborough, North Carolina, 27278
Norma Davis, (470) 665-3051, norma.davis@rarediseaseresearch.com
Edward Smith, Dr.
- Recruiting
Texas Children's Hospital
Houston, Texas, 77030
Timothy Lotze, (832) 822-1779, tlotze@bcm.edu
Timothy Lotze, Dr.
- Recruiting
University of Iowa Stead Family Children's Hospital
Iowa City, Iowa, 52242
Katherine Mathews, (319) 356-1851, katherine-mathews@uiowa.edu
Katherine Mathews, Dr.
- Recruiting
Rare Disease Research FL LLC
Kissimmee, Florida, 34746
Maria Cordero, (407) 545-7610, maria.cordero@rarediseaseresearch.com
Renata Shih, Dr.
- Recruiting
Arkansas Children's Hospital
Little Rock, Arkansas, 72202
Steven Giompoletti, (501) 364-1430, giompolettis@archildrens.org
Kapil Arya, Dr.
- Recruiting
Columbia University Herbert Irving Comprehensive Cancer Center
New York, New York, 10032
Claudia Chiriboga, (646) 426-3876, cac3@cumc.columbia.edu
Claudia Chiriboga, Dr.
- Not yet recruiting
Childrens Hospital of The Kings Daughters
Norfolk, Virginia, 23507
Crystal Proud, (757) 668-9920, crystal.proud@chkd.org
Crystal Proud, Dr.
- Not yet recruiting
Children's Hospital Philadelphia - Neurology
Philadelphia, Pennsylvania, 19104
Karen Monono, (267) 425-0158, mononok@chop.edu
John Brandsema, Dr.
- Withdrawn
Rady Childrens Hospital
San Diego, California, 92123
- Recruiting
Stanford University Medical Center
Stanford, California, 94305
Lidia Choniawko, (650) 304-8094, lidiacho@stanford.edu
Carolina Tesi Rocha, Dr.
United Kingdom7 sites, 7 recruiting
- Recruiting
Birmingham Heartlands Hospital
Birmingham, West Midlands, B9 5SS
Deepak Parasuraman, +441384456111, deepak.parasuraman@uhb.nhs.uk
Deepak Parasuraman
- Recruiting
Addenbrooke's Hospital
Cambridge, Cambridgeshire, CB2 0QQ
Deepa Krishnakumar, +4412232451514, deepa.krishnakumar@nhs.net
Deepa Krishnakumar
- Recruiting
Royal Hospital for Children
Glasgow, Strathclyde, G51 4TF
Shuko Joseph, +441414516527, shuko.joseph2@nhs.scot
Shuko Joseph
- Recruiting
Leeds General Infirmary
Leeds, West Yorkshire, LS1 3EX
Anne-Marie Childs, +441133923113, anne-marie.childs@nhs.net
Anne-Marie Childs
- Recruiting
Great Ormond Street Hospital for Children
London, Greater London, WC1N 3JH
Mariacristina Scoto, +442079052639, mariacristina.scoto@gosh.nhs.uk
Mariacristina Scoto
- Not yet recruiting
MDUK Oxford Neuromuscular Centre
Oxford, Oxfordshire, OX3 9DU
Laurent Servais, +441865741166, laurent.servais@paediatrics.ox.ac.uk
Laurent Servais
- Recruiting
Sheffield Children's Hospital
Sheffield, South Yorkshire, S10 2TH
Min Ong, +441142717000, min.ong@nhs.net
Min Ong
Canada3 sites, 3 recruiting
- Not yet recruiting
University of Calgary - Alberta Children's Hospital
Calgary, Alberta, T3B 6A*
Jean Mah, 4039557816, jean.mah@albertahealthservices.ca
Jean Mah
- Not yet recruiting
The Hospital for Sick Children
Toronto, Ontario, M5G 1X8
Hernan Gonorazky, 4168131500, hernan.gonorazky@sickkids.ca
Hernan Gonorazky
- Not yet recruiting
BC Children's Hospital
Vancouver, British Columbia, V6H 3V4
Kathryn Selby, 60487523452121, kselby@cw.bc.ca
Kathryn Selby
Australia2 sites, 2 recruiting
- Not yet recruiting
Royal Children's Hospital
Parkville, Victoria, 3052
Eppie Yiu, +61412599077, eppie.yiu@rch.org.au
Eppie Yiu
- Recruiting
Sydney Children's Hospital, Randwick
Randwick, New South Wales, 2031
Michelle Farrar, 61293821549, michelle.farrar@health.nsw.gov.au
Michelle Farrar
About this study
Official title: A Phase 2 Double-Blinded, Randomized, Placebo-Controlled 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
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).
Read the detailed description
This phase 2 study aims to establish proof of concept with the age-appropriate dose of ARGX-119 in ambulant pediatric patients with spinal muscular atrophy (SMA). Despite available treatments, there remains an unmet medical need for patients with SMA. Neuromuscular junction (NMJ) dysfunction contributes to the pathophysiology of SMA, including muscle weakness and fatigability. Activation of muscle-specific kinase (MuSK) by ARGX-119 may stabilize and improve NMJ function in patients with SMA, reducing muscle weakness and fatigability, and improving quality of life.
- Conditions
- Spinal Muscular Atrophy (SMA)
- Being tested
- ARGX-119 IV, Placebo IV
- Keywords
- Spinal Muscular Atrophy, Pediatric, Muscle Function, Fatigability, SMA, ambulant
- Medical subject headings
- Muscular Atrophy, Spinal
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
ARGX-119 IVBiological
Intravenous infusion of ARGX-119
Placebo IVOther
Intravenous infusion of placebo
| Study group | Role | What they receive |
|---|---|---|
| DBTP - ARGX-119 IV | Experimental | Participants receive ARGX-119 IV during the DBTP Receives: Biological: ARGX-119 IV |
| DBTP - Placebo IV | Placebo comparator | Participants receive placebo IV during the DBTP Receives: Other: Placebo IV |
| ATEP - ARGX-119 IV | Placebo comparator | Participants receive ARGX-119 IV during the ATEP. Participants from ARGX-119 IV arm in the DBTP will receive placebo once to maintain the DBTP blinding Receives: Biological: ARGX-119 IV; Other: Placebo IV |
What is being measured
The primary outcome is the main question the study is designed to answer.
Incidence of AEs
Adverse Events
Measured: Up to 124 weeks
Incidence of SAEs
Serious Adverse Events
Measured: Up to 124 weeks
Change in RHS total score from baseline to week 24 of the double blinded treatment period (DBTP)
The RHS (Revised Hammersmith Scale) is a validated 36-item scale developed to evaluate the spectrum of gross motor function. Maximum total score; 69 (optimal motor function)
Measured: Up to 24 weeks
Secondary outcomes (3)
Change from baseline over time for the 6MWT - distance and fatigue index
In the 6MWT (6-minute walk test) participants will be instructed to walk as fast as possible without jogging or running along a 25- meter linearly marked course for 6 minutes without using walking devices or assistance. Distance walked over the entire 6-minute period, and other parameters, will be determined
Measured: Up to 124 weeks
ARGX-119 serum concentrations over time
ARGX-119 serum concentrations over time
Measured: Up to 124 weeks
Incidence of antidrug antibodies (ADA) against ARGX-119
Incidence of antidrug antibodies (ADA) against ARGX-119
Measured: Up to 124 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted17 Dec 2025
- Study start19 Dec 2025
- Primary completion28 May 2029 (estimated)
- Study completion28 May 2029 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Spinal Muscular Atrophy (SMA)Studies of the same condition, open and under way.
- More trials run by argenxThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Double blind
- Who is masked
- Participant, Investigator
- Enrolment
- 60 participants (estimated)
Sponsor and investigators
- Lead sponsor
- argenx
- Sponsor type
- Industry (pharma, biotech, devices)
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07287982
- Sponsor's protocol ID
- ARGX-119-24-SMA-2001
- Other IDs
- 2025-523496-32-00, 2025
- Acronym
- Sparkle
- Status last verified
- Sep 2026
- First submitted
- 15 Dec 2025
- Last updated
- 8 Oct 2026
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No