ClinicalTrials.gov record NCT05825131
Natural History Study of Participants With Sanfilippo Syndrome Type IIIC
A Combination Retrospective and Prospective Natural History Study of Participants With Sanfilippo Syndrome Mucopolysaccharidosis Type IIIC (MPS IIIC)
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴
AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.
This observational natural history study combines a review of past medical records with ongoing clinical and remote data collection to document how MPS IIIC progresses. Participants may attend yearly clinic visits for neurocognitive, developmental, behavioral, biochemical and imaging assessments, and caregivers complete home video tasks and questionnaires using the C-RARE app at 6-month intervals. The study is for people with a confirmed diagnosis of Sanfilippo syndrome type C (MPS IIIC).
What it is studying. The study aims to document how MPS IIIC changes over time across behavior, cognition, mobility, vision, hearing, speech, and language, and to identify clinical measures (endpoints) that could be used in future trials.
What the researchers hope to learn. To enhance understanding of the natural history and progression of MPS IIIC on behavior, cognitive abilities, mobility, vision, hearing, speech, and expressive and receptive language. To define and categorize clinical endpoints that may be used in future clinical trials.
What this study is about
The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.
This study is planned to document, through retrospective and prospective data collection, syndrome progression in children and young adults with MPS IIIC.
Eligibility
The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.
Inclusion criteria
- Confirmed diagnosis of Sanfilippo syndrome type C disease by all of the following:
- Deficiency in heparan-alpha-glucosaminide N-acetyltransferase enzyme activity
- Has presented with signs/symptoms consistent with Sanfilippo syndrome type C, or, for individuals who have not presented with signs/symptoms of disease (eg, siblings of known patients), the determination of eligibility will be at the discretion of the Sponsor in conjunction with the site Investigator
- Genomic DNA analysis demonstrating homozygous or compound heterozygous, pathogenic and/or potentially pathogenic variants in the HGSNAT gene
- Accumulated GAG HS in urine
- Written informed consent from parent or legal guardian and assent from patient, if required
- Parent/legal guardian willing to accompany the patient to all study visits
- Ability to comply with protocol requirements, in the opinion of the Investigator
- Negative urine pregnancy test at screening (nonsterile females of childbearing potential only).
- Functional abilities:
- Able to take food or liquid by mouth, able to walk with or without assistance.
- Has an age equivalent on the Vineland Adaptive Behavior Scales (VABS) of ≥1 year.
Exclusion criteria
- Patients who meet any of the following criteria will not be eligible to participate in the study:
- Have received an investigational drug within 30 days prior to the Baseline Visit
- Concomitant illness or medical condition or extenuating circumstance that, in the opinion of the Investigator, might compromise the patient's ability to comply with protocol requirements, the patient's well-being or safety, or the interpretability of the patient's clinical data
- The presence of significant non-MPS IIIC-related CNS impairment or behavioral disturbances that would confound the scientific rigor or interpretation of results of the study
Study description and what participation involves
The study's detailed description, as published on ClinicalTrials.gov.
Show the detailed description from the registry
This is a multi-center, natural history study of subjects with Sanfilippo syndrome type C or MPS IIIC. This study will combine a retrospective review of medical records and an ongoing collection of clinical data on an observational basis. Real-world data will be collected at home using a recording device. Participants will be asked to attend clinic visits in person on a yearly basis. In clinic visits will include neurocognitive, developmental, behavioral, biochemical, imaging measures as well as retrospective medical record analysis. At 6-month intervals between clinic visits, participants will be contacted remotely for some safety assessments (e.g., collecting information about concomitant medications, concurrent illnesses, and procedure-related adverse events [AEs] and serious AEs [SAEs] since last clinic visit). At 6-month intervals, caregivers will complete questionnaires and record home video assessments using a dedicated, compliant study application (app) called C-RARE (Recording Application for Real-World Evidence). The C-RARE app consists of 9 tasks of Activities of Daily Living and socialization as well as three parent reported Sanfilippo specific questionnaires. The objectives of this study are:
- To enhance the understanding of the natural history and progression of MPS IIIC syndrome on behavior, cognitive abilities, mobility, vision, hearing, speech, and expressive and receptive language
- To define and categorize clinical endpoints that may be used in future clinical trials
AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴
AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.
Participants typically attend yearly in‑person clinic visits (including baseline, 12‑month and 24‑month assessments) for neurocognitive, developmental and behavioral testing, biochemical sample collection, and brain MRI, and the study team will review medical records. Every six months caregivers are contacted for safety checks and complete questionnaires and home video tasks using the C‑RARE app (nine activities of daily living tasks plus three Sanfilippo‑specific questionnaires). Some people may take part only by remote video plus chart review, or only by retrospective chart review (including deceased patients). Parent/guardian consent and willingness to attend visits are required, and nonsterile females of childbearing potential must have a negative urine pregnancy test at screening.
How the study is structured. An observational natural history study that combines retrospective medical-record review with prospective follow-up. There are three participation options: in-person yearly clinic visits with assessments, remote-only participation using the C-RARE home video app plus chart review, or chart-review only (including records of deceased patients). Caregivers are contacted about every 6 months for remote assessments and questionnaires; the planned follow-up period is up to 2 years for prospective data.
Questions you could ask
These questions are suggestions for a conversation with the study team or your own clinician, not advice.
- This is an observational study, so the study itself gives no treatment. What would taking part involve for me, and would it change my usual care?
- The listed sites are in France, United States. Is any of them reachable for me, and does the study help with travel?
- Which of the eligibility criteria would need to be checked with tests before I could join?
More on Sanfilippo syndrome
Important dates
- Study start
- Nov 10, 2024
- Primary completion
- Jul 30, 2028 (estimated)
- Study completion
- Dec 1, 2028 (estimated)
- Target enrollment
- 30 participants (estimated)
- Last updated on registry
- May 12, 2026
- Data verified
- Oct 10, 2026
Sponsor and research team
The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.
- Lead sponsor
- Phoenix Nest
- Collaborators
- Vaincres Les Maladies Lysosomales
- Association Sanfilippo Sud
- Aparito Ltd.
Central study contact
If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.
- Nathalie Reynes 📞 04 72 12 95 37 ✉ nathalie.reynes@chu-lyon.fr
- Nathalie Guffon, MD 📞 04 72 12 95 37 ✉ nathalie.guffon-fouilhoux@chu-lyon.fr
Participating sites (2)
- The University of Texas Southwestern Medical CenterRecruiting
Dallas, Texas, 75390 · United States
- Alyssa Boudreau Site Coordinator · 214-456-2106 · Alyssa.Boudreau@utsouthwestern.edu
- Holly Lawrence · Holly.Lawrence@utsouthwestern.edu
- Berge Minassian, MD
- Hospices Civils De LyonRecruiting
Bron, 690007539 · France
Terms used on this page · explanations by MedicalUpdates.ai
- Sponsor
- The organisation or person that initiates the study and has authority over it. The sponsor may be a company, hospital, university, government agency or individual, and is not necessarily the organisation that funds the study.
- Written informed consent
- The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
- legal guardian
- A person who is legally allowed to make decisions, including consent to research, on behalf of someone who cannot consent for themselves.
- assent
- A child's or dependent adult's agreement to take part, given alongside the formal consent of a parent or legal representative.
- at screening
- The checks done before enrolment to see whether a person qualifies, such as tests, scans or a review of medical history.
- childbearing potential
- Studies often ask participants who could become pregnant, or could father a child, to use contraception during the study and for a period afterwards, because the effect of the treatment on a pregnancy is unknown.
- investigational drug
- A treatment that is being tested and has not been approved for this use. It may be approved for a different condition. Being studied does not mean it works or is available outside the study.
- Baseline
- Measurements taken at the start of the study, before any study treatment, so that later results can be compared with them.
- Inclusion Criteria
- The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
- Exclusion Criteria
- The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.
- natural history study
- A study that follows how a condition changes over time without assigning an experimental treatment. It may involve study visits and tests, and is often used to plan future trials.
- concomitant medications
- Other medicines a participant takes during the study. Some must be reported; some are restricted.
- adverse events
- Any unwanted medical problem that happens during a study, whether or not it was caused by the treatment. A 'serious' adverse event is one that meets specific criteria, such as causing death, being life-threatening, requiring or prolonging hospital admission, causing significant disability, or another medically important outcome.
- endpoints
- Something the study measures to judge its results, such as a symptom score, a blood test or survival. Outcomes are grouped as primary, secondary and sometimes exploratory.
The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.
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