Observing the progression of Sanfilippo Syndrome Type C in patients

A Combination Retrospective and Prospective Natural History Study of Participants With Sanfilippo Syndrome Mucopolysaccharidosis Type IIIC (MPS IIIC)

Observational Phoenix Nest · NCT05825131

This study is tracking how Sanfilippo Syndrome Type C affects children and young adults over time to better understand its impact on their health and development.

Quick facts

Study typeObservational
Enrollment30 (estimated)
Ages12 Months and up
SexAll
SponsorPhoenix Nest Industry-sponsored
Locations2 sites (Dallas, Texas and 1 other locations)
Trial IDNCT05825131 on ClinicalTrials.gov

What this trial studies

This observational study aims to document the natural history of Sanfilippo Syndrome Type C (MPS IIIC) through both retrospective and prospective data collection. Participants, including children and young adults, will undergo yearly clinic visits for comprehensive assessments, including neurocognitive and behavioral evaluations. Additionally, caregivers will use a dedicated app to record home video assessments and complete questionnaires every six months, allowing for continuous monitoring of the condition's progression. The study seeks to enhance understanding of the syndrome's impact on various aspects of health and development.

Who should consider this trial

Good fit: Ideal candidates include individuals with a confirmed diagnosis of Sanfilippo Syndrome Type C, characterized by specific enzyme deficiencies and genetic markers.

Not a fit: Patients without a confirmed diagnosis of Sanfilippo Syndrome Type C or those who do not meet the eligibility criteria may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide valuable insights into the progression of Sanfilippo Syndrome Type C, potentially leading to improved management strategies for affected patients.

How similar studies have performed: While this study focuses on a specific subtype of Sanfilippo syndrome, similar observational studies have successfully documented the natural history of other lysosomal storage disorders.

Eligibility criteria

Show full inclusion / exclusion criteria
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

Where this trial is running

Dallas, Texas and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Sanfilippo Syndrome Type CSanfilippo syndrome type CMucopolysaccharidosis type III CMPS IIIC
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.