Clinical trial NCT05825131: Natural History Study of Participants With Sanfilippo Syndrome Type IIIC
Official title: A Combination Retrospective and Prospective Natural History Study of Participants With Sanfilippo Syndrome Mucopolysaccharidosis Type IIIC (MPS IIIC)
Study type: OBSERVATIONAL
Overall status: RECRUITING
Conditions: Sanfilippo Syndrome Type C
Keywords: Sanfilippo syndrome type C
Mucopolysaccharidosis type III C
MPS IIIC
Lead sponsor: Phoenix Nest
Sponsor class: INDUSTRY
Collaborators: name: Vaincres Les Maladies Lysosomales
name: Association Sanfilippo Sud
name: Aparito Ltd.
First posted: 2023-04-24
Enrollment: 30
Sex: ALL
Minimum age (years): 12
Standard ages: CHILD
ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: COHORT
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: Patients with a documented diagnosis of Sanfilippo syndrome type C and who are currently untreated with investigational products (drugs/device) for this disease.

Brief summary: This study is planned to document, through retrospective and prospective data collection, syndrome progression in children and young adults with MPS IIIC.

Detailed description: 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

Eligibility 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

Primary outcomes:
measure: Change From Baseline in Development Quotient (DQ) Using Bayley Scales of Infant Development Assessment Fourth Edition
timeFrame: Baseline, 12 months and 24 months
measure: Change From Baseline in Vineland Adaptive Behavior Scales Second Edition (VABS-II) Development Quotient (DQ) Score
timeFrame: Baseline, 12 months and 24 months
Secondary outcomes:
measure: Change From Baseline on the Color Trail Test Time Score
timeFrame: Baseline, 12 months and 24 months
measure: Change From Baseline of Regional Brain Volumes
timeFrame: Baseline, 12 months and 24 months
measure: Change From Baseline on the Assessment of Behavioral Changes in Sanfilippo (ABCS)
timeFrame: Baseline, 6 months, 12 months, 18 months, 24 months
measure: Change From Baseline on the Functional Abilities Descriptive Analysis of Type C- Recording Application for Real-world Evidence (C-RARE)
timeFrame: Baseline, 6 months, 12 months, 18 months, 24 months
measure: Change From Baseline on the Peabody Picture Vocabulary Test, Fifth Edition
timeFrame: Baseline, 12 months, 24 months
measure: Change From Baseline on the Expressive Vocabulary Test Third Edition
timeFrame: Baseline, 12 months, 24 months
measure: Change From Baseline in Speech Through Picture Description
timeFrame: Baseline, 12 months, 24 months
Other outcomes:
Locations:
city: Dallas
country: United States
facility: The University of Texas Southwestern Medical Center
state: Texas
city: Bron
country: France
facility: Hospices Civils De Lyon
Study officials:
affiliation: Hospices Civils de Lyon
name: Nathalie Guffon, MD
role: PRINCIPAL_INVESTIGATOR
References: