An observational study in Neuronal Ceroid-Lipofuscinoses, Neuronal Ceroid Lipofuscinosis CLN2 and Spinocerebellar Ataxia, Autosomal Recessive 7, sponsored by Children's Hospital of Orange County. Active, not recruiting at 1 site in United States. Open to participants aged 4 Years and older. Per ClinicalTrials.gov, last updated 2026-04-08.
Sponsored by Children's Hospital of Orange County · Observational
The purpose of this study is to gather information on the possible symptoms that patients with atypical neuronal ceroid lipofuscinosis type 2 (also known as aTPP1 or atypical tripeptidyl peptidase deficiency) have and how they change over time.
This study aims characterize the natural history of atypical TPP1 deficiency patients via longitudinal multidisciplinary assessments.
Multifaceted clinical, laboratory, imaging, and diagnostic assessments will be performed at regular intervals upon enrolled aTPP1 deficiency patients, collated, and analyzed over a three-year longitudinal period.
46 studies on the registry are indexed under Neuronal Ceroid-Lipofuscinoses; 12 are open to participants now.
This study's enrollment of 5 is below the median of 49 across 22 observational studies indexed under Neuronal Ceroid-Lipofuscinoses.
Browse Neuronal Ceroid-Lipofuscinoses studies →Children's Hospital of Orange County is the lead sponsor of 17 studies on the registry; 10 are open to participants now.
Counted across the registry records on this site, refreshed daily.
Any patient with documented TPP1 enzymatic deficiency or TPP1 sequence variants with onset of first symptom after 4 years of age
Exclusion Criteria:
CLN2 Disease Severity Scoring
Modified Hamburg Rating Scale. The rating scale consists of two domains (motor function, language). Within each domain, a score from 0 to 3 is assigned and overall scores are calculated by summing the domain scores for final rating of 0 (severely impaired) to 6 (normal).
Time frame: At baseline and every 3 months afterwards, up to 3 years
Electroretinogram (ERG)
Standard ERG will be performed to measure function of cones and rods of the inner and outer photoreceptor layers which amplitudes are typically decreased in classical TPP1 deficiency.
Time frame: At baseline and every 6 months afterwards, up to 3 years
Optical Coherence Tomography (OCT)
OCT is non-invasive, quantitative measurement of inner and outer photoreceptor layer thicknesses.
Time frame: At baseline and every 6 months afterwards, up to 3 years
Gait Assessment
Gait assessment is acquired utilizing infrared sensors applied to participant's clothing and will include collection of walking speed, cadence, swing phase, stride length and time, walking base width, stance phase, and double limb support phase.
Time frame: At baseline and every 6 months afterwards, up to 3 years
Brain Magnetic Resonance Imaging (MRI)
Pre/post-contrast images will be acquired to perform volumetric studies and white matter assessment.
Time frame: At baseline and every 12 months afterwards, up to 3 years
Electroencephalography (EEG)
EEG will be obtained and analyzed for changes that may be distinctive for TPP1 deficiency. Evaluation of background activity, mild/moderate/severe slowing for age.
Time frame: At baseline and every 12 months afterwards, up to 3 years
Electroencephalography (EEG)
EEG will be obtained and analyzed for changes that may be distinctive for TPP1 deficiency. Interictal discharges: location, focal/generalized, discharge burden.
Time frame: At baseline and every 12 months afterwards, up to 3 years
Electroencephalography (EEG)
Seizures.
Time frame: At baseline and every 12 months afterwards, up to 3 years
Electroencephalography (EEG)
Photoparoxysmal response: present/absent
Time frame: At baseline and every 12 months afterwards, up to 3 years
Cognitive Assessment, Wechsler Intelligence Scale for Children version 4 (WISC-IV)
WISC-IV will generate a full scale of intelligence quotient and five primary index scores: Verbal Comprehension, Visual Spatial, Fluid Reasoning, Working Memory, and Processing Speed. The WAIS-IV is scored by summing the raw scores for each subtest; each raw subtest score is then converted to a scaled scored. They are then combined to create a Full Scale IQ Index score. Test takers will also be given a score on the General Ability Index (GAI).
Time frame: At baseline and every 12 months afterwards, up to 3 years
CSF Testing
Standard laboratory testing and biobanking / storage of remaining CSF (via Ommaya if on enzyme replacement; via lumbar puncture if not on enzyme replacement)
Time frame: At baseline and every 3 months afterwards, up to 3 years
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Children's Hospital of Orange County