Longitudinal Assessment of Atypical Tripeptidyl Peptidase 1 Enzyme Deficiency Patients

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 4 years and older
• All sexes
• No healthy volunteers
• Child, Adult, Older adult

Study population: Any patient with documented TPP1 enzymatic deficiency or TPP1 sequence variants with onset of first symptom after 4 years of age

Trial locations and contacts

1 site in 1 country.

About this study

Official title: Longitudinal Assessment of Atypical Tripeptidyl Peptidase 1 Enzyme Deficiency (Neuronal Ceroid Lipofuscinosis Type 2) Patients

Conditions

Neuronal Ceroid-Lipofuscinoses, Neuronal Ceroid Lipofuscinosis CLN2, Spinocerebellar Ataxia, Autosomal Recessive 7

Keywords

Neuronal Ceroid Lipofuscinosis, Atypical CLN2 Disease, Natural History

Medical subject headings

Neuronal Ceroid-Lipofuscinoses, Spinocerebellar Ataxia, Autosomal Recessive 7

What is being measured

The primary outcome is the main question the study is designed to answer.

1. 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).

   Measured: At baseline and every 3 months afterwards, up to 3 years

2. 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.

   Measured: At baseline and every 6 months afterwards, up to 3 years

3. Optical Coherence Tomography (OCT)

   OCT is non-invasive, quantitative measurement of inner and outer photoreceptor layer thicknesses.

   Measured: At baseline and every 6 months afterwards, up to 3 years

4. 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.

   Measured: At baseline and every 6 months afterwards, up to 3 years

5. Brain Magnetic Resonance Imaging (MRI)

   Pre/post-contrast images will be acquired to perform volumetric studies and white matter assessment.

   Measured: At baseline and every 12 months afterwards, up to 3 years

6. 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.

   Measured: At baseline and every 12 months afterwards, up to 3 years

7. Electroencephalography (EEG)

   EEG will be obtained and analyzed for changes that may be distinctive for TPP1 deficiency. Interictal discharges: location, focal/generalized, discharge burden.

   Measured: At baseline and every 12 months afterwards, up to 3 years

8. Electroencephalography (EEG)

   Seizures.

   Measured: At baseline and every 12 months afterwards, up to 3 years

9. Electroencephalography (EEG)

   Photoparoxysmal response: present/absent

   Measured: At baseline and every 12 months afterwards, up to 3 years

10. 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).

    Measured: At baseline and every 12 months afterwards, up to 3 years

11. 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)

    Measured: At baseline and every 3 months afterwards, up to 3 years

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

1. First posted23 Sep 2019
2. Study start1 Nov 2019
3. Primary completionDec 2026 (estimated)
4. Study completionDec 2026 (estimated)

Resources

• Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
• Other trials for Neuronal Ceroid-LipofuscinosesStudies of the same condition, open and under way.
• 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.