MedPath

Relevant Outcome Measures for Creatine Transporter Deficiency Patient

Not Applicable
Recruiting
Conditions
Creatine Transporter Defect
Interventions
Other: Clinical endpoints
Other: Parental questionnaires
Other: Cognitive assessments
Other: Quality of life scale
Other: Language assessments
Other: Motor assessments
Other: Social assessments
Other: 3T MRI
Other: Cardiac assessments
Other: Biological collection
Registration Number
NCT06018519
Lead Sponsor
Hospices Civils de Lyon
Brief Summary

Creatine transport deficiency (CTD) is a rare genetic disorder related to pathogenic variants in the SLC6A8 gene, located on chromosome Xq28. Clinical diagnosis of CTD is based on clinical presentation, an increased urinary creatine/creatinine ratio and a severe decreased creatine peak on 1H-MRS magnetic resonance spectroscopy.

A retrospective study with questionnaires identified that most CTD patients had moderate to severe intellectual disability. Less than one third of patients were able to speak in sentences. Seizures were present in 59% of the patients. 41% had autistic features. Motor dysfunction was mentioned in 58%, and gastrointestinal symptoms were reported in 35% of the patients.

Several new therapeutic avenues are currently emerging in this disease for which no treatment has been available until now : cyclocreatine (interesting but unfortunately with very little clinical applicability due to its toxicity; dodecyl creatine ester incorporated into lipid nanocapsules with intranasal administration; pharmaco-chaperoning (for the folding-deficient creatine transporter variants, Ultragenyx pharmaceuticals new prodrug designed to deliver creatine to the brain (UX068). These new pharmacological treatment options may offer future opportunities to improve cognition in CTD patients.

A key issue is to determine outcome measures that are accessible to these patients, despite the importance of their cognitive deficit. In a preliminary study (on 31 CTD patients), investigators showed for example, that 75% of patients were unable to perform a Wechsler scale, which is one of the most used neuropsychological test to determine patient IQ (intelligence quotient). Most of the existing cognitive tests were developed to distinguish typically developing persons and ID (intellectual disability) patients, leading to a floor effect in the latter who systematically fail these tests. Therefore, these tests are not adapted to capture the potential effect of a drug in ID patient group. The identification of reliable and sensitive outcome measures for use in clinical trials in ID patients was recognized as a priority in a meeting convened by the NIH. N-of-1 trials (also called Single-Case Experimental Designs or SCEDs) appear of great interest for rare diseases, statistical power coming from the number of repeated measures, which leads to choose outcome measures that can be repeated multiple times.

This innovative study will allow to efficiently preparing future therapeutic trials, by specifying the phenotype of the patients, and by determining the most adapted outcome measures taking into account their cognitive deficiency and the type of experimental design to be used in the context of rare diseases.

Detailed Description

Not available

Recruitment & Eligibility

Status
RECRUITING
Sex
All
Target Recruitment
197
Inclusion Criteria

Male CTD patients (n=24)

  • Male CTD patients having a confirmed mutation in the SLC6A8 gene,
  • Aged > 5 to < 35 years
  • Whose maternal language is French,
  • Having signed the informed consent and/or for whom parents/legal guardian have signed the informed consent,
  • Affiliated to national Health Insurance system or parents/legal guardian affiliated to national health insurance system.

Female CTD patients (n=15)

  • Female CTD patients having a confirmed mutation in the SLC6A8 gene,
  • Aged > 5 to < 60 years,
  • Whose maternal language is French,
  • Having signed the informed consent and/or for whom parents/legal guardian have signed the informed consent.
  • Affiliated to national Health Insurance system (sécurité sociale) or parents/legal guardian affiliated to national health insurance system

Sex- and chronological age-matched controls (n=24)

  • Male
  • Aged > 5 to < 35 years
  • Whose maternal language is French,
  • Having signed the informed consent and/or for whom parents/legal guardian have signed the informed consent,
  • Affiliated to national health insurance system or parents/legal guardian affiliated to national health insurance system.

Sex- and chronological age-matched female controls (n=15)

  • female,
  • Aged > 5 to < 60 years,
  • Whose maternal language is French,
  • Having signed the informed consent and/or for whom parents/legal guardian have signed the informed consent
  • Affiliated to national Health Insurance system (sécurité sociale) or parents/legal guardian affiliated to national health insurance system

Sex- and mental age-matched controls (n=39)

  • Male and female
  • Aged > 2 to < 8 years
  • Whose maternal language is French,
  • For whom parents/legal guardian have signed the informed consent,
  • Affiliated to national health insurance system or parents/legal guardian affiliated to national health insurance system.

Typically developed children (n=80)

  • Male and female
  • Aged > 2 to < 8 years
  • Whose maternal language is French,
  • For whom parents/legal guardian have signed the informed consent,
  • Affiliated to national health insurance system or parents/legal guardian affiliated to national health insurance system.

Non-inclusion Criteria:

CTD patients (n=39):

  • Having a contraindication to the MRI examination (people using a pacemaker or an insulin pump, people wearing a metal prosthesis or an intracerebral clip, and claustrophobic subjects),
  • Refusal of the subject and/or the subject's parents to be informed of possible abnormalities detected by MRI,
  • Refusal of the subject and/or the subject's parents/legal guardian to be informed of possible abnormalities detected during the cardiac assessment.

Sex- and chronological age-matched controls (n=39)

  • History of neurological or psychiatric disorder,
  • Repetition of a grade,
  • Learning disability requiring rehabilitation (speech therapy, psychomotor or oculomotor therapy),
  • For participants agreeing on performing the MRI examination, having a contraindication to the MRI examination (use of a pacemaker or an insulin pump, people wearing a metal prosthesis or an intracerebral clip, and claustrophobic subjects) and refusal of the subject and/or the subject's parents/legal guardian to be informed of possible abnormalities detected by MRI.

Sex- and mental age-matched controls (n=39)

  • History of neurological or psychiatric disorder,
  • Repetition of a grade,
  • Learning disability requiring rehabilitation (speech therapy, psychomotor or oculomotor therapy).

Typically developed children (n=80)

  • History of neurological or psychiatric disorder,
  • Repetition of a grade,
  • Learning disability requiring rehabilitation (speech therapy, psychomotor or oculomotor therapy).
Exclusion Criteria

Not provided

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Sex and chronological age matched controlsMotor assessmentsControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
Typically developed childrenLanguage assessmentsControl group 80 typically developed children aged \> 3 to \< 8 years, which corresponds to the mental age of CTD patients. 40 children aged \> 3 to \< 5 years, and 40 children aged \> 6 to \< 8 years will perform the newly developed outcome measures.
CTD patientsClinical endpointsCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
CTD patients3T MRICase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
CTD patientsBiological collectionCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
Sex and chronological age matched controlsClinical endpointsControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
Sex and chronological age matched controlsCognitive assessmentsControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
CTD patientsQuality of life scaleCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
CTD patientsMotor assessmentsCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
Sex and chronological age matched controls3T MRIControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
Sex and mental age matched controlsQuality of life scaleControl group 24 male, sex and mental age matched controls, aged \> 3 to \< 8 years
Sex and chronological age matched controlsQuality of life scaleControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
Sex and chronological age matched controlsLanguage assessmentsControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
Sex and chronological age matched controlsSocial assessmentsControl group 24 male, sex and chronological age matched controls, aged \> 5 to \< 35 years
Sex and mental age matched controlsSocial assessmentsControl group 24 male, sex and mental age matched controls, aged \> 3 to \< 8 years
CTD patientsCognitive assessmentsCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
CTD patientsSocial assessmentsCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
CTD patientsCardiac assessmentsCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
Sex and mental age matched controlsLanguage assessmentsControl group 24 male, sex and mental age matched controls, aged \> 3 to \< 8 years
CTD patientsParental questionnairesCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
CTD patientsLanguage assessmentsCase group 24 male CTD patients having a confirmed mutation in the SLC6A8 gene, aged \> 5 to \< 35 years.
Sex and mental age matched controlsCognitive assessmentsControl group 24 male, sex and mental age matched controls, aged \> 3 to \< 8 years
Typically developed childrenQuality of life scaleControl group 80 typically developed children aged \> 3 to \< 8 years, which corresponds to the mental age of CTD patients. 40 children aged \> 3 to \< 5 years, and 40 children aged \> 6 to \< 8 years will perform the newly developed outcome measures.
Typically developed childrenCognitive assessmentsControl group 80 typically developed children aged \> 3 to \< 8 years, which corresponds to the mental age of CTD patients. 40 children aged \> 3 to \< 5 years, and 40 children aged \> 6 to \< 8 years will perform the newly developed outcome measures.
Typically developed childrenMotor assessmentsControl group 80 typically developed children aged \> 3 to \< 8 years, which corresponds to the mental age of CTD patients. 40 children aged \> 3 to \< 5 years, and 40 children aged \> 6 to \< 8 years will perform the newly developed outcome measures.
Sex and mental age matched controlsParental questionnairesControl group 24 male, sex and mental age matched controls, aged \> 3 to \< 8 years
Sex and mental age matched controlsMotor assessmentsControl group 24 male, sex and mental age matched controls, aged \> 3 to \< 8 years
Typically developed childrenParental questionnairesControl group 80 typically developed children aged \> 3 to \< 8 years, which corresponds to the mental age of CTD patients. 40 children aged \> 3 to \< 5 years, and 40 children aged \> 6 to \< 8 years will perform the newly developed outcome measures.
Typically developed childrenSocial assessmentsControl group 80 typically developed children aged \> 3 to \< 8 years, which corresponds to the mental age of CTD patients. 40 children aged \> 3 to \< 5 years, and 40 children aged \> 6 to \< 8 years will perform the newly developed outcome measures.
Primary Outcome Measures
NameTimeMethod
Clinical endpoints : Visual analogical scaleUp to 90 Days

Visual analogical scale on a target symptom defined with the parents,

Clinical endpoints : walk testUp to 90 Days

6 minutes' walk test

Clinical endpoints : antiepileptic treatmentFor all 24 CTD patients: all examinations at V1 (Day 1/Day2) For 9 out of 24 CTD patients: examinations repeated every two weeks at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90).

Change in antiepileptic treatment (increase or decrease)

Clinical endpoints : Clinical examinationFor all 24 CTD patients: all examinations at V1 (Day 1/Day2) For 9 out of 24 CTD patients: examinations repeated every two weeks at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90).

Clinical examination

Clinical endpoints :Feasibility of performing an MRIFor all 24 CTD patients: all examinations at V1 (Day 1/Day2) For 9 out of 24 CTD patients: examinations repeated every two weeks at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90).

Feasibility of performing an MRI without any anesthesia on a mock scanner

Parental questionnaires : Dunn sensory profileFor all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V3 (Day30) and V7 (Day90).

Dunn sensory profile

Clinical endpoints : podometryUp to 90 Days

Podometry data over 24 hours

Parental questionnaires : Vineland Adaptive Behavior scale IIFor all 24 CTD patients: V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V7 (Day90).

Adaptive assessment with Vineland Adaptive Behavior scale II

Parental questionnaires : Nisonger Child Behavior Rating formFor all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V7 (Day90).

Nisonger Child Behavior Rating form

Quality of life scaleFor all 24 CTD patients: At V1 (Day1/Day2) For 9 out of 24 CTD patients: Repeated at V3 (Day30) and V7 (Day90).

Quality of life scale (PedsQL 4.0 for children or San Martin scale if the patient is older than 18)

Cognitive assessments : reasoning taskFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

Simple reasoning task on tablet (match-to-sample task)

Social assessments : Eye-trackingCTD patients : performed at V1 (Day1/Day2), V3 (Day30) and V7 (Day90). Controls : Social assessment at V1(Day1)

Eye-tracking analysis of social visual scenes and social preference index (movies)

Social assessments : ADOS scale (Autism Diagnostic Observation Scale)CTD patients : performed at V1 (Day1/Day2). Controls : Social assessment at V1(Day1)

ADOS scale (Autism Spectrum Disorder)

Clinical endpoints : number of epileptic seizuresUp to 90 Days

Number of epileptic seizures

Parental questionnaires : Aberrant Behavior ChecklistFor all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90).

Aberrant Behavior Checklist

Cognitive assessments : Leiter 3 scaleFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

Leiter 3 scale (4 cognitive sub-tests to be able to compute the non-verbal IQ and 2 non-verbal memory sub-tests) or Bayley 4 if Leiter 3 is not possible

Cognitive assessments : CPM-BFFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

CPM-BF : Raven's coloured Progressive Matrices

Cognitive assessments : Implicit rules learningFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

Implicit rules learning (modified Brixton),

Language assessments : EXALANG 3-6For all 24 CTD patients: performed at V1 (Day1/Day2). For 9 out of 24 CTD patients: repeated at V3 (Day30), and V7 (Day90). Controls: Language assessment at V1(Day 1)

EXALANG 3-6 - Computerized battery for the evaluation of oral and written language : 10 sub-tests testing for expressive and receptive language assessments

Clinical endpoints : actimetryUp to 90 Days

Actimetry data over 48 hours

Parental questionnaires : Mac Arthur questionnaireFor all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V3 (Day30) and V7 (Day90).

Mac Arthur questionnaire regarding language

Parental questionnaires : PDD-MRSFor all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V7 (Day90).

Pervasive Development Disorder in Mentally Retarded persons Scale (PDD-MRS)

Parental questionnaires : Social Responsiveness Scale 2For all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V7 (Day90).

Social Responsiveness Scale 2

Parental questionnaires : impact on primary caregiverFor all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V3 (Day30) and V7 (Day90).

Scales assessing the impact on primary caregiver (CBI-M/ Beach Center Family QOL)

Cognitive assessments : WPPSI-IVFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V3 (Day30) and V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

4 sub-tests from the WPPSI-IV ("zoo location" to assess spatial memory, "block design" to assess visuo-constructive abilities, "bug search" , "cancellation"),

Cognitive assessments : Attention assessmentFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V3 (Day30) and V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

Attention assessment (4 sub-tests from KITTAP: alert, go/no go, flexibility, divided attention),

Language assessments : Automatic language analysisFor all 24 CTD patients: performed at V1 (Day1/Day2). For 9 out of 24 CTD patients: repeated at V3 (Day30), and V7 (Day90). Controls: Language assessment at V1(Day 1)

Automatic language analysis (during a 10 minutes interaction, play).

Motor assessments : Renzi testCTD patients : performed at V1 (Day1/Day2), V3(Day30), and V7 (Day90). Controls: Motor assessment at V1 (Day 1)

Renzi test

Cognitive assessments : Elementary visuo-spatial perceptionFor the 24 CTD patients: at V1 (Day1/Day2), For 9 out of 24 CTD patients: repeated at V2 (Day15), V3 (Day30), V4 (Day45), V5 (Day60), V6 (Day75) and V7 (Day90). Controls: Cognitive assessment at V1(Day 1)

Elementary visuo-spatial perception (on tablets)

Motor assessments : Kinematic taskCTD patients : performed at V1 (Day1/Day2). Controls: Motor assessment at V1 (Day 1)

Kinematic task (specifically designed)

Motor assessments : Purdue-Pegboard testCTD patients : performed at V1 (Day1/Day2), V3(Day30), and V7 (Day90). Controls: Motor assessment at V1 (Day 1)

Purdue-Pegboard test

Social assessments : Sensitivity to inequalityCTD patients : performed at V1 (Day1/Day2). Controls : Social assessment at V1(Day1)

Sensitivity to inequality

Language assessments : vocabularyFor all 24 CTD patients: performed at V1 (Day1/Day2). For 9 out of 24 CTD patients: repeated at V3 (Day30), and V7 (Day90). Controls: Language assessment at V1(Day 1)

PPVT-5 : Peabody Picture Vocabulary Test Fifth Edition = receptive vocabulary, EVT-3 : Expressive Vocabulary Test third edition,

Social assessments : Theory of mind assessmentCTD patients : performed at V1 (Day1/Day2). Controls : Social assessment at V1(Day1)

Theory of mind assessment

Social assessments : Pro-social behaviors (help of the psychologist)CTD patients : performed at V1 (Day1/Day2). Controls : Social assessment at V1(Day1)

Pro-social behaviors (help of the psychologist)

Secondary Outcome Measures
NameTimeMethod
Biological collection : Urine sampleCTD patients: V1 (Day1/Day2)

Urine sample will be collected to create a collection of biological samples associated with clinical and genomic data from CTD patients. In the future this will be usefull for research labs to investigate new biomarkers (not identified yet) or to test for the efficiency of new therapeutic approaches in vitro (on cultivated fibroblasts or after the development of iPS cells or organoïds) in this rare disease.

Cardiac assessments : ElectrocardiogramCTD patients: V1 (Day1/Day2)

Electrocardiogram (ECG) will be performed to describe CTD patients cardiac profile (especially the risk of increased QTC and/or cardiac echography abnormality)

Cardiac assessments : UltrasoundCTD patients: V1 (Day1/Day2)

Cardiac Ultrasound will be performed to describe CTD patients cardiac profile (especially the risk of increased QTC and/or cardiac echography abnormality)

Biological collection : Blood sampleCTD patients: V1 (Day1/Day2)

Blood sample (plasma and peripheral blood mononuclear cells)

Biological collection : Superficial skin biopsyCTD patients: V1 (Day1/Day2)

Superficial skin biopsy will be performed to get cultivated fibroblasts to create a collection of biological samples associated with clinical and genomic data from CTD patients. In the future this will be usefull for research labs to investigate new biomarkers (not identified yet) or to test for the efficiency of new therapeutic approaches in vitro (on cultivated fibroblasts or after the development of iPS cells or organoïds) in this rare disease.

Neuroimaging (MRI)V1 (Day1/Day2)

The MRI will be performed to describe structural and functional neuroanatomical profile of CTD patient in comparison to chronological age-matched controls and variability in creatine peak assessment using MR spectroscopy

Trial Locations

Locations (1)

Woman, mother and child hospital, Hospices Civils de Lyon

🇫🇷

Bron, France

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