Relevant Outcome Measures for Creatine Transporter Deficiency Patient
Condition(s) studied
Investigational drug(s) / intervention(s)
Clinical endpoints: 1. Number of epileptic seizures 2. Change in antiepileptic treatment (increase or decrease) 3. Visual analogical scale on a target symptom defined with the parents, 4. CGI, 5. Actimetry data over 24 hours, 6. Podometry data over 24 hours, 7. 6 minutes' walk test, 8. Clinical examination 9. Feasibility of performing an MRI without any anesthesia on a mock scanner
Parental questionnaires: 10- Adaptive assessment with Vineland Adaptive Behavior scale II, 11- Mac Arthur questionnaire regarding language, 12- Pervasive Development Disorder in Mentally Retarded persons Scale (PDD-MRS), 13- Dunn sensory profile, 14- Aberrant Behavior Checklist, 15- Nisonger Child Behavior Rating form, 16- Social Responsiveness Scale 2, 17- Scales assessing the impact on primary caregiver (CBI-M/ Beach Center Family QOL)
Quality of life scale: 18- Quality of life scale (PedsQL 4.0 for children or San Martin scale if the patient is older than 18)
Cognitive assessments: 19- 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 20- CPM-BF 21- Simple reasoning task on tablet (match-to-sample task) 22- Implicit rules learning (modified Brixton), 23- 4 sub-tests from the WPPSI-IV ("zoo location" to assess spatial memory, "block design" to assess visuo-constructive abilities, "bug search" , "cancellation"), 24- Attention assessment (4 sub-tests from KITTAP: alert, go/no go, flexibility, divided attention), 25- Elementary visuo-spatial perception (on tablets)
Language assessments: 26- EXALANG 3-6 (10 sub-tests testing for expressive and receptive language assessments), 27- PPVT-5 (receptive vocabulary), EVT-3 (expressive vocabulary), 28- Automatic language analysis (during a 10 minutes interaction, play).
Motor assessments: 29- Kinematic task (specifically designed), 30- Purdue-Pegboard test, 31- Renzi test
Social assessments: 32- Eye-tracking analysis of social visual scenes and social preference index (movies), 33- theory of mind assessment, 34- ADOS scale (Autism Spectrum Disorder), 35- sensitivity to inequality, 36- pro-social behaviors (help of the psychologist)
3T MRI: 37- Structural, metabolic and functional data
Cardiac assessments: 38- ECG 39- Ultrasound
Biological collection: 40- Blood sample 41- Urinary sample 42- Superficial skin biopsy
Study 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.
Eligibility
Primary outcome measure(s)
- Clinical endpoints : number of epileptic seizures — Up to 90 Days
Number of epileptic seizures - Clinical endpoints : antiepileptic treatment — For 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 : Visual analogical scale — Up to 90 Days
Visual analogical scale on a target symptom defined with the parents, - Clinical endpoints : actimetry — Up to 90 Days
Actimetry data over 48 hours - Clinical endpoints : podometry — Up to 90 Days
Podometry data over 24 hours - Clinical endpoints : walk test — Up to 90 Days
6 minutes' walk test - Clinical endpoints : Clinical examination — For 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 MRI — For 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 : Vineland Adaptive Behavior scale II — For 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 : Mac Arthur questionnaire — For 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-MRS — For 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 : Dunn sensory profile — For all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V3 (Day30) and V7 (Day90).
Dunn sensory profile - Parental questionnaires : Aberrant Behavior Checklist — For 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 - Parental questionnaires : Nisonger Child Behavior Rating form — For all 24 CTD patients: at V1 (Day1/Day2), For 9 out 24 CTD patients: repeated at V7 (Day90).
Nisonger Child Behavior Rating form - Parental questionnaires : Social Responsiveness Scale 2 — For 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 caregiver — For 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) - Quality of life scale — For 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 : Leiter 3 scale — For 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-BF — For 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 : reasoning task — For 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) - Cognitive assessments : Implicit rules learning — For 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), - Cognitive assessments : WPPSI-IV — For 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 assessment — For 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), - Cognitive assessments : Elementary visuo-spatial perception — For 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) - Language assessments : EXALANG 3-6 — For 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 - Language assessments : vocabulary — For 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, - Language assessments : Automatic language analysis — For 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 : Kinematic task — CTD patients : performed at V1 (Day1/Day2). Controls: Motor assessment at V1 (Day 1)
Kinematic task (specifically designed) - Motor assessments : Purdue-Pegboard test — CTD patients : performed at V1 (Day1/Day2), V3(Day30), and V7 (Day90). Controls: Motor assessment at V1 (Day 1)
Purdue-Pegboard test - Motor assessments : Renzi test — CTD patients : performed at V1 (Day1/Day2), V3(Day30), and V7 (Day90). Controls: Motor assessment at V1 (Day 1)
Renzi test - Social assessments : Eye-tracking — CTD 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 : Theory of mind assessment — CTD patients : performed at V1 (Day1/Day2). Controls : Social assessment at V1(Day1)
Theory of mind assessment - 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) - Social assessments : Sensitivity to inequality — CTD patients : performed at V1 (Day1/Day2). Controls : Social assessment at V1(Day1)
Sensitivity to inequality - 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)
Trial sites (1)
| Facility | City | Region | Status |
|---|---|---|---|
| Woman, mother and child hospital, Hospices Civils de Lyon | Bron | France | Recruiting |
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