Observational Study in Patients With Cyclin-dependent Kinase-like 5 Deficiency Disorder

Study Overview
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Brief Summary
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Observational, noninterventional, 3-year study to examine the presence of detectable differences in neurocognitive, developmental, motor, neurophysiologic, and quality of life measures over time in patients with cyclin-dependent kinase-like 5 deficiency disorder.

Detailed Description
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This is an observational study to examine the presence of detectable differences in neurocognitive, developmental, motor, neurophysiologic, and quality of life measures over time in approximately up to 100 patients aged birth to 55 years and diagnosed with cyclin-dependent kinase-like 5 deficiency disorder. Operational performance across age groups and languages will be assessed throughout the study, and Baseline cohort characteristics will be assessed throughout enrollment.

Official Title
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Endpoint Enabling Study of Cyclin-dependent Kinase-like 5 (CDKL5) Deficiency Disorder (CDD)

Conditions
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Cyclin-Dependent Kinase-Like 5 Deficiency Disorder

Intervention / Treatment
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* Other: No intervention; observational


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Documented diagnosis of Cyclin-dependent Kinase-like 5 (CDKL5) deficiency disorder with pathogenic or likely pathogenic of CDKL5 variants Ages newborn to 55 years old Parent/Caregiver who is willing and capable of providing written informed consent Parent/caregiver lives with or has daily contact with study participant and able to provide consistent information across the study Exclusion Criteria: Any clinically significant neurocognitive deficit not attributable to Cyclin-dependent Kinase-like 5 (CDKL5) deficiency disorder or a secondary cause that may, in the opinion of the investigator, confound interpretation of study results (e.g., extreme prematurity, other genetic variants, unclassified CDKL5 variant, abnormal brain imaging, imaging and/or injury not otherwise attributable to CDD). Any condition that, in the opinion of the investigator, would put the patient at undue risk or make it unsafe for the patient to participate Any condition which would make the individual or the caregiver, in the opinion of the investigator, unsuitable for the study

Ages Eligible for Study
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Maximum Age: 55 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| 0-2 Years of Age<br>Patients from birth to 2 years of age at time of study entry | Other: No intervention; observational<br>* No intervention; observational<br>|
| 3-5 Years of Age<br>Patients aged 3 to 5 years at time of study entry | Other: No intervention; observational<br>* No intervention; observational<br>|
| 6-12 Years of Age<br>Patients aged 6 to 12 years at time of study entry | Other: No intervention; observational<br>* No intervention; observational<br>|
| 13-55 Years of Age<br>Patients aged 13 to 55 years at time of study entry | Other: No intervention; observational<br>* No intervention; observational<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Bayley Scale of Infant and Toddler Development, Fourth Edition (BSID-4) | Suitability of this cognition and global development scale in CDD will be assessed based on the number of tests completed, ceiling/floor effect and variance estimate. | Baseline | 
| Vineland 3 | Suitability of this adaptive behavior scale in CDD will be assessed based on the number of tests completed, ceiling/floor effect and variance estimate. | Baseline | 
| Gross Motor Function Measure (GMFM) | Suitability of this motor function scale in CDD will be assessed based on the number of tests completed, ceiling/floor effect and variance estimate. | Baseline | 
| Sleep Disturbance Scale for Children (SDSC) | Suitability of this sleep quality scale in CDD will be assessed based on the number of tests completed, ceiling/floor effect and variance estimate. | Baseline | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Changes in test results over time. |  | 36 months | 
| Correlations between age and test results. |  | 36 months | 
| Correlations between gender and test results. |  | 36 months | 
| Correlation between test results and seizure severity. |  | 36 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Cyclin-Dependent Kinase-Like 5 Deficiency Disorder, CDKL5, CDD