ClinicalTrials.gg
RecruitingNCT05558371ICCRNUpdated Dec 6, 2023

International CDKL5 Clinical Research Network

An observational study in CDKL5, CDKL5 Deficiency Disorder and CDD, sponsored by University of Colorado, Denver. Recruiting at 9 sites in 2 countries. Open to participants aged 1 Month to 100 Years. Per ClinicalTrials.gov, last updated 2023-12-06.

Sponsored by University of Colorado, Denver · Observational

From the registry’s dates

  • Primary completion was expected by Feb 2026, 8 months ago, but the record still lists the study as recruiting.
  • Started Feb 2021; still recruiting 5 years 8 months later.
Study type
Observational
Model
Cohort
Time perspective
Prospective
Enrollment
1,000
Ages
1 Month to 100 Years
Sex
All
01

Study summary

Pathogenic variants in the Cyclin-dependent kinase like 5 (CDKL5) gene cause CDKL5 deficiency disorder (CDD, MIM 300672, 105830), a severe developmental and epileptic encephalopathy associated with cognitive and motor impairments and cortical visual impairment. While capability for disease modifying therapies is accelerating, there is a critical barrier for clinical trial readiness that may result in failure of these therapies, not due to lack of efficacy but due to lack of validated outcome measures and biomarkers. The measures and biomarkers validated here will be adaptable to other developmental and epileptic encephalopathies.

Read the detailed description

Pathogenic variants in the Cyclin-dependent kinase like 5 (CDKL5) gene cause CDKL5 deficiency disorder (CDD, MIM 300672, 105830) a severe developmental and epileptic encephalopathy (DEE) associated with cognitive and motor dysfunction and cortical visual impairment. Recent data suggest CDD is one of the most common genetic causes of DEE. Work in CDD animal models has demonstrated the ability for disease modification and symptom reversal: worldwide efforts are now underway to develop therapeutic strategies (including gene therapy) to treat and potentially cure CDD. While there are four active clinical trials, none assesses the full spectrum of this DEE to address true disease modification. While capability for disease modifying therapies is accelerating, there is a critical barrier for clinical trial readiness that may result in failure of these therapies, not due to lack of efficacy but due to lack of validated outcome measures.

CDD has been associated historically with Rett syndrome but there are many clear distinctions and CDD has emerged as an independent disorder. Some Clinical Outcome Measures (COMs) can be adapted from Rett syndrome COMs, whereas others need to be developed specifically for CDD. Our research network is uniquely positioned to develop clinical trial readiness for CDD by pairing exceptional experience in the development and validation of outcome measures with an extensive network of CDD experts and clinical trialists. Our goals are to 1) refine and validate appropriate quantitative COMs and biomarkers and 2) conduct a multi-site clinical trial readiness study to ensure that they can be successfully implemented. We will test the hypothesis that CDD specific COMs can be refined to accurately and reproducibly track meaningful changes in clinical trials:

Aim 1: Generate and validate a suite of COMs and biomarkers necessary to comprehensively assess disease modification in CDD.

Aim 2: Conduct a multi-site clinical trial readiness study to assess implementation, longitudinal stability, and collect baseline COMs and EEG/evoked potential data.

Overall Impact: These outcome measures will establish clinical trial readiness for CDD and generate historic baseline outcome data, ensuring optimal testing of potential new therapeutics including gene therapy. Furthermore, these measures will be adaptable to other DEEs by enabling choices of outcome measures beyond existing NINDS supported measurement tools (NeuroQoL, PROMIS, Toolbox) that are not designed for the severity of the DEE populations.

02

Conditions studied

  • CDKL5
  • CDKL5 Deficiency Disorder
  • CDD
03

In context

Lead sponsor

University of Colorado, Denver is the lead sponsor of 1,538 studies on the registry; 318 are open to participants now.

Of its 146 completed or terminated interventional studies of FDA-regulated products, 92 (63%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
1 Month to 100 Years
Sexes eligible
All
Accepts healthy volunteers
No
Sampling method
Probability sample

Study population

Patients with CDKL5 Deficiency Disorder (CDD).

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • All children diagnosed with CDD age 1-month to 100 years of age that are receiving care at one of the study institutions or are registered with the International CDKL5 Disorder Database will be considered for the study population.

Exclusion criteria

Exclusion Criteria:

  • Individuals who do not meet study inclusion criteria.
05

Study design

Observational model
Cohort
Time perspective
Prospective
Enrollment
1,000 participants (estimated)
Patient registry
No

Interventions

  • OtherNo intervention.

    No intervention administered as part of this study; observational only.

06

What researchers measure

Primary outcomes

  1. CDKL5 Deficiency Disorder (CDD) Clinical Severity Assessment - Clinician (CCSA-Clinician)

    Measured by clinician rating of patient. Item scores are transformed to a scale of 0-100 and the total score is calculated as a mean item score. Higher scores indicate higher severity.

    Time frame: 5 years

  2. CDKL5 Deficiency Disorder (CDD) Clinical Severity Assessment - Caregiver (CCSA-Caregiver)

    Measured by caregiver/parent rating of patient on a scale of 0-100 with a higher score indicating higher severity.

    Time frame: 5 years

  3. CDKL5 Deficiency Disorder (CDD) Development Questionnaire - Caregiver (CDQ-Caregiver)

    Measured by caregiver/parent rating of patient on a scale of 0-100 with a higher score indicating higher severity.

    Time frame: 5 years

  4. Communication and Symbolic Behavior Scales - Developmental Profile Infant Toddler Checklist (CSBS-DP ITC)

    Measured by caregiver/parent rating of patient on a 24-item questionnaire. Three composite scores and a total score can be derived. Items contribute to the 0-57 point scale for the total score with lower scores indicating concerns for communication skills.

    Time frame: 5 years

  5. Sleep Disorder Scale for Children (SDSC)

    Measured by caregiver/parent rating of patient on a 26- Likert type item questionnaire. Scale goes from 0-39 with a higher score indicating higher severity of sleep disorder. Each subscale is scored through the summation of all the subscale items. Comparing scores were the normative data reported in the initial validation paper, z-scores and t-scores can be derived. The t-score enables scores to be dichotomized as within normal range or outside of normal range, compared to the general population.

    Time frame: 5 years

  6. Quality of Life Inventory - Disability (QI-Disability)

    This is a quality of life measure for children with intellectual disability. The measure comprises 32 items that are rated on a five-point Likert scale and group into six subscales: physical health, positive emotions, negative emotions, social interactions, independence, and leisure and outdoors. Following transformation to a 100-point scale, item scores in each subscale are summed and divided by the number of items to give a subscale score. The mean of the six subscale scores is calculated to give the total QOL score.

    Time frame: 5 years

  7. CDKL5 Deficiency Disorder (CDD) Gross Motor (CDD-Motor)

    This is a video measure of gross motor function, based on the Rett Syndrome Gross Motor Scale with additional items that enable measurement of head control and sitting. Parents are provided with a filming protocol, video clips are uploaded to the investigators, and data are coded according to a predetermined coding system.

    Time frame: 5 years

  8. CDKL5 Deficiency Disorder (CDD) Fine Motor (CDD-Hand)

    This is a video measure of fine motor function based on the Rett Syndrome Hand Function Scale with additional instructions on filming for if the patient has Cortical Visual Impairment. Parents are provided with a filming protocol, video clips are uploaded to the investigators, and data are coded according to a predetermined coding system.

    Time frame: 5 years

  9. Electroencephalogram/Evoked Potentials (EEG/EP) characteristics in CDKL5 Deficiency Disorder.

    Measured by correlations of EEG/EP with other study scales.

    Time frame: 5 years

Secondary outcomes

  1. Frequency of different mutations in the CDKL5 Deficiency Disorder population

    Measured by information obtained from genetic reports of enrolled participants.

    Time frame: 5 years

  2. Frequency of medications and their indications in the CDKL5 Deficiency Disorder population

    Measured by medication/indication data obtained from medical record review and/or caregiver report.

    Time frame: 5 years

  3. Social Determinants of Health (SDOH) in CDKL5 Deficiency Disorder population

    Measured by data elements that are collected to describe the socioeconomic status of the study population. Examples include caregiver education level, marital status and employment status, patient living situation, household income, and primary caregiver information.

    Time frame: 5 years

07

Study locations

9 of 9 sites recruiting
  • University of California Los Angeles/UCLA Mattel Children's Hospital
    Los Angeles, California 90095, United States
    Recruiting
  • University of Colorado Denver/Children's Hospital Colorado
    Aurora, Colorado 80045, United States
    Recruiting
  • Harvard Medical School/Boston Children's Hospital
    Boston, Massachusetts 02115, United States
    Recruiting
  • Washington University in St. Louis/St. Louis Children's Hospital
    St Louis, Missouri 63110, United States
    Recruiting
  • NYU Langone Health
    New York, New York 10016, United States
    Recruiting
  • Cleveland Clinic Foundation
    Cleveland, Ohio 44195, United States
    Recruiting
  • Children's Hospital of Philadelphia
    Philadelphia, Pennsylvania 19104, United States
    • Holly Dubbs · Contact · mdubbsh@chop.edu
    • Eric Marsh, MD PhD · Principal investigator
    • Erin Prange, MSN CRNP · Sub investigator
    Recruiting
  • Baylor College of Medicine/ Texas Children's Hospital
    Houston, Texas 77030, United States
    Recruiting
  • Telethon Kids Institute/Perth Children's Hospital
    Perth, Nedlands Western Australia 6009, Australia
    Recruiting
08

References and documents

Publications

  • Olson HE, Daniels CI, Haviland I, Swanson LC, Greene CA, Denny AMM, Demarest ST, Pestana-Knight E, Zhang X, Moosa AN, Fidell A, Weisenberg JL, Suter B, Fu C, Neul JL, Percy AK, Marsh ED, Benke TA, Poduri A. Current neurologic treatment and emerging therapies in CDKL5 deficiency disorder. J Neurodev Disord. 2021 Sep 16;13(1):40. doi: 10.1186/s11689-021-09384-z. PubMed 34530725 ↗
  • Brock D, Fidell A, Thomas J, Juarez-Colunga E, Benke TA, Demarest S. Cerebral Visual Impairment in CDKL5 Deficiency Disorder Correlates With Developmental Achievement. J Child Neurol. 2021 Oct;36(11):974-980. doi: 10.1177/08830738211019284. PubMed 34547934 ↗
  • Saldaris J, Weisenberg J, Pestana-Knight E, Marsh ED, Suter B, Rajaraman R, Heidary G, Olson HE, Devinsky O, Price D, Jacoby P, Leonard H, Benke TA, Demarest S, Downs J. Content Validation of Clinician-Reported Items for a Severity Measure for CDKL5 Deficiency Disorder. J Child Neurol. 2021 Oct;36(11):998-1006. doi: 10.1177/08830738211019576. Epub 2021 Aug 11. PubMed 34378447 ↗
  • Olson HE, Costantini JG, Swanson LC, Kaufmann WE, Benke TA, Fulton AB, Hansen R, Poduri A, Heidary G. Cerebral visual impairment in CDKL5 deficiency disorder: vision as an outcome measure. Dev Med Child Neurol. 2021 Nov;63(11):1308-1315. doi: 10.1111/dmcn.14908. Epub 2021 May 24. PubMed 34028805 ↗
  • MacKay CI, Bick D, Prokop JW, Munoz I, Rouse J, Downs J, Leonard H. Expanding the phenotype of the CDKL5 deficiency disorder: Are seizures mandatory? Am J Med Genet A. 2020 May;182(5):1217-1222. doi: 10.1002/ajmg.a.61504. Epub 2020 Feb 8. PubMed 32034940 ↗
  • Dale T, Downs J, Wong K, Leonard H. The perceived effects of cannabis products in the management of seizures in CDKL5 Deficiency Disorder. Epilepsy Behav. 2021 Sep;122:108152. doi: 10.1016/j.yebeh.2021.108152. Epub 2021 Jun 18. PubMed 34148781 ↗
  • Leonard H, Junaid M, Wong K, Demarest S, Downs J. Exploring quality of life in individuals with a severe developmental and epileptic encephalopathy, CDKL5 Deficiency Disorder. Epilepsy Res. 2021 Jan;169:106521. doi: 10.1016/j.eplepsyres.2020.106521. Epub 2020 Dec 1. PubMed 33341033 ↗
  • MacKay CI, Wong K, Demarest ST, Benke TA, Downs J, Leonard H. Exploring genotype-phenotype relationships in the CDKL5 deficiency disorder using an international dataset. Clin Genet. 2021 Jan;99(1):157-165. doi: 10.1111/cge.13862. Epub 2020 Oct 20. PubMed 33047306 ↗
  • Benke TA, Kind PC. Proof-of-concept for a gene replacement approach to CDKL5 deficiency disorder. Brain. 2020 Mar 1;143(3):716-718. doi: 10.1093/brain/awaa055. PubMed 32203572 ↗

Individual participant data

Plan to share: Yes — The ICCRN will be utilizing the National Institute of Mental Health (NIMH) Data Archive (NDA), previously known as the National Database for Autism Research (NDAR), as our final deidentified repository of our data. We will utilize Global Unique Identifiers to ensure we have deconflicted patient data across all institutions. Each institution will be directly uploading patient data to our central REDCap database to allow for cleaning of data prior to upload to NDA. Our data elements will be harmonized with other NDA elements where appropriate at the start of the study. The one exception is patient videos which will be reviewed at Telethon kids secure network for analysis, but the scored results of validated motor scales will be uploaded to NDAR in a deidentified fashion. All scales, outcome measures, and protocols (both for scoring and implementation of COMs) will also be shared through publications.

Supporting information: Study protocol, Statistical analysis plan, Informed consent form

Time frame: Available data will be released to the repository and will become available to the scientific community one year after publication of planned analyses, or after a period of 5 years from the date when the data were collected, whichever comes first.

Access criteria: NIMH NDA policy will govern access criteria.

Data sharing details ↗ · nda.nih.gov

09

Timeline

Tracking since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reached

Started Feb 2021 (actual). Primary completion is estimated for Feb 2026, 60 months after the start.

How these figures are worked out, and which studies are left out of them.

Registered
Jul 28, 2022
First posted
Sep 28, 2022
StartActual
Feb 15, 2021
Primary completionEst.
Feb 15, 2026
CompletionEst.
Feb 15, 2027
Last update
Dec 6, 2023
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
No changes since tracking began. The registry record was last updated on Dec 6, 2023, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT05558371
Responsible party
Sponsor
First posted
Sep 28, 2022
Start date
Feb 15, 2021
Primary completion
Feb 15, 2026 (estimated)
Completion
Feb 15, 2027 (estimated)
Last update
Dec 6, 2023

Study contacts

Sharon R Pincus, MA
Contact
sharon.pincus@cuanschutz.edu
303-949-7116
Scott T Demarest, MD MSCS
Contact
iccrn@childrenscolorado.org
Timothy A Benke, MD PhD
principal investigator · University of Colorado, Denver

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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