CDKL5 Gene and CDKL5 Deficiency Disorder: Clinical Trials

The CDKL5 gene sits on chromosome Xp22.13, and its full name is cyclin dependent kinase like 5. Orphanet links CDKL5 to 4 rare conditions and lists variants in the gene as a cause of all of them. Trial Friend's CDKL5 Deficiency Disorder page lists CDKL5 among the genes behind the condition. As of September 29, 2026, 6 recruiting or soon-opening trials on ClinicalTrials.gov name CDKL5 as a gene.

Other symbols for CDKL5 in gene databases: CFAP247, EIEE2.

See the trialsSearch another gene

What the CDKL5 gene does

CDKL5 makes a kinase, an enzyme that switches other proteins on or off. It is most active in the brain and is essential for normal brain development, including how nerve cells form, grow, move and signal to each other.

Summarized from the CDKL5 page on MedlinePlus Genetics, U.S. National Library of Medicine, checked September 29, 2026.

CDKL5 and CDKL5 Deficiency Disorder

These condition pages list CDKL5 among the genes behind the condition, checked against genetics references when each page was written.

CDKL5 Deficiency Disorder

The gene is on the X chromosome, and one variant can cause the condition in males or females.

Almost all cases are de novo CDKL5 variants; both sexes are affected, with severity in females influenced by X-inactivation.

CDKL5 mutation clinical trials

These recruiting or soon-opening trials mention CDKL5 as a gene in their title, summary, eligibility rules or keywords. Some want people with a variant in it, and others study it more broadly, which is why each trial's own words are shown. In cancer trials the gene change is usually one found in the tumor rather than one a person inherited.

6 trials, checked September 29, 2026. The list refreshes from ClinicalTrials.gov every few hours.

RecruitingNCT06585605
A Retrospective Survey-based Multicenter Study to Delineate the Molecular and Phenotypic Spectrum of Epilepsy-dyskinesia Syndromes
Epilepsy in Children · Dyskinesias · Movement Disorders in Children
Why it's listed: Lists CDKL5 among its conditions or keywords
RecruitingNCT05558371
International CDKL5 Clinical Research Network
CDKL5 · CDKL5 Deficiency Disorder · CDD
Why it's listed: “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 a…”
RecruitingNCT06967727
Registry and Natural History of Epilepsy-Dyskinesia Syndromes
Epilepsy-Dyskinesia · Epilepsy · Dyskinesia
Why it's listed: Lists CDKL5 among its conditions or keywords
Opening soonPhase 2NCT07635862
Clinical Trial Evaluating the Effects of Ganaxolone in Children With Autism
Autism in Children · Autistic Disorder in Children and Adolescents · Autism Spectrum Disorder
Why it's listed: “…approved and effective for treating seizures in children as young as 2 years old who have CDKL5 deficiency disorder (CDD), a neurogenetic condition associated with developmental delays, seizure di…”
Opening soonPhase 3NCT05249556
Double-blind, Randomized, Placebo-controlled Trial of Ganaxolone in CDKL5 Deficiency Patients 6 Months to Less Than 2 Years Old
CDKL5 Deficiency Disorder
Why it's listed: “…A diagnosis of CDD, including molecular confirmation of a pathogenic or likely pathogenic CDKL5 variant and refractory seizures (see Inclusion criterion 5).”
Opening soonNCT07602205
Efficacy and Safety of Daily Home-based Hyperthermic Baths for Reducing Epileptic Seizures in CDKL5 Deficiency Disorder: A PROBE Clinical Trial
CDKL5 Deficiency Disorder
Why it's listed: “A diagnosis of CDKL5 deficiency disorder, including molecular confirmation of a pathogenic CDKL5 variant and exhibiting e…”

All conditions linked to CDKL5 gene mutations

Orphanet records how each gene relates to each condition. Orphanet links CDKL5 to 4 rare conditions and lists variants in the gene as a cause of all of them.

  • Causes it. Disease-causing variants in this gene are a direct cause of the condition.
Atypical Rett syndromeCauses itTrial Friend pageOrphanet
CDKL5-deficiency disorderCauses itTrial Friend pageOrphanet
Early infantile developmental and epileptic encephalopathyCauses itOrphanet
Infantile epileptic spasms syndromeCauses itOrphanet

CDKL5 genetic test results and what a variant can mean

Labs sort each variant they find into 5 groups, from pathogenic and likely pathogenic through uncertain significance to likely benign and benign. Only the first 2 are usually treated as the cause of a condition. A variant of uncertain significance, or VUS, is one without enough evidence either way yet, and labs can reclassify it as research builds.

A genetic counselor or your doctor can explain what a specific result means for you and your family. Our genetic testing guide covers the terms, and MedlinePlus Genetics from the National Library of Medicine has a plain-language page on CDKL5.

CDKL5 gene questions

What does the CDKL5 gene do?

CDKL5 makes a kinase, an enzyme that switches other proteins on or off. It is most active in the brain and is essential for normal brain development, including how nerve cells form, grow, move and signal to each other. This summary follows MedlinePlus Genetics from the U.S. National Library of Medicine.

Are there clinical trials for people with CDKL5 gene variants?

As of September 29, 2026, 6 recruiting or soon-opening trials on ClinicalTrials.gov name CDKL5 as a gene. Each one is listed on this page with the words from the trial that mention the gene. ClinicalTrials.gov also lists 5 open trials for CDKL5 Deficiency Disorder, and Match Me on Trial Friend can check those against age, sex, location and treatment history.

What conditions are linked to the CDKL5 gene?

Orphanet links CDKL5 to 4 rare conditions and lists variants in the gene as a cause of all of them. They include Atypical Rett syndrome, CDKL5-deficiency disorder, Early infantile developmental and epileptic encephalopathy and Infantile epileptic spasms syndrome. Orphanet is the European rare disease database run by INSERM in Paris.

How is CDKL5 Deficiency Disorder inherited?

The inheritance pattern is X-linked dominant. The gene is on the X chromosome, and one variant can cause the condition in males or females. Almost all cases are de novo CDKL5 variants; both sexes are affected, with severity in females influenced by X-inactivation.

What does a CDKL5 variant of uncertain significance mean?

A variant of uncertain significance, or VUS, is a change in the gene that labs don't yet have enough evidence to call disease-causing or harmless. It is not used on its own to diagnose a condition, and labs can reclassify it as research builds. A genetic counselor can explain what a specific result means for you and your family.

Sources

  • Gene and condition links from Orphadata (Orphanet, INSERM US14), used under CC BY 4.0, read September 29, 2026.
  • Trials from ClinicalTrials.gov, read September 29, 2026.
  • CDKL5 gene, MedlinePlus Genetics, U.S. National Library of Medicine.
  • Inheritance and gene notes from the Trial Friend condition pages above, each checked against genetics references.

Other gene pages

The gene search covers every gene Orphanet links to a rare disease.