The primary objective of this research is to study the efficacy and safety of hyperthermic baths as adjunctive therapy for reducing the frequency of seizures in CDKL5 deficiency.

This project aims to include 8 participants, and evaluate the effectiveness and safety of hyperthermic baths in patients with CDKL5 deficiency through A single-center, preliminary feasibility clinical trial. It is expected to provide new therapeutic options for patients with CDKL5 deficiency with alternative treatment options.

Inclusion Criteria:

• A diagnosis of CDKL5 deficiency, including molecular confirmation of a pathogenic or likely pathogenic CDKL5 variant and refractory seizures
• Male or female participants aged 6 months to less than 6 years
• Parent(s) or LAR willing to give written informed consent, after being properly informed of the nature and risks of the study and prior to engaging in any study-related procedures
• Failure to control seizures despite appropriate trial of 2 or more anti-seizure medications at therapeutic doses
• Have a history of at least 8 countable seizures per 4 weeks during the 8 weeks prior to screening. Countable seizures will be defined by the following:Seizures with or without impairment of consciousness with a clear motor component, including generalized tonic-clonic, focal to bilateral tonic-clonic, atonic, bilateral clonic, bilateral tonic, focal motor seizures with or without impaired awareness, or infantile spasms. Clusters of infantile spasms/tonic seizures will be counted as a single seizure.
• Participants should be on a stable regimen of anti-seizure medications for ≥ 4 weeks prior to the screening visit, without a foreseeable change in dosing for the duration of the DB phase.
• Vagus nerve stimulator (VNS) are permitted, but should be implanted for 1 year prior to screening and settings should be unchanged throughout the study.
• Parent/caregiver is able and willing to maintain an accurate and complete daily seizure eDiary for the duration of the study.

Exclusion Criteria:

• Any history of previous brain disease (trauma, etc.) that likely to precipitate seizures.
• Tissue damage (eczema, etc.) in the area where hyperthermic baths will be applied on the skin.
• Seizures associated with hyperthermic baths.
• Presence of any clinical condition that in the opinion of the principal investigator makes the patient not suitable to participate in the trial.