for people ages 2-55 (full criteria)
study started
estimated completion



The purpose of this study is to investigate the effect of TAK-935 on the frequency of motor seizures for participants with 15q duplication syndrome or CDKL5 deficiency disorder during the Maintenance Period.

Official Title

A Multicenter, Open-label, Pilot Study of TAK-935 (OV935) in Patients With 15Q Duplication Syndrome or CDKL5 Deficiency Disorder (ARCADE Study)


The drug being tested in this study is called TAK-935 (OV935). TAK-935 is being tested to treat people with 15q duplication syndrome or CDKL5 deficiency disorder. This study will assess the effects of TAK-935 on seizure frequency, safety.

The study will enroll approximately 30 participants. Participants will be enrolled into 2 groups based on their diagnosis as: 15q duplication syndrome or CDKL5 deficiency disorder.

All participants will be asked to take TAK-935 tablets twice daily with or without food.

The study comprises of 2 periods: Screening/Baseline Period and Treatment Period (Dose Optimization and Maintenance). The overall time to participate in this study approximately 30 weeks, including 4 to 6 weeks Screening/Baseline Period, 20 weeks Treatment Period, 2 weeks Taper, and 2 weeks safety follow up period. Participants completing this study will have an option to enroll in the open-label extension (OLE) study, under a separate protocol.


15q Duplication Syndrome CDKL5 Deficiency Disease Drug Therapy Brain Diseases Epilepsy Central Nervous System Diseases Autism Infantile spams Cholesterol 24S-hydroxylase inhibitor Anti-epilepsy drug Anticonvulsants Cyclin-dependent kinase-like 5 deficiency disorder RETT syndrome Chromosome 15q Deficiency Diseases Syndrome TAK-935 TAK-935 (OV935)


You can join if…

Open to people ages 2-55

  1. Clinical diagnosis of 15q duplication syndrome or CDKL5 deficiency disorder
  2. Currently taking 1 to 6 antiepileptic drugs (AEDs) at a stable dose

You CAN'T join if...

  1. Two or more episodes of convulsive status epilepticus per 3 months requiring hospitalization and intubation
  2. Currently receiving a study drug or participated in a clinical study involving another investigational product in the previous month


  • UCLA accepting new patients
    Los Angeles California 90095 United States
  • Research Institute Children's Hospital Colorado accepting new patients
    Aurora Colorado 80045 United States


accepting new patients
Start Date
Completion Date
Phase 2
Study Type
Last Updated