for people ages 2-21 (full criteria)
study started
estimated completion



A clinical study to evaluate the efficacy, safety, and tolerability of adjunctive ganaxolone therapy compared to placebo for the treatment of seizures in children and young adults with genetically confirmed CDKL5 gene mutation.

Official Title

A Double-blind, Randomized, Placebo-controlled Trial of Adjunctive Ganaxolone Treatment in Children and Young Adults With Cyclin-dependent Kinase-like 5 (CDKL5) Deficiency Disorder (CDD) Followed by Long-term Open-label Treatment


The Marigold Study is a global, double-blind, placebo-controlled, Phase 3 clinical trial that will enroll approximately 70 patients between the ages of 2 and 21 with a confirmed disease-related CDKL5 gene variant. Patients will undergo a baseline period before being randomized to receive, in addition to their existing anti-seizure treatment, either ganaxolone or placebo for 17 weeks. Following the treatment period, all patients that meet certain eligibility requirements will have the opportunity to receive ganaxolone in the open label phase of the study. The study's primary efficacy endpoint is percent reduction in seizures. Secondary outcome measures will include non-seizure-related endpoints to capture certain behavioral and sleep disturbances that have been seen in previous clinical studies with ganaxolone.


CDKL5 Deficiency Disorder refractory seizures genetic pediatric encephalopathies epilepsy in children seizure disorder Disease Pregnanolone Ganaxolone


You can join if…

Open to people ages 2-21

  • Genetically confirmed CDKL5 gene mutation, seizure onset by 1 year of age and lack of independent ambulation by 2 years of age
  • Failure to control seizures despite 2 or more anti-seizure medications
  • At least 16 seizures per 28 days of primary seizure types
  • On a stable regimen of 0-4 anti-seizure medications (Vagus nerve stimulator, ketogenic diet, and modified Atkins diet do not count towards this limit)
  • Additional Inclusion Criteria apply and can be discussed with study team

You CAN'T join if...

  • Previous exposure to ganaxolone
  • West Syndrome with hypsarrhythmia pattern on EEG or seizures predominantly of Infantile Spasms type
  • Use of adrenocorticotropic hormone (ACTH), prednisone or other glucocorticoid or use of moderate or strong inducers or inhibitors of CYP3A4/5/7 are prohibited
  • Use of tetrahydrocannabinol (THC) or cannabidiol (CBD) is prohibited during the double-blind phase, unless patient has a prescription of Epidiolex®
  • Exposure to any other investigational drug within 30 days or fewer than 5 half-lives prior to screening
  • Plasma allopregnanolone-sulfate (Allo-S) levels greater than or equal to 6.0 ng/ml at screening visit
  • Additional Exclusion Criteria apply and can be discussed with study team


  • Marinus Research Site
    Los Angeles California 90095-1742 United States
  • Marinus Research Site
    Phoenix Arizona 85016 United States


in progress, not accepting new patients
Start Date
Completion Date
Marinus Pharmaceuticals
Phase 3
Study Type
Last Updated