A new investigational therapy is offering hope for patients with CDKL5 deficiency disorder (CDD), a rare pediatric epilepsy. One in 40,000 to 60,000 newborns are affected by the disorder characterized by seizures and severe developmental disabilities.
Sarah Schreiber, a mother of three, started the CDD journey with her young daughter Charlotte. When Schreiber noticed her three-week-old daughter making unusual movements, she took a video and showed it to her daughter’s pediatrician, and then as steps progressed, to a neurologist. They all agreed something was wrong and conducted a battery of tests.
Once the doctors determined Charlotte’s CDD diagnosis at three months old, Schreiber realized her daughter would not only be inflicted by seizures, she would also face a lifetime of cognitive impairment.
Now, nearly two-and-a-half years old, Charlotte can stand with assistance and sit by herself, but she cannot walk. She has seizures every day, making her pale, lethargic, and fatigued. She often looks scared after her seizures and remains nonverbal and unable to communicate how she feels.
“She’s in a lot of therapy and she’s come a really long way from the beginning,” says Schreiber. “It’s been slow but it’s huge to us.”
New investigational treatments
Though there isn’t a specific medication that has been approved for CDD, companies have been fighting to get one to market. One such company is Pennsylvania-based Marinus Pharmaceuticals Inc., which in September 2020, showed a 32.2 percent reduction in seizure frequency with its investigational drug, in a pivotal Phase 3 clinical trial of 101 patients aged 2-21 diagnosed with the disorder.
“The hallmarks of CDD are the onset of early seizures and severe developmental delay, which impacts cognition, motor speech, and visual function for these children,” says Heidi Grabenstatter, Ph.D., science director at the International Foundation for CDKL5 Research.
She says children with this disorder have problems walking and difficulties with language and motor development. Although the disorder is most common in girls, more boys are being diagnosed with it as well.
“Medically, they’re fragile children,” she says. “And it’s a lifelong disorder — they’re going to require 24-hour care from their parents or caregivers. They can’t live independently.”
Scott Braunstein, M.D., CEO of Marinus Pharmaceuticals, says “we believe our Phase 3 trial showed meaningful clinical effect.” He is encouraged that many of the CDD patients in the trial who failed other therapies are continuing on the investigational treatment in an extension of the clinical trial.
The seizure reduction is important because when patients have seizures, they tend to regress. It’s “one step forward and two steps back,” says Dr. Braunstein. “The hope is that the earlier you treat, the more seizure activity you can minimize, and the more likely these children are to have incrementally less neurocognitive impairment and better overall outcomes.”
Medicines used to control seizures in these patients typically lose effectiveness over time. Patients with CDD often stop responding to treatments after three to six months, Dr. Braunstein added.
Dr. Grabenstatter says getting some control over seizures helps caregivers manage the daily living and care for children with CDD.
“Families never thought they’d see the day that there would be a drug that would be developed for CDKL5 deficiency disorder,” she says.
Marinus Pharmaceuticals plans to file a new drug application with the FDA and hopes to have the drug on the market by mid 2022. Marinus currently has an expanded access program to make it available at no charge to patients, if their doctor believes it will be beneficial.
Schreiber says her family is grateful for companies like Marinus that are researching CDD, with the potential to bring drugs to market for these patients.
Marinus Pharmaceuticals has a strong commitment to supporting patients with rare seizure disorders like Charlotte, and other patients and caregivers. The company shows this commitment through its significant research and development efforts in rare epilepsies.
To learn more about CDD, rare pediatric epilepsy, and treatment therapies being developed, visit https://www.cdkl5.com/.