DENVER — The conclusions were reached by comparing outcomes to patient historical data, though they were not analyzed statistically.
A Proof-of-Concept Study
In an interview, Karen Keough, MD, who presented the study during a poster session at the 2024 annual meeting of the American Academy of Neurology, conceded the key limitation was that the researchers were not able to perform statistical analysis due to the nature of the data. “It’s just showing trends. It’s proof of concept that cenobamate can be effective in one of the most refractory forms of epilepsy, which always includes focal seizures. That’s what led to the initial FDA indication, but we also know that this medication has a lot of promise and is probably going to be effective in other forms of epilepsy and probably in other seizure types,” said Dr. Keough, who is a neurologist at Pediatrix Child Neurology Consultants of Austin, Texas.
Although she has seen significant improvements in many patients, Dr. Keough reported that most patients become refractory again. “Unfortunately, honeymoons are probably real in cenobamate. Continuing to follow those patients as I do, since they’re my own patients, I have quite a few who had more than a year of seizure freedom, [but] their seizures are back, though not as bad as they were before cenobamate. I just can’t get them back to that 100% control category. I do have a few that are still in the 100% control category, but not very many,” she said.
She also presented a retrospective chart review of 36 LGS patients between the ages of 1 and 27 years at the American Epilepsy Society in December 2023, which showed that addition of cenobamate was associated with a reduction in seizure frequency in 85% of patients. “It was a profound number of patients who had long periods of seizure freedom,” she said.
A Promising Treatment Option
Dr. Keough is considering moving cenobamate up in the treatment sequence of new LGS patients. “I don’t use cenobamate first line in anyone because we have good first-line agents for simple epilepsy in Lennox-Gastaut, but I’m bringing out cenobamate pretty early in the course, because I do think it has superior efficacy compared with most other drugs that we have available. Most of my patients are very established and they’ve seen lots of other drugs. For many patients, there are only a couple of drugs left on the list that [they] have never tried, but we’re going to put cenobamate at the top of that. For my newer diagnoses, I’m going to bring it out much earlier,” she said, though other drugs such as clobazam (Onfi) would still rank ahead of cenobamate.
The study was drawn from records of the HealthVerity Marketplace Database, which includes more than 150 commercial, Medicare, and Medicaid payers. It included 76 patients aged 17 or under who took at least one antiseizure medication between May 2020 and December 2022, and who had filled at least two prescriptions of cenobamate and had 180 or more days of medical and pharmacy enrollment. The mean age was 13.4 years (5.3% 0-5 years, 15.8% 6-11 years, 78.9% 12-17 years), and 40.8% were female. Seizure types included absence (17.1%), focal (75.0%), and generalized tonic-clonic (86.8%). All patients had a history of intractable seizures, 80.3% had a history of status epilepticus, and 28.9% had a history of infantile seizures. A little more than one fourth (27.6%) of patients had commercial insurance. In the previous 90 days, 21.1% had had an emergency room visit or in-patient hospital stay.
Common antiseizure medications taken with cenobamate included cannabidiol (n = 14), clobazam (n = 8), and levetiracetam (n = 18).
During the cenobamate treatment period, patients had a lower incidence of epilepsy-related inpatient days per year (3.36 vs 3.94), epilepsy-related ER visits per year (0.66 vs 1.19), and likelihood of requiring a new line of epilepsy therapy (35.5% vs 100%).