AAN 2020 Clinical Trial Data: Uncontrolled Focal Seizures

Ian Miller, MD: The abstract being presented by Dr Pavel Klein and his coauthors regarding the use of cenobamate in patients with uncontrolled focal seizures was exciting because it showed sustained efficacy for very robust randomized clinical trial data that were originally presented. It also shows a modest adverse effect profile. The value or the number in the abstract that sticks out the most to me is the percentage of patients who continued with treatment past 24 months, and that number for the cenobamate study was 69.6%. That tells me that patients are getting enough value—in terms of seizure control—out of the medication that they’re willing to stay on it because whatever adverse effects they might have are modest enough that it’s worth taking the medication.

Other factors that are important of the cenobamate study are that it was performed in adults and it used different doses of 100 mg, 200 mg, and 400 mg daily. We have some sense of what the tolerability range of dosing is and the fact that all those doses were reasonably well tolerated and efficacious. The efficacy did seem like it got more robust with time, with the seizure reduction being 65% at the 6-month time point and going up to 76% over the 2- to 2½-year time frame. And that was made all the more remarkable by the fact that just over a fifth of the patients were actually seizure-free.

I was also excited to see a few forms of rescue medication. The 1 I was most excited about was the nasal diazepam, because it will be very comparable in terms of dosing to rectal diazepam, which a lot of my patients who are pediatric, graduate from. So if you have a younger child who has the diazepam rectal formulation for the abortive treatment of seizures, once they’re old enough that rectal treatment is a little socially problematic or too privacy invasive, they can be switched to the nasal formulation, which doesn’t have those problems, which is great.