Abstracts

Rationale: Cenobamate is approved in the US for treatment of focal seizures in adults. Here we describe the effectiveness and safety of adjunctive cenobamate treatment during routine clinical practice in patients with uncontrolled focal seizures who were living in a group home or living with a developmental disability.

Methods: Adults 18 years or older with uncontrolled focal seizures receiving treatment in routine clinical practice and on stable doses of 2 or more antiseizure medications (ASMs) were included. Effectiveness and safety data were collected retrospectively from medical records and patient seizure diaries. Effectiveness was examined as the percentage of patients achieving the responder rates of ≥50%, ≥75%, ≥90%, and 100% reduction in seizure frequency at months 5 and 6 of adjunctive cenobamate treatment. Safety was evaluated through report of side effects (SE). Down-dosing of concomitant ASMs following initiation of cenobamate was examined.

Results: The 28 patients (16 male/12 female) had a mean age of 38.4 years (range 19 to 64 years) and mean epilepsy duration of 34.9 years (range 15 to 62 years) at the start of cenobamate treatment. On average, patients had previously experienced treatment failure with 3.4 ASMs, and 53.6% of patients were receiving ≥4 ASMs at the start of cenobamate treatment. Mean seizure frequency in the 2-3 months before starting cenobamate was 20.9 seizures per month (median = 3.5). Reported seizures included focal impaired awareness (n=11), focal aware motor (n=2), and focal to bilateral tonic-clonic (FBTC) (n=16; 1 patient had both focal impaired awareness and FBTC seizures). Responder rates of ≥50%, ≥75%, ≥90%, and 100% seizure reduction occurred in 92.6%, 81.5%, 55.6%, and 48.2% of all patients with seizure data both pre- and post-treatment with cenobamate. Seizure reduction is shown in Figures 1 and 2. Mean cenobamate dose at 6 months was 156.7 mg/day (range 50-300 mg/day). SE were reported by 11 patients (39.3%): dizziness (4 patients; 3 resolved with lowered lacosamide); drowsiness (3; all resolved with lowered brivaracetam, clobazam, or clonazepam); ataxia (2; 1 resolved with lowered clobazam); and acting out (1; resolved with lowered clobazam). Two patients discontinued cenobamate prior to month 5 due to dizziness and ataxia SE, respectively. Dose reductions were most common with lacosamide (10 patients; median reduction = -47.0%), clobazam (5 patients; -100.0%), lamotrigine (4 patients; -43.8%), and perampanel (3 patients; all -100%).

Conclusions: During routine clinical practice for the treatment of uncontrolled focal seizures in patients living in a group home or living with developmental disability, substantial reduction in seizure frequency and high responder rates, including seizure freedom, occurred with adjunctive cenobamate. Treatment was well tolerated and SE were often mitigated or resolved following reduction of concomitant ASMs.

Funding: Please list any funding that was received in support of this abstract.: Medical writing support funded by SK Life Science, Inc.