Is Cenobamate the Breakthrough We Have Been Wishing for?

Effectiveness and Safety of Adjunctive Cenobamate in People with Focal-Onset Epilepsy: Evidence from the First Interim Analysis of the BLESS Study

INTRODUCTION

Despite new anti-seizure medications (ASMs) being introduced into clinical practice, about one-third of people with epilepsy do not reach seizure control. Cenobamate is a novel tetrazole-derived carbamate compound with a dual mechanism of action. In randomized controlled trials, adjunctive cenobamate reduced the frequency of focal seizures in people with uncontrolled epilepsy. Studies performed in real-world settings are useful to complement this evidence and better characterize the drug profile.

METHODS

The Italian BLESS ("Cenobamate in Adults With Focal-Onset Seizures") study is an observational cohort study aimed to evaluate the effectiveness, tolerability, and safety of adjunctive cenobamate in adults with uncontrolled focal epilepsy in the context of real-world clinical practice. The study is ongoing and conducted at 50 centers in Italy. This first interim analysis includes participants enrolled until June 2023 and with 12-week outcome data available.

RESULTS

Forty participants with a median age of 36.5 (interquartile range [IQR] 26.0-47.5) years were included. The median monthly seizure frequency at baseline was 6.0 (IQR 2.5-17.3) seizures and 31 (77.5%) participants had failed four or more ASMs before cenobamate. At 12 weeks from starting cenobamate, the median reduction in monthly seizure frequency was 52.8% (IQR 27.1-80.3%); 22 (55.0%) participants had a ≥ 50% reduction in baseline seizure frequency and six (15.0%) reached seizure freedom. The median number of concomitant ASMs decreased from 3 (IQR 2-3) at baseline to 2 (IQR 2-3) at 12 weeks and the proportion of patients treated with > 2 concomitant ASMs decreased from 52.5% to 40.0%. Seven (17.5%) patients reported a total of 12 adverse events, 11 of which were considered adverse drug reactions to cenobamate.

CONCLUSION

In adults with uncontrolled focal seizures, the treatment with adjunctive cenobamate was well tolerated and was associated with improved seizure control and a reduction of the burden of concomitant ASMs.

TRIAL REGISTRATION NUMBER

NCT05859854 (ClinicalTrials.gov Identifier).

Safety assessment of cenobamate: real-world adverse event analysis from the FAERS database

Objective

This study aims to analyze adverse drug events (ADEs) associated with cenobamate from the FAERS database, covering the third quarter of 2020 to the second quarter of 2023.

Methods

Data related to cenobamate-associated ADEs from the third quarter of 2020 to the second quarter of 2023 were collected. After standardizing the data, various signal quantification techniques, including ROR, MHRA, BCPNN, and MGPS, were employed for analysis.

Results

Among 2535 ADE reports where cenobamate was the primary suspected drug, 94 adverse reactions involving 11 different System Organ Class (SOC) categories were identified through the application of four signal quantification techniques. More specifically, neurological disorders and injuries resultant from complications are frequent adverse reactions associated with cenobamate.

Conclusion

Our research findings align with established results, affirming the favorable safety profile of cenobamate. Effective prevention of adverse reactions induced by cenobamate can be achieved through the establishment of efficient blood concentration monitoring and dose adjustments.

Add-on treatment with cenobamate is already effective at low doses in refractory focal epilepsy: A prospective observational study

OBJECTIVE

Cenobamate, a novel antiseizure medication with a dual mechanism of action, has been shown in pivotal trials to significantly improve seizure control in treatment-resistant focal epilepsy. We aimed to evaluate whether these promising results could be confirmed in a real-world setting with a follow-up period of up to 12 months.

METHODS

Patients from a tertiary epilepsy center who received cenobamate add-on between June 2021 and October 2023 were followed up prospectively at 3, 6, and 12 months after treatment initiation for assessment of seizure outcomes and treatment-related adverse events.

RESULTS

The clinical cohort included 112 adult patients with 30% nonlesional cases and a wide spectrum of epileptogenic lesions underlying refractory focal epilepsy. We observed a significant reduction in monthly seizure frequency of all seizure types already after 3 months of treatment at a median cenobamate dose of 100 mg/day. Forty-six percent of patients were responders with a ≥50% seizure reduction, 26% had a ≥75% seizure reduction, and 9% became seizure-free. Among the 74 patients with available follow-up of 12 months, the responder rates reached 55%, 35%, and 19% for ≥50%, ≥75%, and 100% seizure reduction, respectively. After 3 months of treatment, 38% of patients reported adverse effects, mainly (84%) mild to moderate in intensity. Adjustment of comedication allowed successful management of adverse effects in 32% of patients. At a group level, there was no correlation between the cenobamate daily dose and the incidence of adverse events.

SIGNIFICANCE

We found a clinically relevant response to cenobamate already at a low daily dose of 100 mg also in a patient cohort with a higher degree of drug resistance than in pivotal trials. Our prospectively collected data provide real-world evidence for high efficacy and good tolerability of the drug, although no standardized treatment protocol or comparison with a control group was applied.

Cenobamate as add-on therapy for drug resistant epilepsies: effectiveness, drug to drug interactions and neuropsychological impact. What have we learned from real word evidence?

Background: Cenobamate (CNB) is an anti-seizure medication (ASM) approved in 2021 in Europe for adjunctive treatment of focal-onset seizures in adults who were not adequately controlled with at least two previous ASMs. Methods: seizure outcome, treatment-emergent adverse events, neuropsychological profile, and blood levels of CNB and concomitant ASM were analyzed in a real world setting in two different Italian epilepsy centers in the context of CNB early access program. All patients performed a general cognitive evaluation, while 32 patients underwent the administration of a battery of neuropsychological tests at baseline and 6 months after CNB treatment. We performed CNB quantification in plasma in 31 patients at different doses in the range of 100-400 mg/day (65 measures). Results: we enrolled 54 patients with a median age of 27.9 years. The mean follow-up was 10.7 months. Most (91%) completed the efficacy analysis. At last follow-up visit, a 69.5% median seizure reduction was registered. Thirty-two patients (59.2%) had a ≥50% reduction of seizures that was ≥75% in 20 (42.0%) cases, whilst 10 (20.2%) patients were seizure-free. The most common adverse events were somnolence (53.1%), dizziness (28.1%) and diplopia (12.5%). The correlation between CNB dose and plasma concentration, revealed a significant linear correlation (r = 0.86, p < 0.0001), and there was a significant difference in mean plasma concentration/dose administered ratio (C/D ratio) between patients taking or not at least one inducer (0.10 ± 0.04 [(μg/mL)/(mg/day)]; n = 47 vs. 0.13 ± 0.05 [(μg/mL)/(mg/day)]; n = 18, p = 0.04). CNB dose was inversely correlated (r = -0.31, p = 0.02) to the C/D ratio of Carbamazepine blood levels. and positively correlated (r = 0.74, p < 0.0001) with an increased plasma concentration of the active Clobazam metabolite N-desmethylclobazam. General Anxiety Disorder-7 showed a significant improvement of score from baseline evaluation of 6.82 to follow-up 6 months evaluation of 4.53 (p = 0.03). Conclusion: In this real-world study, we registered a clinically meaningful reduction in seizure frequency after CNB administration in most patients along with a good tolerability profile. CNB treatment is correlate to a reduction in symptom severity of anxiety score. Plasma levels measurements confirm that CNB acts both as "victim" and as "perpetrator" of drug-drug interactions.

Cenobamate (YKP3089) and Drug-Resistant Epilepsy: A Review of the Literature

Cenobamate (CNB), ([(R)-1-(2-chlorophenyl)-2-(2H-tetrazol-2-yl)ethyl], is a novel tetrazole alkyl carbamate derivative. In November 2019, the Food and Drug Administration approved Xcopri®, marketed by SK Life Science Inc., (Paramus, NJ, USA) for adult focal seizures. The European Medicines Agency approved Ontozry® by Arvelle Therapeutics Netherlands B.V.(Amsterdam, The Neatherlands) in March 2021. Cenobamate is a medication that could potentially change the perspectives regarding the management and prognosis of refractory epilepsy. In this way, this study aims to review the literature on CNB's pharmacological properties, pharmacokinetics, efficacy, and safety. CNB is a highly effective drug in managing focal onset seizures, with more than twenty percent of individuals with drug-resistant epilepsy achieving seizure freedom. This finding is remarkable in the antiseizure medication literature. The mechanism of action of CNB is still poorly understood, but it is associated with transient and persistent sodium currents and GABAergic neurotransmission. In animal studies, CNB showed sustained efficacy and potency in the 6 Hz test regardless of the stimulus intensity. CNB was revealed to be the most cost-effective drug among different third-generation antiseizure medications. Also, CNB could have neuroprotective effects. However, there are still concerns regarding its potential for abuse and suicidality risk, which future studies should clearly assess, after which protocols should be changed. The major drawback of CNB therapy is the slow and complex titration and maintenance phases preventing the wide use of this new agent in clinical practice.

Use of cenobamate for the treatment of focal epilepsy: an Italian expert opinion paper

INTRODUCTION

Cenobamate is a new antiseizure medication (ASM) recently introduced in the USA for the treatment of adults with focal-onset seizures. In March 2021, the European Commission authorized its use for the adjunctive treatment of focal-onset seizures with or without secondary generalization (focal seizures with or without progression to bilateral tonic-clonic seizures, according to current ILAE terminology) in adults with epilepsy not adequately controlled despite the treatment with at least two ASMs.

AREAS COVERED

This review summarizes the mechanism of action, efficacy, and safety of Cenobamate. The authors provide their expert opinions on the use of this drug.

EXPERT OPINION

The aim of this paper is to report on the Italian preliminary experience with the use of cenobamate, focusing on treatment goals, optimal dosing and titration schedules, strategies to minimize adverse effects, and identification of suitable candidates for treatment. There was agreement that slow titration may improve tolerability, and that clinically significant benefit can be achieved in many patients at relatively low doses. A favorable response to relatively low doses of cenobamate could be an early predictor of ultimate responsiveness. Overall, cenobamate is a welcome new treatment for adults with focal seizures resistant to conventional ASMs.