Faculty Bibliography

From August 27-28, 2020 the Epilepsy Foundation hosted the Pipeline Conference, exploring emerging issues related to antiepileptic drug and device development. The conference featured epilepsy therapeutic companies and academic laboratories developing drugs for focal epilepsies, innovations for rare and ultra-rare diseases, and devices both in clinical trials and approved for use. In this paper, we outline the virtual presentations by the authors, including novel data from their development pipeline.

The COVID-19 pandemic has had an unprecedented impact on people and healthcare services. The disruption to chronic illnesses, such as epilepsy, may relate to several factors ranging from direct infection to secondary effects from healthcare reorganization and social distancing measures.

Importance/UNASSIGNED:Most antiseizure medications (ASMs) carry a US Food and Drug Administration-mandated class label warning of increased suicidality risk, based on a meta-analysis comparing suicidality between individuals treated with medications vs placebo in randomized clinical trials done before 2008. ASMs approved since then carry this warning although they were not similarly studied. Objective/UNASSIGNED:To review all placebo-controlled phase 2 and 3 studies of 10 ASMs approved since 2008 to evaluate the risk of suicidality of these drugs compared with placebo. Data Sources/UNASSIGNED:Primary publications and secondary safety analyses in PubMed of all phase 2 and 3 randomized placebo-controlled epilepsy trials of ASMs approved since 2008, using keywords epilepsy, antiepileptic drugs, seizures, suicidality, suicidal ideation, and the names of individual drugs. Study Selection/UNASSIGNED:All phase 2 and 3 randomized clinical trials of adjunctive treatment of drug-resistant epilepsy and their secondary safety analyses. Data Extraction and Synthesis/UNASSIGNED:Articles were reviewed for frequency of suicidality (ideation, attempts, and completed suicides). Mode of suicidality ascertainment included treatment-emergent adverse event reports, Standardized Medical Dictionary for Regulatory Activities queries for events in prespecified categories including suicidal ideation and behavior, prospective collection of suicidality data as a prespecified safety outcome using the Columbia-Suicide Severity Rating Scale, and retrospective evaluation by blinded review using the Columbia-Classification Algorithm of Suicide Assessment. A meta-analysis compared risk for drugs vs placebo of each outcome for all drugs overall and by individual drugs and trials. Main Outcomes and Measures/UNASSIGNED:Suicidality (total and by ideation), attempts, and completed suicides. Results/UNASSIGNED:Excluding studies that did not evaluate suicidality (everolimus and fenfluramine) or did not evaluate it prospectively (lacosamide, ezogabine, and clobazam), 5 drugs were analyzed: eslicarbazepine, perampanel, brivaracetam, cannabidiol, and cenobamate. Suicidality was evaluated in 17 randomized clinical trials of these drugs, involving 5996 patients, of whom 4000 patients were treated with ASMs and 1996 with placebo. There was no evidence of increased risk of suicidal ideation (drugs vs placebo overall risk ratio, 0.75; 95% CI, 0.35-1.60) or attempt (risk ratio, 0.75; 95% CI, 0.30-1.87) overall or for any individual drug. Suicidal ideation occurred in 12 of 4000 patients treated with ASMs (0.30%) vs 7 of 1996 patients treated with placebo (0.35%) (P = .74). Three patients treated with ASMs and no patients treated with placebo attempted suicide (P = .22). There were no completed suicides. Conclusions and Relevance/UNASSIGNED:There is no current evidence that the 5 ASMs evaluated in this study increase suicidality in epilepsy and merit a suicidality class warning.

OBJECTIVE:This study was undertaken to examine long-term (up to 7.8 years) retention rate, safety, and tolerability of the antiseizure medication (ASM) cenobamate as adjunctive treatment in the open-label extension (OLE) of study YKP3089C013 (C013; ClinicalTrials.gov: NCT01397968). METHODS:Patients who completed the 12-week, multicenter, multinational, double-blind, randomized, placebo-controlled C013 study, which examined adjunctive cenobamate treatment of adults with uncontrolled focal seizures, were eligible to enroll in the OLE. During the OLE, dose adjustments of cenobamate and concomitant ASMs were allowed. Safety assessments included frequency of treatment-emergent adverse events (TEAEs) and serious TEAEs, TEAE severity, and TEAEs leading to discontinuation. Probability of patient continuation in the OLE was examined using a Kaplan-Meier analysis. RESULTS:One hundred forty-nine patients entered the OLE (median duration of cenobamate treatment = 6.25 years). As of the data cutoff, 57% of patients (85/149) remained in the OLE (median treatment duration = 6.8 years, range = 6.4-7.8 years). The median modal daily cenobamate dose was 200 mg (range = 50-400 mg). The probability of treatment continuation at 1-6 years of cenobamate treatment was 73%, 67%, 63%, 61%, 60%, and 59%, respectively. Among patients who continued at 1 year (n = 107), the probability of continuing at Years 2-5 was 92%, 87%, 83%, and 82%. The most common discontinuation reasons were patient withdrawal (19.5%, 29/149), adverse event (10.1%, 15/149), and lack of efficacy (5.4%, 8/149). TEAEs leading to discontinuation in 1% or more of patients were fatigue (1.3%, 2/149), ataxia (1.3%, 2/149), and memory impairment or amnesia (1.3%, 2/149). Dizziness (32.9%, 49/149), headache (26.8%, 40/149), and somnolence (21.5%, 32/149) were the most frequently reported TEAEs and were primarily mild or moderate in severity. SIGNIFICANCE/CONCLUSIONS:Long-term retention in the C013 OLE study demonstrated sustained safety and tolerability of adjunctive cenobamate treatment up to 7.8 years in adults with treatment-resistant focal seizures taking one to three ASMs.

This is a summary report of clinical and regulatory issues discussed at the 2018 NINDS workshop, entitled "Accelerating Therapies for Antiepileptogenesis and Disease Modification". The intent of the workshop was to optimize and accelerate development of therapies for anti-epileptogenesis (AEG) and disease modification in the epilepsies. The working group discussed nomenclature for antiepileptogenic therapies, subdividing them into antiepileptogenic therapies" and "disease modifying therapies", both of which are urgently needed. We use the example of traumatic brain injury to explain issues and complexities in designing a trial for disease preventing antiepileptogenic therapies, including identifying timing of intervention, selecting the appropriate dose, and the need for biomarkers. We discuss the recent trials of vigabatrin to prevent onset and modify epilepsy outcome in children with tuberous sclerosis (Epistop and PreVeNT). We describe a potential approach to a disease modification trial in adults, using patients with Temporal Lobe Epilepsy. Finally, we discuss regulatory hurdles for antiepileptogenesis and disease modifying trials.

OBJECTIVE:To analyze electronic diary (e-diary) use in a phase 2, randomized, controlled clinical trial (OPUS; NCT03283371) of natalizumab in adult participants with drug-resistant focal epilepsy. METHODS:We developed an e-diary, which incorporated an episodic seizure diary and a daily diary reminder, for use as the primary source to record participants' daily seizure activity in the OPUS phase 2 clinical trial. Participants and/or their designated caregivers made e-diary entries by selecting seizure descriptions generated in the participants' and/or caregivers' own words at the time of screening. Seizures and seizure-free days were reported for the current day and for up to 5 and 4 retrospective days, respectively. A record of seizure symptoms entered within the prior 5-day period was displayed on accessing the diary. Changes were not permitted in the e-diary once a seizure record was saved unless a data change request was made. A paper backup diary was available. RESULTS:E-diary entries (N = 15,176) from the 6-week baseline period and subsequent 24-week placebo-controlled period were analyzed for 66 adults who were randomized and dosed in the OPUS trial. The overall e-diary compliance, defined as the total number of days with any entry out of the total number of days in the baseline and placebo-controlled periods for all participants combined, was 83.6%. Caregivers made 190 (1.3%) e-diary entries. Day-of-event e-diary entries totaled 11,248 (74.1%). At least one paper backup diary was used by 36 (54.5%) participants. SIGNIFICANCE:Our data highlight that good e-diary compliance can be achieved across participants in randomized clinical trials in adult focal epilepsy. In addition to identifying and addressing any barriers that may prevent a minority of participants from achieving good e-diary compliance, consideration of e-diary elements, such as recall period and reporting of seizure-free days, will facilitate the most accurate data capture in epilepsy clinical trials.

OBJECTIVE:To evaluate the safety, tolerability, and pharmacokinetics of soticlestat, a first-in-class cholesterol 24-hydroxylase inhibitor, in adults with developmental and/or epileptic encephalopathies (DEE). METHODS:The study comprised a 30-day, randomized, double-blind, placebo-controlled phase (Part A), followed by a 55-day open-label phase (Part B) (ClinicalTrials.gov ID: NCT03166215) . In Part A, patients with DEE and at least one bilateral motor seizure during the 4-week prospective baseline period were randomized 4:1 to receive soticlestat or placebo, in addition to their usual antiseizure medication. In Part B, all patients received open-label soticlestat. Soticlestat doses were titrated according to tolerability to a maximum of 300 mg twice daily (BID). Safety evaluations included the incidence of treatment-emergent adverse events (TEAEs). Plasma soticlestat concentrations were measured at various times for determination of multiple-dose pharmacokinetics and 24S-hydroxycholesterol (24HC). Efficacy was assessed by evaluation of changes in seizure frequency from baseline. RESULTS:Eighteen patients (median age, 28.5 years) were enrolled and randomized, and 14 (78 %) completed the study. In Part A, TEAEs occurred in 71.4 % of soticlestat-treated patients and 100 % of placebo-treated patients. In Part B, the overall incidence of TEAEs was 68.8 %. In Part A, TEAEs that occurred in more than one patient in the soticlestat group were dysarthria (n = 3, 21.4 %), lethargy (n = 2, 14.3 %), upper respiratory tract infection (n = 2, 14.3 %), fatigue (n = 2, 14.3 %), and headache (n = 2, 14.3 %). Four patients discontinued treatment because of TEAEs, of whom two reported drug-related seizure clusters as serious TEAEs. There were no deaths. Pharmacokinetic analysis showed dose-dependent increases in systemic exposure and peak plasma soticlestat concentrations. At the end of Part B, the overall mean percent change from baseline in plasma 24HC was -80.97 %. Changes from baseline in median seizure frequency were +16.71 % and +22.16 % in the soticlestat and placebo groups, respectively, in Part A, and -36.38 % in all participants in Part B. CONCLUSION/CONCLUSIONS:Soticlestat was well tolerated at doses of up to 300 mg BID and was associated with a reduction in median seizure frequency over the study duration. Further studies are warranted to assess the possible efficacy of soticlestat as adjunctive therapy in patients with DEEs such as Dravet syndrome and Lennox-Gastaut syndrome.

OBJECTIVE:Many people with new-onset focal epilepsy initially seek evaluation in emergency departments (EDs), and treatment decisions in EDs can influence likelihood of seizure recurrence. Using data collected for the Human Epilepsy Project (HEP), we assessed the effect of clinical seizure characteristics on ED clinical management. METHODS:There were 447 participants with new-onset focal epilepsy seen within four months of treatment initiation who were eligible and enrolled in HEP. Seizure calendars and medical records were collected. Based on clinical descriptions, seizures were categorized by semiology according to International League Against Epilepsy (ILAE) classifications as either focal non-motor or focal motor seizures. RESULTS:Overall, 279/447(62%) of participants had presented to an ED prior to or at time of epilepsy diagnosis. 132 /246 (53%) with initial non-motor seizures presented to an ED. Of these, 8 (6%) presented with a first-lifetime non-motor seizure. The other 124 (94%) presented after multiple seizures: 7 (5%) with multiple non-motor seizures, and 117 (89%) with a first-lifetime motor seizure after having prior non-motor seizures. 147/ 201 (73%) of participants with initial motor seizures presented to an ED. Of these, 134 (92%) presented with a first-lifetime motor seizure, and 13 (9%) with multiple motor seizures. There was no difference in the likelihood of anti-seizure medication (ASM) initiation between participants who had multiple prior non-motor seizures followed by a motor seizure (thereby fulfilling the criterion for an epilepsy diagnosis), vs those presenting with a single lifetime motor seizure (39% vs 43%). There was no difference in recognition of seizures as the presenting complaint (85% vs 87%), or whether the participant was admitted or referred to a neurologist (87% vs 79%). CONCLUSIONS:This study contributes to evidence of under-recognition of non-motor focal seizure semiologies in ED settings, which can support large-scale interventions aimed at improving recognition, specialist consultation, and treatment in ED settings.

Literature review of patients with KCNQ2 developmental and epileptic encephalopathy (KCNQ2-DEE) reveals, based on 16 reports including 139 patients, a clinical phenotype that includes age- and disease-specific stereotyped seizures. The typical seizure type of KCNQ2-DEE, focal tonic, starts within 0-5 days of life and is readily captured by video-electroencephalography VEEG for clinical and genetic diagnosis. After initial identification, KCNQ2-DEE seizures are clinically apparent and can be clearly identified without the use of EEG or VEEG. Therefore, we propose that the 2019 recommendations from the International League against Epilepsy (ILAE), the Pediatric Epilepsy Research Consortium (PERC), for capturing and recording seizures for clinical trials (Epilepsia Open, 4, 2019, 537) are suitable for use in KCNQ2-DEE‒associated antiseizure medicine (ASM) treatment trials. The ILAE/PERC consensus guidance states that a caregiver-maintained seizure diary, completed by caregivers who are trained to recognize seizures using within-patient historical recordings, accurately captures seizures prospectively in a clinical trial. An alternative approach historically endorsed by the Food and Drug Administration (FDA) compares seizure counts captured on VEEG before and after treatment. A major advantage of the ILAE/PERC strategy is that it expands the numbers of eligible patients who meet inclusion criteria of clinical trials while maintaining accurate seizure counts (Epilepsia Open, 4, 2019, 537). Three recent phase 3 pivotal pediatric trials investigating ASMs to treat syndromic seizures in patients as young as 2 years of age (N Engl J Med, 17, 2017, 699; Lancet, 21, 2020, 2243; Lancet, 17, 2018, 1085); and ongoing phase 2 open-label pediatric clinical trial that includes pediatric epileptic syndromes as young as 1 month of age (Am J Med Genet A, 176, 2018, 773), have already used caregiver-maintained seizure diaries successfully. For determining the outcome of a KCNQ2-DEE ASM treatment trial, the use of a seizure diary to count seizures by trained observers is feasible because the seizures of KCNQ2-DEE are clinically apparent. This strategy is supported by successful precedent in clinical trials in similar age groups and has the endorsement of the international pediatric epilepsy community.