Frequency Of Partial-onset Seizures Research Articles

Robot-Assisted Responsive Neurostimulator System Placement in Medically Intractable Epilepsy: Instrumentation and Technique.

The management of medically refractory epilepsy patients who are not surgical candidates has remained challenging. Closed loop-or responsive-neurostimulation (RNS) is now an established therapy for the treatment of epilepsy with specific indications. The RNS® system (NeuroPace Inc, Mountainview, California) has recently been shown to be effective in reducing the seizure frequency of partial onset seizures. The electrode design consists of either intracerebral depth electrodes or subdural strip electrodes, and stereotaxis is typically used to guide placement into the EZ. Details on the operative techniques used to place these electrodes have been lacking. To address the advantage of using a robotic-assisted technique to place depth electrodes for RNS® system placement compared to the typical frame-based or frameless stereotactic systems. We retrospectively reviewed our single center, technical operative experience with RNS® system placement using robotic assistance from 2014 to 2016 via chart review. Twelve patients underwent RNS® system placement using robotic assistance. Mean operative time was 121 min for a median of 2 depth electrodes with mean deviation from intended target of ∼3 mm in x, y, and z planes. Two patients developed wound infections, 1 of whom was reimplanted. Seizures were reduced by ∼40% at 2 yr, similar to the results seen in the open label portion of the pivotal RNS trial. Robotic-assisted stereotaxis can be used to provide a stable and accurate stereotactic platform for insertion of intracerebral RNS electrodes, representing a safe, efficient and accurate procedure.

Efficacy and safety of adjunctive lacosamide for the treatment of partial-onset seizures in Chinese and Japanese adults: A randomized, double-blind, placebo-controlled study

ObjectiveTo evaluate the efficacy and safety of adjunctive lacosamide treatment in Chinese and Japanese adults with uncontrolled focal (partial-onset) seizures (POS), with or without secondary generalization. MethodsA 24-week, randomized, double-blind, placebo-controlled study (EP0008; NCT01710657) was conducted in patients (aged 16–70 years) with uncontrolled POS and taking 1–3 concomitant antiepileptic drugs from 72 sites across China and Japan. Following an 8-week Baseline period, randomized patients received lacosamide 200mg/day (100mg twice daily), 400mg/day (200mg twice daily), or placebo for 4-week Titration and 12-week Maintenance periods. The primary efficacy variable was the change in POS frequency per 28days from Baseline to Maintenance. ResultsOverall, 692 patients were screened; 548 were randomized to placebo (n=184), lacosamide 200mg/day (n=183), or lacosamide 400mg/day (n=181); 485 (88.5%) completed the study. The median change (range) in POS frequency per 28days from Baseline to Maintenance was −3.33 (−754.3 to 165.2), −4.50 (−97.5 to 28.2), and −1.22 (−93.0 to 39.8) in the lacosamide 200mg/day, 400mg/day, and placebo groups, respectively. Significant percentage reductions in POS frequency over placebo per 28days from Baseline to Maintenance were observed for lacosamide 200mg/day (29.4% [95% CI 18.7–38.7%], p<0.001) and 400mg/day (39.6% [30.5–47.6%], p<0.001). Higher ≥50% and ≥75% responder and seizure freedom rates were observed in lacosamide-treated patients vs placebo. Treatment-emergent adverse events reported by ≥10% of all lacosamide-treated patients occurring at ≥2% difference compared with placebo were dizziness (25.9% vs 9.2%) and somnolence (10.2% vs 3.8%). Dose-proportional pharmacokinetics were consistent with earlier global pivotal trials. ConclusionsAdjunctive lacosamide (200 and 400mg/day) was efficacious in reducing POS frequency in Chinese and Japanese patients with a safety and tolerability profile consistent with the three global pivotal studies.

Long-term safety and sustained efficacy of USL255 (topiramate extended-release capsules) in patients with refractory partial-onset seizures.

The aim of this study was to evaluate long-term safety, efficacy, and quality of life (QOL) of ≤400-mg/day USL255, Qudexy® XR (topiramate) extended-release capsules, as adjunctive therapy for partial-onset seizures (POS) in adults. Patients who completed the 11-week double-blind treatment phase of the phase 3 PREVAIL study were eligible to enroll in this 1-year open-label extension (OLE) study (PREVAIL OLE). The primary objective was to evaluate the safety and tolerability of USL255 (including treatment-emergent adverse events [TEAEs]). The secondary objective was to assess seizure frequency in patients (e.g., median percent reduction from baseline in weekly POS frequency, responder rate [proportion of patients with ≥25%, ≥50%, ≥75%, or 100% reduction from baseline in POS frequency], and seizure-free intervals [proportion of patients who were seizure-free for 4, 12, 24, 36, or 48weeks]). Exploratory clinical-status endpoints included the Global Impression of Change (CGI-C) and Quality of Life in Epilepsy-Problems (QOLIE-31-P) questionnaires. Post hoc analyses evaluated neurocognitive TEAE incidences during the first 11 and entire 55weeks of treatment and efficacy by patient age and drug-resistant status. Of the 217 patients who completed PREVAIL (USL255, n=103; placebo, n=114), 210 (97%) enrolled in PREVAIL OLE and were included in the ITT population. Across the entire 55-week treatment period, USL255 was generally safe and well tolerated, with low individual neurocognitive TEAE incidences. Seizure reduction was sustained across the year-long study and observed in patient subgroups, including those with highly drug-resistant seizures and those ≥50years of age. Improvements in CGI-C and QOLIE-31-P were also observed. The results of PREVAIL OLE are consistent with those from PREVAIL and demonstrate that adjunctive treatment with up to 400mg/day of USL255 may be a safe and effective treatment option for a variety of adult patients with refractory POS.

A long-term noninterventional safety study of adjunctive lacosamide therapy in patients with epilepsy and uncontrolled partial-onset seizures.

This noninterventional, observational, postauthorization safety study (SP0942, NCT00771927) evaluated the incidence of predefined cardiovascular- (CV) and psychiatric-related treatment-emergent adverse events (TEAEs), in patients with epilepsy and uncontrolled partial-onset seizures, when initiating adjunctive therapy with lacosamide or another approved antiepileptic drug (AED) according to standard medical practice. Active recording of predefined TEAEs of interest took place at three-monthly recommended visits for up to 12months. Of 1004 patients who received at least one dose of adjunctive AEDs, 511 initially added lacosamide therapy, 493 added another AED, 69 were ≥65years of age, and 72 took concomitant antiarrhythmic drugs. Patients in the lacosamide cohort had a higher median frequency of partial-onset seizures (6.0 versus 3.5 per 28days) despite taking more concomitant AEDs (84.9% versus 66.9% took ≥2) at baseline. Patients who added lacosamide took a modal dose of 200mg/day over the treatment period (n=501), and 50.1% (256/511) completed 12months of treatment. Fifty-one point nine percent (256/493) of patients who added another AED completed the study, with the most commonly added AED being levetiracetam (28.4%). Four patients (0.8%) in each cohort, all <65years of age, reported predefined CV-related TEAEs. None were considered serious or led to discontinuation. One event each of sinus bradycardia (lacosamide), atrioventricular block first degree (lacosamide), and syncope (other AED) were judged to be treatment-related. Another patient in the other AED cohort reported bradycardia while taking concomitant antiarrhythmic drugs. Predefined psychiatric-related TEAEs were reported by 21 patients (4.1%) in the lacosamide cohort and 27 patients (5.5%) in the other AED cohort. Depression was the most common to be treatment-related (7/11 and 12/18 of patients reporting treatment-related psychiatric TEAEs, respectively). Serious psychiatric-related TEAEs were reported by four patients who added lacosamide (two cases of depression, two of suicide attempt) and one who added another AED (depression). Seven deaths occurred, all of which were considered unrelated/unlikely related to study medication. This thorough evaluation revealed a low incidence of predefined CV- and psychiatric-related TEAEs in patients taking adjunctive AED therapy according to standard medical practice. No specific safety concerns related to adjunctive lacosamide therapy were noted.

Brivaracetam: First Global Approval.

Brivaracetam (Briviact(®)), a 4-n-propyl analogue of levetiracetam developed by UCB Pharma, has been approved in the EU as an adjunctive therapy for the treatment of partial-onset seizures. Brivaracetam binds to synaptic vesicle glycoprotein 2a (SV2A) in the brain with greater selectivity and 15- to 30-fold higher affinity than levetiracetam, as demonstrated in preclinical models, and has demonstrated efficacy in reducing the frequency of partial onset seizures in clinical trials. This article summarizes the milestones in the development of brivaracetam leading to this first approval for use as adjunctive therapy for uncontrolled partial-onset seizures in adults with epilepsy.

Levetiracetam extended release for the treatment of patients with partial-onset seizures: A long-term, open-label follow-up study

This was an open-label study (N01281 [NCT00419393]) assessing the long-term safety of extended-release levetiracetam (LEV XR) in patients with partial-onset seizures (POS); the study was a follow-up to a double-blind, randomized, historical controlled, multicenter, conversion to monotherapy study (N01280 [NCT00419094]). Eligible patients initially received LEV XR 2000 mg/day; dose adjustments and the addition of other antiepileptic drugs (AEDs) were permitted. Overall, 190 patients were enrolled, 189 (99.5%) received LEV XR (safety and efficacy populations) and 166 patients (87.4%) completed the study. The study duration in completed patients was 5.5-24.6 months. Mean daily dose of LEV XR was 2131 mg/day. Treatment-emergent adverse events (TEAEs) occurred in 126 patients (66.7%); most were of mild or moderate severity. Five patients (2.6%) had a TEAE that led to treatment discontinuation. Treatment-emergent serious adverse events occurred in 22 patients (11.6%). Twenty-six patients (13.8%) experienced a psychiatric TEAE. The median 7-day normalized POS frequency was: 1.38 at N01280 study baseline; 0.50 at the first visit of N01281 (last visit of N01280); and 0.00-0.36 between all subsequent visits. Overall, 171 patients (90.5%) entered the N01281 study on LEV XR monotherapy; 65.3% (32/49) of patients remained on monotherapy for 12 months and 47.1% (8/17) for 18 months. While remaining on LEV XR monotherapy, 27/139 patients (19.4%) were seizure-free at 6 months and 8/49 (16.3%) at 12 months. In conclusion, LEV XR was well tolerated when administered as long-term monotherapy or in combination with other AEDs in patients with inadequately controlled POS.

Efficacy of once-daily extended-release topiramate (USL255): A subgroup analysis based on the level of treatment resistance

Results from a previously conducted global phase III study (PREVAIL; NCT01142193) demonstrate the safety and efficacy of once-daily USL255, Qudexy™ XR (topiramate) extended-release capsules, as adjunctive treatment of drug-resistant partial-onset seizures (POSs). In this study, we report a post hoc analysis of PREVAIL data according to patient level of treatment resistance (based upon the number of concomitant antiepileptic drugs [AEDs] and lifetime AEDs) at baseline, with patients defined as either having “highly” drug-resistant seizures (≥2 concurrent AEDs and ≥4 lifetime AEDs) or having “less” drug-resistant seizures (1 concurrent AED or <4 lifetime AEDs) at baseline. For each subgroup, median percent reduction in POS frequency (primary endpoint), responder rate, Clinical Global Impression of Change (CGI-C), and Quality of Life in Epilepsy — Problems (QOLIE-31-P) survey were assessed. Of 249 PREVAIL patients, 115 were classified as having highly drug-resistant seizures (USL255: n=52, placebo: n=63), and 134 were classified as having less drug-resistant seizures (USL255: n=72, placebo: n=62) at baseline. For the primary endpoint, USL255 resulted in significantly better seizure outcomes compared with placebo regardless of drug-resistant status (P=.004 and P=.040 for “highly” and “less”, respectively). Responder rate was also significantly improved in patients with highly drug-resistant group (P=.023). The CGI-C scores indicated significant improvement in both subgroups (P=.003 and P=.013 for “highly” and “less”, respectively). On the QOLIE-31-P, a significant improvement on the seizure worry subscale for the group with less drug-resistant seizures was noted in USL255-treated patients compared with placebo-treated patients (P=.003); the overall score and all other subscales were not significantly different for both subgroups. We conclude that USL255 led to significant improvements across multiple outcomes compared with placebo, including in those classified as having highly drug-resistant seizures to prior treatment, making it a valuable treatment option for patients with epilepsy.

Two-year seizure reduction in adults with medically intractable partial onset epilepsy treated with responsive neurostimulation: final results of the RNS System Pivotal trial.

ObjectiveTo demonstrate the safety and effectiveness of responsive stimulation at the seizure focus as an adjunctive therapy to reduce the frequency of seizures in adults with medically intractable partial onset seizures arising from one or two seizure foci.MethodsRandomized multicenter double-blinded controlled trial of responsive focal cortical stimulation (RNS System). Subjects with medically intractable partial onset seizures from one or two foci were implanted, and 1 month postimplant were randomized 1:1 to active or sham stimulation. After the fifth postimplant month, all subjects received responsive stimulation in an open label period (OLP) to complete 2 years of postimplant follow-up.ResultsAll 191 subjects were randomized. The percent change in seizures at the end of the blinded period was −37.9% in the active and −17.3% in the sham stimulation group (p = 0.012, Generalized Estimating Equations). The median percent reduction in seizures in the OLP was 44% at 1 year and 53% at 2 years, which represents a progressive and significant improvement with time (p < 0.0001). The serious adverse event rate was not different between subjects receiving active and sham stimulation. Adverse events were consistent with the known risks of an implanted medical device, seizures, and of other epilepsy treatments. There were no adverse effects on neuropsychological function or mood.SignificanceResponsive stimulation to the seizure focus reduced the frequency of partial-onset seizures acutely, showed improving seizure reduction over time, was well tolerated, and was acceptably safe. The RNS System provides an additional treatment option for patients with medically intractable partial-onset seizures.

Efficacy of perampanel: a review of clinical trial data

The efficacy of adjunctive perampanel has been investigated in an extensive clinical development program across a broad, multinational population of patients with refractory partial-onset seizures. Further to the results of two Phase II dose-finding studies, perampanel was evaluated in three large Phase III registration studies at the predicted no-effect dose of 2 mg/day and the predicted effective doses of 4, 8, and 12 mg/day. In all three studies, perampanel 4, 8, and 12 mg/day consistently provided significant reductions in the frequency of partial-onset seizures compared with placebo. Improvements in responder rates and seizure freedom rates were also observed. In addition, data from recent interim analyses of extension studies have indicated that these efficacy outcomes may be maintained with long-term treatment. Overall, these studies form a solid evidence base to support the efficacy of adjunctive perampanel in the treatment of refractory partial-onset seizures.

A randomized, double‐blind, placebo‐controlled study of the efficacy, safety, and tolerability of adjunctive carisbamate treatment in patients with partial‐onset seizures

To assess the efficacy, safety, and tolerability of adjunctive carisbamate treatment at 800 mg/day and 1,200 mg/day in patients with partial-onset seizures (POS). Patients ≥ 16 years of age with an established diagnosis of POS for ≥ 1 year and uncontrolled on one to three antiepileptic drugs were enrolled. Eligible patients remained on stable doses of prescribed antiepileptic drugs for an 8-week pretreatment baseline phase and were then randomized (1:1:1) to receive carisbamate (800 mg/day or 1,200 mg/day), or placebo, for a 14-week double-blind phase. Primary efficacy endpoints were percentage reduction in POS frequency and responder rate (patients with ≥ 50% reduction in POS frequency) during the double-blind versus baseline phase. Five hundred forty-seven patients were randomized; 540 composed the intent-to-treat (ITT) analysis. Four hundred thirty-four patients (79%) completed the study. The median percent reduction from baseline to treatment phase in POS frequency was: 21% (placebo); 30% (carisbamate 800 mg); 36% (carisbamate 1,200 mg), and 32% (combined carisbamate doses). The combined carisbamate dose group was not significantly different from placebo for the median percent reduction of POS frequency (p = 0.20) or responder rate (p = 0.18). Therefore, the difference from placebo for the individual carisbamate dose groups was also considered nonsignificant, based on a prespecified step-down analysis. Dizziness was the most common treatment-emergent adverse event, with a higher incidence (≥ 5% difference) in the combined carisbamate group (31%) than placebo (9%); the incidence was higher with carisbamate 1,200 mg (32%, n = 58) than with carisbamate 800 mg (30%, n = 53). Adjunctive carisbamate therapy in patients with POS did not demonstrate efficacy across the dose range assessed versus placebo. No new safety findings were observed.

Antiepileptic and Antiepileptogenic Performance of Carisbamate after Head Injury in the Rat: Blind and Randomized Studies

Carisbamate (CRS) exhibits broad acute anticonvulsant activity in conventional anticonvulsant screens, genetic models of absence epilepsy and audiogenic seizures, and chronic spontaneous motor seizures arising after chemoconvulsant-induced status epilepticus. In add-on phase III trials with pharmacoresistant patients CRS induced < 30% average decreases in partial-onset seizure frequency. We assessed the antiepileptogenic and antiepileptic performance of subchronic CRS administration on posttraumatic epilepsy (PTE) induced by rostral parasaggital fluid percussion injury (rpFPI), which closely replicates human contusive closed head injury. Studies were blind and randomized, and treatment effects were assessed on the basis of sensitive electrocorticography (ECoG) recordings. Antiepileptogenic effects were assessed in independent groups of control and CRS-treated rats, at 1 and 3 months postinjury, after completion of a 2-week prophylactic treatment initiated 15 min after injury. The antiepileptic effects of 1-week CRS treatments were assessed in repeated measures experiments at 1 and 4 months postinjury. The studies were powered to detect ~50 and ~40% decreases in epilepsy incidence and frequency of seizures, respectively. Drug/vehicle treatment, ECoG analysis, and [CRS](plasma) determination all were performed blind. We detected no antiepileptogenic and an equivocal transient antiepileptic effects of CRS despite [CRS](plasma) comparable with or higher than levels attained in previous preclinical and clinical studies. These findings contrast with previous preclinical data demonstrating large efficacy of CRS, but agree with the average effect of CRS seen in clinical trials. The data support the use of rpFPI-induced PTE in the adolescent rat as a model of pharmacoresistant epilepsy for preclinical development.

Adjunctive levetiracetam in patients aged 1 month to

Background: In a recent double-blind, placebo-controlled study, adjunctive levetiracetam (LEV) was reported to be effective and well tolerated during 5-day treatment in patients aged 1 month to <4 years with partial-onset seizures. A study was planned to fulfill the regulatory requirement to evaluate the long-term safety of LEV as adjunctive therapy for partial-onset seizures in pediatric patients. Objective: This study evaluated the long-term effectiveness and tolerability of adjunctive LEV in infants and young children with partial-onset seizures. Methods: This was a prospective, open-label, outpatient, multicenter study (N01148; ClinicalTrials.gov identifier NCT00152516) conducted as an extension of a previously published study (N01009; NCT00175890). Patients were enrolled from 3 sources, as follows: (1) patients who had completed study N01009; (2) patients who had failed screening for entry into study N01009 but fulfilled the eligibility criteria for entry into this study; and (3) patients who were directly enrolled. The study consisted of a 2- to 4-week retrospective baseline period (and a 3- to 10-day prospective baseline period for directly enrolled patients), a 2- to 8-week uptitration/conversion period, and a maintenance period. Eligible patients were required to have epilepsy with partial-onset seizures, treated with a stable regimen of 1 or 2 antiepileptic drugs. Patients received adjunctive LEV, 20 to 80 mg/kg/d, for up to 48 weeks (total study duration). The primary variable for effectiveness was the percentage reduction from baseline in the weekly frequency of partial-onset seizures, as recorded in patients' diaries. Data for effectiveness were also analyzed by age strata (1 month to <1 year, 1 to <2 years, and 2 to <4 years). Neuropsychological assessment was conducted with the Bayley Scales of Infant Development, Second Edition (BSID-II). All analyses were performed on observed data, and the last-observation-carried-forward approach was not used. The intent-to-treat (ITT) population was defined as all patients who took at least one dose of LEV during the study. Treatment-emergent adverse events (TEAEs) were assessed by observation, spontaneous reporting, standard questions, review of diary cards, and neuropsychologists' clinical reports. Additional measures included physical and neurologic examinations, vital signs, ECGs, routine blood chemistry, and routine hematology assessments. Results: The study included 152 patients in the ITT population. In total, 51.3% (78/152) of the patients were male, and mean (SD) age was 23.5 (12.4) months. The mean LEV maintenance dose was 56.1 (16.2) mg/kg/d, and the median (Q1–Q3) treatment duration was 287.8 (209.0–295.5) days. Ninety-seven patients (63.8%) completed the study. The BSID-II subpopulation included 51 patients. During maintenance, the overall median (Q1–Q3) percentage reduction from baseline in the weekly frequency of partial-onset seizures was 56.0% (−10.9% to 92.8%), which was sustained over time and appeared comparable across the age strata (1 month to <1 year, n = 25, 50.9%; 1 to <2 years, n = 48, 58.0%; and 2 to <4 years, n = 59, 55.0%). The overall responder rate (ie, ≥50% reduction from baseline in weekly partial-onset seizures) was 53.8% (71/132), was maintained over time, and was consistent across the age strata (1 month to <1 year, 52.0%; 1 to <2 years, 56.3%; and 2 to <4 years, 52.5%). Mean BSID-II raw scores for psychomotor development and behavioral functioning remained static, whereas mental development appeared to improve over time, although this was not tested statistically. At least one TEAE was reported in 143 patients (94.1%). The most frequently reported TEAEs were pyrexia (60/152; 39.5%), upper respiratory tract infection (42/152; 27.6%), and vomiting (28/152; 18.4%). The most common TEAEs affecting the central nervous system were convulsion (25/152; 16.4%), irritability (19/152; 12.5%), and somnolence (16/152; 10.5%). Most TEAEs (77.0%) were mild or moderate in intensity. Conclusion: Adjunctive LEV treatment for up to 48 weeks was associated with effective and sustained seizure control and had an acceptable tolerability profile in this small, selected population of infants and young children aged 1 month to <4 years with partial-onset seizures.

Lacosamide for the treatment of partial-onset seizures

Lacosamide is a recently approved antiepileptic drug for the adjunctive treatment of partial-onset seizures in adults. It is a functionalized amino acid with a novel mechanism of action, possesses excellent oral absorption, has negligible protein binding, interacts minimally with other antiepileptic drugs and is excreted mainly in the urine. It is efficacious at significantly reducing the frequency of partial-onset seizures by approximately 36–39% at doses of 400 mg/day, compared with just 10–20% reduction for placebo. It is generally well tolerated, with its main dose-related side effect being dizziness. It has no known endorgan toxicities, although it can increase the PR interval. It is likely to be an important contribution to the treatment of individuals with refractory partial-onset seizures.

Carisbamate as adjunctive treatment of partial onset seizures in adults in two randomized, placebo‐controlled trials

To assess the efficacy, safety, and tolerability of the investigational drug carisbamate as adjunctive treatment for partial-onset seizures (POS). Two identical, randomized, placebo-controlled, double-blind studies were conducted in adults with POS uncontrolled for >or=1 year. Therapy-refractory epilepsy patients (>or=16 years) remained on stable doses of prescribed antiepileptic drugs (<or=2) for an 8-week prospective baseline phase and were then randomized (1:1:1) to carisbamate 200 mg/day, carisbamate 400 mg/day, or placebo, for a 12-week double-blind phase. Primary efficacy end points were percent reduction in seizure frequency and responder rate (patients with >or=50% reduction in POS frequency) during the double-blind phase compared with the prospective baseline phase. Of the 565 patients randomized in study 1, 93% completed the study; of the 562 randomized in study 2, 94% completed the study. Patient characteristics were similar across both studies and treatment arms: mean age, 35 years (study 1, range 16-75 years) and 36 years (study 2, range 16-74 years); approximately 50% were men. Treatment with carisbamate 400 mg/day resulted in significant improvement (p < 0.01) in both efficacy measures compared with placebo in study 1 but not in study 2. Carisbamate 200 mg/day did not differ statistically from placebo in either study. Among the most common treatment-emergent adverse events (>or=5% in any group), those with an incidence exceeding placebo (>or=3%) were dizziness (400 mg/day group) and somnolence. Carisbamate 400 mg/day was effective in patients with refractory partial-onset seizures in one of these global studies. More than 200 mg/day of carisbamate is required for efficacy. Carisbamate was well-tolerated in both studies.

Neurocognitive effects of adjunctive levetiracetam in children with partial‐onset seizures: A randomized, double‐blind, placebo‐controlled, noninferiority trial

Evaluate potential neurocognitive effects of adjunctive levetiracetam in children with inadequately controlled partial-onset seizures (POS). Randomized, double-blind, placebo-controlled, noninferiority safety study. Children (4-16 years; IQ > or =65) with > or =1 POS during 4 weeks before screening despite taking 1-2 antiepileptic drugs (AEDs) were randomized (2:1) to levetiracetam (20-60 mg/kg/day) or placebo for 12 weeks. Ninety-nine patients were randomized with 98 (levetiracetam 64, placebo 34) in intent-to-treat (ITT) and 73 (levetiracetam 46, placebo 27) in per protocol (PP) populations. Primary cognitive assessment was the Leiter International Performance Scale-Revised Attention and Memory Battery with the memory screen composite score change from baseline as the primary endpoint. PP Least Square Mean [LSM (standard error)] were 5.36 (1.78) for levetiracetam; 5.17 (2.33) for placebo; difference [two-sided 90% confidence interval (CI)] 0.19 (-4.69, 5.08). Levetiracetam was noninferior to placebo because the 90% CI lower bound was greater than the defined noninferiority margin (-9.0). There were no statistically significant differences between groups in Wide Range Assessment of Memory and Learning-2 indexes and Leiter-R Examiner's Rating Scale scores. Median reductions from baseline in weekly POS frequency were 91.5% versus 26.5% for levetiracetam versus placebo; > or =50% responder rates: 62.5% versus 41.2%; seizure freedom rates: 46.9% versus 8.8% (ITT). Adverse events were reported by 89.1% levetiracetam-treated and 85.3% placebo-treated patients; those reported by > or =10% levetiracetam patients and more often with levetiracetam were headache, nasopharyngitis, fatigue, vomiting, somnolence, and aggression. Neurocognitive effects were no different in pediatric patients with POS treated with adjunctive levetiracetam or placebo. Levetiracetam was effective and well tolerated.

Adjunctive levetiracetam in infants and young children with refractory partial‐onset seizures

To evaluate the efficacy and tolerability of adjunctive levetiracetam in very young children (aged 1 month to <4 years) with partial-onset seizures inadequately controlled with one or two antiepileptic drugs. This multicenter, double-blind, randomized, placebo-controlled study consisted of a 48-h inpatient baseline video-EEG (electroencephalography) and a 5-day inpatient treatment period (1-day up-titration; 48-h evaluation video-EEG in the last 2 days). Children who experienced at least two partial-onset seizures during the 48-h baseline video-EEG were randomized to either levetiracetam [40 mg/kg/day (age 1 to <6 months); 50 mg/kg/day (age >or=6 months to <4 years] or placebo. Of 175 patients screened, 116 patients were randomized [60 levetiracetam; 56 placebo; intent-to-treat (ITT) population], and 111 completed the study. The responder rate in average daily partial-onset seizures frequency (48-h video-EEG monitoring; primary efficacy variable) was 43.1% for levetiracetam [modified ITT (mITT) = 58] versus 19.6% for placebo (mITT = 51; p=0.013), with odds ratio for response 3.11 [95% confidence interval (CI), 1.22-8.26]. The median percent reduction from baseline in average daily partial-onset seizure frequency was 43.6% for levetiracetam and 7.1% for placebo with a median difference between treatment groups of 39.2% (95% CI, 17.5-62.2; p < 0.001). In general, levetiracetam was well tolerated. Treatment-emergent adverse events were reported by 55.0% levetiracetam- and 44.6% placebo-treated patients (ITT population). The most frequently reported adverse events were somnolence (13.3% levetiracetam, 1.8% placebo) and irritability (11.7% levetiracetam, 0% placebo). Adjunctive levetiracetam is an efficacious and well-tolerated treatment for partial-onset seizures in infants and young children.

Multicenter double‐blind, randomized, placebo‐controlled trial of levetiracetam as add‐on therapy in Chinese patients with refractory partial‐onset seizures

To evaluate efficacy and tolerability of levetiracetam (LEV; Keppra) as add-on therapy in Chinese patients with refractory partial-onset seizures. In this multicenter, double-blind, randomized, placebo-controlled trial, 206 patients aged 16-70 years with uncontrolled partial-onset seizures were randomized to receive LEV (n =103) or placebo (n =103); 202 patients (LEV, n =102; placebo, n = 100) comprised the intent-to-treat population. An 8-week historical baseline period confirmed eligibility according to seizure count. The 16-week treatment period consisted of a 4-week up-titration period (LEV, 1,000-3,000 mg/day in two equal divided doses) followed by a 12-week maintenance period. Efficacy assessments were based on weekly frequency of partial-onset seizures during the 16-week treatment period. LEV significantly decreased weekly partial-onset seizure frequency over placebo by 26.8% (p < 0.001). Median percentage reductions in weekly partial-onset seizure frequency from historical baseline were 55.9% for LEV and 13.7% for placebo (p < 0.001). The >or=50% responder rates were 55.9% for LEV, compared with 26.0% for placebo (p < 0.001). Freedom from partial-onset seizures during treatment period was achieved by 11 LEV patients (10.8%) and 2 placebo patients (2.0%) (p = 0.012). Adverse events were reported by 65 LEV-treated patients (63.1%) and 62 placebo-treated patients (60.2%); most were of mild-to-moderate intensity. The most common adverse events were somnolence (LEV, 17.5%; placebo, 17.5%), decreased platelet count (LEV, 9.7%; placebo, 9.7%), and dizziness (LEV, 7.8%; placebo, 13.6%). Add-on LEV was effective and well-tolerated in Chinese patients with refractory partial-onset seizures.

Lacosamide: pharmacology, mechanisms of action and pooled efficacy and safety data in partial-onset seizures

Lacosamide is an antiepileptic drug approved in the USA and Europe as adjunctive therapy for partial-onset seizures. Studies suggest that lacosamide selectively enhances slow inactivation of voltage-gated sodium channels and possibly interacts with collapsin response mediator protein-2. The efficacy of lacosamide has been shown in animal models of epilepsy and Phase II/III clinical trials. Pharmacokinetic studies show that it is renally excreted, minimally bound to plasma proteins and has no known clinically relevant drug–drug interactions. Clinical trials show that lacosamide is well tolerated; the most common adverse events were dizziness, nausea and vomiting. In a Phase II/III pooled analysis, lacosamide 200 and 400 mg/day significantly reduced partial-onset seizure frequency and improved the 50% responder rate compared with placebo.

Randomized, controlled, dose-ranging trial of carisbamate for partial-onset seizures

To evaluate the efficacy, safety, and tolerability of carisbamate (CRS), an investigational drug, as adjunctive treatment for partial-onset seizures in adults. A randomized, double-blind, placebo-controlled, multicenter, dose-ranging study was conducted in 12 countries. Patients counted seizures during an 8-week baseline period, and then, if eligible, entered a double-blind phase consisting of a 4-week dose-titration period (target CRS doses: 100, 300, 800, or 1,600 mg/d or placebo in two divided doses) and a 12-week maintenance period. The primary efficacy variable was percent reduction in partial-onset seizure frequency during the double-blind phase compared with pretreatment baseline. Safety data and responder rates were also assessed. Five hundred thirty-seven patients were randomized, and 82% completed the study. In the intent-to-treat population (n = 533), CRS at doses of > or =300 mg/d (p < or = 0.006) reduced the frequency of partial-onset seizures vs placebo: 6% (placebo) vs 24% (300 mg/d), 21% (800 mg/d), and 29% (1,600 mg/d) for CRS. Adverse events consisted primarily of CNS effects, and led to discontinuation of drug in 8% of the placebo group vs 5% (100 mg/d), 6% (300 mg/d), 12% (800 mg/d), and 19% (1,600 mg/d) of the CRS groups. Carisbamate at doses of 300, 800, and 1,600 mg/d was effective as adjunctive therapy for reducing the frequency of partial-onset seizures.

Retigabine: Has the Orphan Found a Home?

Randomized, Multicenter, Dose-Ranging Trial of Retigabine for Partial-Onset Seizures. Porter RJ, Partiot A, Sachdeo R, Nohria V, Alves WM; 205 Study Group. Neurology 2007;68(15):1197–1204. OBJECTIVE: To evaluate the efficacy and safety of retigabine 600, 900, and 1,200 mg/day administered three times daily as adjunctive therapy in patients with partial-onset seizures. METHODS: A multicenter, randomized, double-blind, placebo-controlled trial was performed. After an 8-week baseline phase, patients were randomized to a 16-week double-blind treatment period (8-week forced titration and 8-week maintenance) followed by either tapering or entry into an open-label extension study. Primary efficacy was the percentage change from baseline in monthly seizure frequency and compared across treatment arms. Secondary efficacy comparisons included the proportion of patients experiencing 50% reduction in seizure frequency (responder rate), emergence of new seizure types, and physician assessment of global clinical improvement. Safety/tolerability assessments included adverse events (AEs), physical and neurologic examinations, and clinical laboratory evaluations. Efficacy analyses were performed on the intent-to-treat population. RESULTS: Of the 399 randomized patients, 279 (69.9%) completed the double-blind treatment period. The median percent change in monthly total partial seizure frequency from baseline was −23% for 600 mg/day, −29% for 900 mg/day, and −35% for 1,200 mg/day vs −13% for placebo ( p &lt; 0.001 for overall difference across all treatment arms). Responder rates for retigabine were 23% for 600 mg/day, 32% for 900 mg/day ( p = 0.021), and 33% for 1,200 mg/day ( p = 0.016), vs 16% for placebo. The most common treatment-emergent AEs were somnolence, dizziness, confusion, speech disorder, vertigo, tremor, amnesia, abnormal thinking, abnormal gait, paresthesia, and diplopia. CONCLUSION: Adjunctive therapy with retigabine is well tolerated and reduces the frequency of partial-onset seizures in a dose-dependent manner.