Challenges in identifying Lennox-Gastaut syndrome in adults: A case series illustrating its changing nature

Real-world use of the updated refractory epilepsy screening tool for Lennox-Gastaut syndrome

OBJECTIVE

To evaluate the Refractory Epilepsy Screening Tool for Lennox-Gastaut Syndrome (REST-LGS) for real-world identification of LGS in adults and to develop a scoring system for the tool.

METHODS

A retrospective chart review of adults with drug resistant epilepsy (DRE) and intellectual development disorder (IDD) was conducted by 2 primary care providers blinded to diagnosis. The REST-LGS was designed via the Modified Delphi Consensus and was previously validated. This tool consists of 8 criteria (4 major, 4 minor) considered indicative of LGS. To account for missing data in the earlier validation study and to evaluate applicability in a real-world setting, the REST-LGS was refined to include a scoring system in which major criteria were more heavily weighted than minor criteria, producing categories of "likely" (>11 points), "possible" (8-11 points), and "unlikely" (<8 points) LGS. Statistical analyses were descriptive.

RESULTS

Of the 100 patients included in the analysis, data for slow spike-waves in electroencephalography and seizure onset age - both major REST-LGS criteria - were missing for 46% and 42% of patients, respectively. The majority of patients met 4 of the 8 REST-LGS criteria (cognitive impairment since childhood, 71%; persistent seizures despite a trial of ≥2 antiseizure medications, 65%; seizure onset before the age of 12 years, 57%; ≥2 seizure types, 56%). All 4 major criteria were met in 22 patients (22%). The percentages of patients considered "likely," "possible," or "unlikely" to have LGS were 26%, 30%, and 44%, respectively. Of the 74 patients without a previous LGS diagnosis, 42 (57%) were identified as "possible" or "likely" to have LGS using REST-LGS.

SIGNIFICANCE

In this analysis, the validated REST-LGS was evaluated in a real-world setting. The majority of previously undiagnosed patients were identified via REST-LGS as "possible" or "likely" to have LGS. Extensive missing data highlights challenges of LGS diagnosis in adults.

PLAIN LANGUAGE SUMMARY

There is a need to identify adult patients with Lennox-Gastaut syndrome (LGS) so they can receive appropriate treatment. The Refractory Epilepsy Screening Tool for LGS (REST-LGS) questionnaire was designed by experts to identify whether patients with seizures that are not controlled by medications may have LGS. In this study, 2 physicians completed the REST-LGS using charts for 100 patients who experience seizures not controlled by medications. Of the patients who were previously diagnosed as not having LGS, the majority were "likely" or "possible" to have LGS based on the REST-LGS; therefore, the REST-LGS can identify patients for further evaluation.

Consensus panel recommendations for the optimization of EPIDIOLEX® treatment for seizures associated with Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex

Following the approval of Epidiolex® (cannabidiol; CBD) for the treatment of seizures associated with Lennox-Gastaut syndrome (LGS), Dravet syndrome (DS), and tuberous sclerosis complex (TSC), healthcare professionals (HCPs) have had substantial experience in treating patients with Epidiolex. However, confusion still remains among HCPs, caregivers, and patients regarding dosing, drug interactions, safety monitoring, and differentiation between Epidiolex and nonapproved CBD products. To establish consensus recommendations for Epidiolex treatment optimization in LGS, DS, and TSC, a panel of seven HCPs with expertise in epilepsy was convened. Panelists participated in a premeeting survey based on a literature review of Epidiolex for the treatment of LGS, DS, and TSC, and survey responses were compiled for discussion. A modified Delphi method was used to assess agreement among panelists regarding recommendation statements following two rounds of discussion. Panelists identified two broad themes - overcoming barriers to initiation and optimization of treatment for seizures associated with LGS, DS, and TSC - for consensus guidelines. Accurate identification of patients with these rare epilepsies is critical for optimization of Epidiolex treatment. Providers should differentiate Epidiolex from nonapproved CBD products and set expectations for the therapeutic effect and safety/tolerability of Epidiolex. Initial target dose and titration rate should be individualized by baseline variables, prior response to antiseizure medications, and therapeutic goals. Awareness of strategies to manage adverse events and concomitant medications, including drug-drug interactions, is critical. Tracking response to the maximum tolerated dose is an important measure of effectiveness. These consensus recommendations provide real-world experience from neurology HCPs with experience in prescribing Epidiolex and can inform optimal use of Epidiolex for the treatment of seizures associated with LGS, DS, and TSC. PLAIN LANGUAGE SUMMARY: Epidiolex® (cannabidiol) is approved for treating seizures in Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex. Although healthcare professionals have experience in treating patients with Epidiolex, there is a need for better understanding of dosing, drug interactions, and safety of this drug. Therefore, a group of epilepsy experts developed guidelines for best practices in Epidiolex treatment. Two main areas were identified: overcoming barriers to starting Epidiolex and considerations related to Epidiolex dosing. Within these areas, topics, including correct disease identification, managing adverse events, and determining individualized dose, were discussed. These guidelines provide real-world experience to inform optimal Epidiolex use.

Proposed anti-seizure medication combinations with rufinamide in the treatment of Lennox-Gastaut syndrome: Narrative review and expert opinion

Lennox-Gastaut syndrome (LGS) is a severe, chronic, complex form of early childhood-onset epilepsy characterized by multiple seizure types, generalized slow (≤2.5 Hz) spike-and-wave activity and other electroencephalography abnormalities, and cognitive impairment. A key treatment goal is early seizure control, and several anti-seizure medications (ASMs) are available. Due to the low success rate in achieving seizure control with monotherapy and an absence of efficacy data supporting any particular combination of ASMs for treating LGS, a rational approach to selection of appropriate polytherapy should be applied to maximize benefit to patients. Such "rational polytherapy" involves consideration of factors including safety (including boxed warnings), potential drug-drug interactions, and complementary mechanisms of action. Based on the authors' clinical experience, rufinamide offers a well-considered first adjunctive therapy for LGS, particularly in combination with clobazam and other newer agents for LGS, and may be particularly useful for reducing the frequency of tonic-atonic seizures associated with LGS.

The burden of illness in Lennox-Gastaut syndrome: a systematic literature review

BACKGROUND

Lennox-Gastaut syndrome (LGS) is a severe developmental and epileptic encephalopathy characterized by drug-resistant epilepsy with multiple seizure types starting in childhood, a typical slow spike-wave pattern on electroencephalogram, and cognitive dysfunction.

METHODS

We performed a systematic literature review according to the PRISMA guidelines to identify, synthesize and appraise the burden of illness in LGS (including "probable" LGS). Studies were identified by searching MEDLINE, Embase and APA PsychInfo, Cochrane's database of systematic reviews, and Epistemonikos. The outcomes were epidemiology (incidence, prevalence or mortality), direct and indirect costs, healthcare resource utilization, and patient and caregiver health-related quality of life (HRQoL).

RESULTS

The search identified 22 publications evaluating the epidemiology (n = 10), direct costs and resource (n = 10) and/or HRQoL (n = 5). No studies reporting on indirect costs were identified. With no specific ICD code for LGS in many regions, several studies had to rely upon indirect methods to identify their patient populations (e.g., algorithms to search insurance claims databases to identify "probable" LGS). There was heterogeneity between studies in how LGS was defined, the size of the populations, ages of the patients and length of the follow-up period. The prevalence varied from 4.2 to 60.8 per 100,000 people across studies for probable LGS and 2.9-28 per 100,000 for a confirmed/narrow definition of LGS. LGS was associated with high mortality rates compared to the general population and epilepsy population. Healthcare resource utilization and direct costs were substantial across all studies. Mean annual direct costs per person varied from $24,048 to $80,545 across studies, and home-based care and inpatient care were significant cost drivers. Studies showed that the HRQoL of patients and caregivers was adversely affected, although only a few studies were identified. In addition, studies suggested that seizure events were associated with higher costs and worse HRQoL. The risk of bias was low or moderate in most studies.

CONCLUSIONS

LGS is associated with a significant burden of illness featuring resistant seizures associated with higher costs and worse HRQoL. More research is needed, especially in evaluating indirect costs and caregiver burden, where there is a notable lack of studies.

Case Report: Late-Onset Lennox-Gastaut Syndrome Treated With Stereotactic Electroencephalography-Guided Radiofrequency Thermocoagulation Before Craniotomy

The onset of Lennox-Gastaut syndrome (LGS), a severe epilepsy syndrome, is typically before 8 years of age. Late-onset LGS (with onset in adolescence and adulthood) is relatively rare clinically and has some differences from classical LGS. Herein, we describe the case of a patient with late-onset LGS and provide a literature review of such cases. The patient had focal epilepsy onset at 8 years of age. After a 9-year evolution, he suffered seizures of different types and had a diagnosis of late-onset LGS. Drug treatment was ineffective. Nothing was found on stereotactic electroencephalography (SEEG) and magnetic resonance imaging (MRI) during the course of the disease. After the second presurgical evaluation, we found a suspicious focus on high-resolution structural MRI which was verified by SEEG at last. After SEEG-guided radiofrequency thermocoagulation (RFTC), his seizures were controlled, and his cognitive function and quality of living clearly improved. However, his seizures recurred 2 years later, and he underwent left occipital resection. Thereafter, his seizures have been controlled until now. This case emphasizes the importance of high-resolution structural MRI in the treatment of LGS. Furthermore, it suggests that late-onset LGS may be caused by focal lesions and evolve from focal epilepsy. Thus, characterizing the clinical symptoms and performing individualized electroencephalographic follow-up are both very important. Additionally, the clinical outcome in this case implies the value and limitations of RFTC in patients with epilepsy and a clear focal lesion. Moreover, this case further supports differences between late-onset and classical LGS in terms of clinical manifestation, cognitive changes, prognosis, and treatment.

Efficacy and Safety of Fenfluramine for the Treatment of Seizures Associated With Lennox-Gastaut Syndrome: A Randomized Clinical Trial

Question

Is adjunctive fenfluramine effective in patients with Lennox-Gastaut syndrome (LGS)?

Findings

In this randomized clinical trial of 263 patients with LGS, use of 0.7-mg/kg/d fenfluramine resulted in a greater reduction in drop seizures than with placebo, more patients achieving a 50% or greater reduction in drop seizure frequency, and greater reduction in generalized tonic-clonic seizure frequency. Treatment-emergent adverse events included decreased appetite, but no patient developed valvular heart disease or pulmonary hypertension.

Meaning

Findings from this trial suggest that fenfluramine may be a safe and effective treatment option for patients with LGS.

Importance

New treatment options are needed for patients with Lennox-Gastaut syndrome (LGS), a profoundly impairing, treatment-resistant, developmental and epileptic encephalopathy.

Objective

To evaluate the efficacy and safety of fenfluramine in patients with LGS.

Design, Setting, and Participants

This multicenter, double-blind, placebo-controlled, parallel-group randomized clinical trial was conducted from November 27, 2017, to October 25, 2019, and had a 20-week trial duration. Patients were enrolled at 65 study sites in North America, Europe, and Australia. Included patients were aged 2 to 35 years with confirmed diagnosis of LGS and experienced 2 or more drop seizures per week during the 4-week baseline. Using a modified intent-to-treat method, data analysis was performed from November 27, 2017, to October 25, 2019. The database lock date was January 30, 2020, and the date of final report was September 11, 2021.

Interventions

Patients were randomized to receive either a 0.7-mg/kg/d or 0.2-mg/kg/d (maximum 26 mg/d) dose of fenfluramine or placebo. After titration (2-week period), patients were taking their randomized dose for 12 additional weeks.

Main Outcomes and Measures

Primary efficacy end point was percentage change from baseline in drop seizure frequency in patients who received 0.7 mg/kg/d of fenfluramine vs placebo.

Results

A total of 263 patients (median [range] age, 13 [2-35] years; 146 male patients [56%]) were randomized to the 0.7-mg/kg/d fenfluramine group (n = 87), 0.2-mg/kg/d fenfluramine group (n = 89), or placebo group (n = 87). The median percentage reduction in frequency of drop seizures was 26.5 percentage points in the 0.7-mg/kg/d fenfluramine group, 14.2 percentage points in the 0.2-mg/kg/d fenfluramine group, and 7.6 percentage points in the placebo group. The trial met its primary efficacy end point: patients in the 0.7-mg/kg/d fenfluramine group achieved a −19.9 percentage points (95% CI, −31.0 to −8.7 percentage points; P = .001) estimated median difference in drop seizures from baseline vs placebo. More patients in the 0.7-mg/kg/d fenfluramine group achieved a 50% or greater response (22 of 87 [25%]; P = .02) vs placebo (9 of 87 [10%]). Site investigators and caregivers gave a much improved or very much improved rating on the Clinical Global Impression of Improvement scale to more patients in the 0.7-mg/kg/d fenfluramine group than patients in the placebo group (21 [26%] vs 5 [6%]; P = .001). The seizure subtype that appeared most responsive to fenfluramine was generalized tonic-clonic seizure (120 of 263 [46%]), with a decrease in frequency of 45.7% in the 0.7-mg/kg/d fenfluramine group and 58.2% in the 0.2-mg/kg/d fenfluramine group compared with an increase of 3.7% in the placebo group. Most common treatment-emergent adverse events included decreased appetite (59 [22%]), somnolence (33 [13%]), and fatigue (33 [13%]). No cases of valvular heart disease or pulmonary arterial hypertension were observed.

Conclusions and Relevance

Results of this trial showed that, in patients with LGS, fenfluramine compared with placebo provided a significantly greater reduction in drop seizures and may be a particularly advantageous choice in patients who experience generalized tonic-clonic seizures.

Trial Registration

ClinicalTrials.gov Identifier: NCT03355209

Rare and Complex Epilepsies from Childhood to Adulthood: Requirements for Separate Management or Scope for a Lifespan Holistic Approach?

PURPOSE

In this descriptive review, we describe current models of transition in rare and complex epilepsy syndromes and propose alternative approaches for more holistic management based on disease biology.

RECENT FINDINGS

Previously published guidance and recommendations on transition strategies in individuals with epilepsy have not been systematically and uniformly applied. There is significant heterogeneity in models of transition/transfer of care across countries and even within the same country. We provide examples of the most severe epilepsy and related syndromes and emphasise the limited data on their outcome in adulthood. Rare and complex epilepsy syndromes have unique presentations and require high levels of expertise and multidisciplinary approach. Lifespan clinics, with no transition, but instead continuity of care from childhood to adulthood with highly specialised input from healthcare providers, may represent an alternative effective approach. Effectiveness should be measured by evaluation of quality of life for both patients and their families/caregivers.

Prevalence, healthcare resource utilization and mortality of Lennox-Gastaut syndrome: retrospective linkage cohort study

PURPOSE

To retrospectively investigate the prevalence, demography, antiseizure medication (ASM) usage, healthcare resource utilization (HCRU), and mortality of patients with Lennox-Gastaut syndrome (LGS) in primary and secondary care in the UK.

METHODS

Patients with confirmed LGS were anonymously identified from the UK Clinical Practice Research Datalink (CPRD) GOLD database (01/01/1987-31/1b0/2018) using the LGS Read Code (F250500). Probable LGS was identified using the International Classification of Diseases-10/Read Code for epilepsy (Hospital Episode Statistics [HES]/CPRD) plus rufinamide prescription. Period prevalence was calculated based on patients enrolled in CPRD GOLD and alive in 2017. CPRD data were linked to HES to calculate HCRU, and to the Office for National Statistics mortality registry.

RESULTS

Period prevalence of LGS was 0.578/10,000 (n = 180), with 74 and 106 patients identified with confirmed (0.289/10,000) and probable LGS (0.420/10,000). Mean (max) ASM usage was ~1 (3) per year. In confirmed LGS, valproate (72%), lamotrigine (69%), and clobazam (66%) were the most commonly prescribed ASMs. HCRU (per patient-year) was similar in confirmed and probable LGS and mostly consisted of primary care general practitioner consultations (4-6), outpatient visits (5-10), inpatient admissions (1-4), and A&E visits (1). During the follow-up period, 18 patients died with crude mortality rates of 6.12 (confirmed LGS) and 4.17 (probable LGS) deaths per 1000 person-years.

CONCLUSION

Prevalence of LGS appears low in the UK. The similarly high HCRU and mortality rates in confirmed and probable LGS support the validity and specificity of the probable LGS algorithm and high burden of LGS.

The unchanging face of Lennox-Gastaut syndrome in adulthood

PURPOSE

Lennox-Gastaut syndrome (LGS) is a severe childhood-onset epileptic encephalopathy characterized by the presence of multiple types of intractable seizures, cognitive impairment, and specific electroencephalogram (EEG) patterns. The aim of this study was to investigate the electroclinical features of patients with LGS during adulthood.

METHODS

We retrospectively identified the medical records of 20 patients aged over 18 years with a diagnosis of LGS from 3896 patients with epilepsy.

RESULTS

Thirteen (65 %) patients were male. The mean age of the patients was 23.4 ± 7.1 (min-max; 18-43) years, and the mean follow-up period was 5.6 ± 4.5 (min-max; 1-14) years. The etiology was identified in 11 (55 %) patients. None of the patients achieved seizure freedom. The most prevalent seizure types were atypical absences in 14 (70 %) patients, tonic seizures in 13 (65 %) patients, and atonic seizures in 11 (55 %) patients. One (5 %) patient was diagnosed as having psychogenic non-epileptic seizures. Mental retardation was reported in all patients and only half of them could walk independently. All patients had drug-resistant seizures and 16 (80 %) patients were on polytherapy. A vagus nerve stimulator was implanted into ten (50 %) patients and five reported 50-80 % seizure reduction. Ketogenic diet was administered to two (10 %) patients and epilepsy surgery was performed in two (10 %) patients with no significant benefit.

CONCLUSIONS

Paying attention to all factors of seizure outcomes, cognitive impairment, and ambulatory status, all patients were dependent on caregivers for daily living abilities. LGS has life-long persistence with poor outcomes, even during adulthood.

Validating Coding for the Identification of Pediatric Treatment Resistant Epilepsy Patients

The International Classification of Diseases (ICD) system includes sub codes to indicate that an individual with epilepsy is treatment resistant. These codes would be a valuable tool to identify individuals for quality improvement and population health, as well as for recruitment into clinical trials. However, the accuracy of these codes is unclear. We performed a single center cross sectional study to understand the accuracy of ICD codes for treatment resistant epilepsy. We identified 344 individuals, roughly half with treatment resistant epilepsy The ICD code had a sensitivity of 90% (147 of 164) and specificity of 86% (155 of 180). The miscoding of children with refractory epilepsy was attributed to the following reasons: 5 patients had epilepsy surgery, 4 had absence epilepsy, 4 patients were seen by different providers, and 1 patient was most recently seen in movement disorders clinic. ICD codes accurately identify children with treatment resistant epilepsy.

Expert opinion: Proposed diagnostic and treatment algorithms for Lennox-Gastaut syndrome in adult patients

Lennox-Gastaut syndrome (LGS) is a severe developmental epileptic encephalopathy diagnosed in childhood that persists through adolescence and into adulthood. While the characteristics of LGS in pediatric patients are well defined, including "drop attacks", interictal slow spike and wave electroencephalogram (EEG) activity, and intellectual disability, these features can evolve over time, and different EEG activities may be present in adult patients with LGS. This may result in missed diagnoses in these patients and subsequent challenges for the adequate treatment of their seizures. Based on discussions held during the LGS Transition of Care advisory board meeting and thereafter, we developed proposed diagnostic and treatment algorithms for LGS in adult patients. We highlight readily available assessments to facilitate diagnosis of LGS, based on past medical history and physical examination. The LGS diagnostic algorithm recommends that clinicians consider the occurrence of wider seizure types and abnormal EEG activities to be potentially indicative of LGS. Seizure types may include atypical absence seizures, myoclonic seizures, focal seizures, and tonic-clonic seizures, and EEG may demonstrate background slowing, focal or multifocal epileptiform discharges, and diffuse fast rhythms during sleep, among other activities. Extended EEG during sleep and video-EEG should be used in equivocal cases. Treatment of LGS in adult patients should incorporate both antiseizure drug (ASD) therapy and nonpharmacologic approaches. Frequent reassessment of patients is considered a central aspect. ASDs were categorized based on order of preference for use in the treatment of LGS; Tier 1 comprises recommended first-line ASDs, and includes valproate, clobazam, lamotrigine, rufinamide, topiramate, and cannabidiol. Other treatment options include diet, neurostimulation, and surgical approaches. Developments with the potential to improve diagnosis in the future include genetic screening, while novel ASDs and advances in neurostimulation techniques may provide valuable treatment options. These algorithms should be frequently revisited to incorporate improved techniques and therapies.

Development of a classifier to identify patients with probable Lennox-Gastaut syndrome in health insurance claims databases via random forest methodology

Objective: Describe the development of a claims-based classifier utilizing machine learning to identify patients with probable Lennox-Gastaut syndrome (LGS) from six state Medicaid programs. Methods: Patients were included if they had ≥2 medical claims ≥30 days apart for specified or unspecified epilepsy, excluding those with ≥1 claim for petit mal status. The LGS classifier utilized a random forest algorithm, a compilation of thousands of binary decision trees in which machine-generated predictor variables split the data set into branches that predict the presence or absence of LGS. To construct the splitting rules, the importance of each candidate variable was determined by calculating the mean decrease in Gini impurity. Training and testing were performed on two data sets (30% and 70%) using a "true" LGS and non-LGS patient population. Performance was compared with logistic regression and single tree methodology. Results: Using a 60% probability threshold, which yielded the highest sensitivity (97.3%) and specificity (95.6%), the classifier identified approximately 4% of patients with epilepsy as probable LGS. The most important input variables included number of distinct antiepileptic drugs received, epilepsy-related outpatient/inpatient visits, electroencephalogram procedures and claims for delayed development. The random forest methodology outperformed logistic regression and single tree methodology. Most of the important LGS predictor characteristics identified by the classifier were statistically significantly associated with LGS status (p < .05). Conclusions: The claims-based LGS classifier showed high sensitivity and specificity, outperformed single tree and logistic regression methodologies and identified a prevalence of probable LGS that was similar to previously published estimates.

Late-onset Lennox-Gastaut syndrome: Diagnostic evaluation and outcome

Background

We describe the clinical features and outcome in patients with late-onset Lennox-Gastaut syndrome (LGS).

Methods

Adult patients evaluated between January 1, 2000, and March 1, 2017, who presented with onset of LGS ≥10 years were identified. Data abstracted included age at seizure onset, seizure types, etiology, treatments, EEG and neuroimaging results, cerebrospinal fluid (CSF) findings, and autoimmune evaluation.

Results

Ten patients (8 females) were identified. The mean age at onset of seizures consistent with LGS was 16.5 years (range, 10-32 years). Seizure types included tonic, atonic, and tonic-clonic seizures (all), myoclonic seizures (n = 3), and atypical absence seizures (n = 7). Five patients had normal intellectual function at onset. Prolonged video-EEG monitoring recorded seizures and generalized interictal epileptiform discharges in all. All patients had drug-resistant epilepsy (range of antiseizure drugs tried, 7-16). Two patients had a history of intrathecal methotrexate to treat acute lymphoblastic leukemia. Two patients had malformations of cortical development. CSF analysis (n = 5) showed a mild elevation in the protein level without other abnormalities. Autoantibody determinations in the serum (n = 4) or the CSF (n = 5) and genetic testing (n = 5) were negative. At final follow-up, all but 1 patient was disabled and required a caregiver, and none were driving. One patient died of probable sudden unexpected death in epilepsy (SUDEP).

Conclusions

Late-onset LGS represents a rare, treatment-resistant generalized epilepsy that is disabling and may be associated with progressive cognitive impairment. The elevated CSF protein level in our cohort could have been due to high seizure burden but increases the possibility of an inflammatory component to the pathophysiology of this disorder.

Optimizing clobazam treatment in patients with Lennox-Gastaut syndrome

Given the complexities managing Lennox-Gastaut syndrome (LGS)-comorbid conditions, multiple associated seizure types that tend to be refractory to treatment-dosage optimization of antiepileptic drug (AED) treatment is a challenge. In the absence of clinical trial data on optimization of AED dosage in patients with LGS, dose titration is guided by personal experience, anecdotal evidence, and specific patient factors (age, comorbid conditions and medications, seizure types, etc.). The goal of this study was to determine whether a 20% increase in adjunctive clobazam was a reasonable benchmark for improved seizure response in patients with LGS who had responded to adjunctive clobazam treatment during a 12-week lead-in trial. This was a post hoc analysis of data from a long-term, open-label extension (OLE) study, which comprised patients who completed 1 of 2 pivotal clobazam lead-in studies. During the lead-in studies, patients received either placebo or clobazam (0.25, 0.50, or 1.0mg/kg/d) (maximum 40mg/d); during OLE, patients received clobazam up to 2.0mg/kg/d (maximum 80mg/d). The post hoc analysis population comprised patients who had ≥25%, ≥50%, or ≥75% seizure reduction from baseline during lead-in clobazam treatment and ≥12months of follow-up data during OLE. Successful dosage increase (i.e., dosage optimization) was defined as ≥20% clobazam dosage increase from OLE baseline, and improved seizure control from OLE baseline (improvement in seizure responder status, or >50% reduction in total seizure frequency). Patients were stratified by responder status after lead-in treatment (OLE baseline) and by lead-in clobazam dosage received. The findings of the analysis indicated that clobazam dosage increases of ≥20% during long-term treatment improved seizure control >80% of patients with LGS who responded to clobazam during lead-in treatment. Rates of successful dosage increase during OLE were high regardless of lead-in dosage received, with the highest rate of successful dosage increase among patients who received low-dosage clobazam during lead-in. Similarly, rates of successful dose increase were high regardless of lead-in seizure responder category, with the highest rates occurring in patients with the highest (≥75%) lead-in response.

Assessment of treatment patterns and healthcare costs associated with probable Lennox-Gastaut syndrome

Lennox-Gastaut syndrome (LGS) is a chronic and severe form of epilepsy characterized by intractable seizures, cognitive impairment, and abnormal electroencephalogram findings with slow spike-wave complexes. It typically presents before age 8, but symptoms continue into adulthood and require lifelong treatment associated with significant clinical burden. Data on LGS-associated healthcare utilization and costs are limited. In this study we use a claims-based LGS classifier based on random forest methodology to identify patients with probable LGS from the a Medicaid multi-state database and assess its prevalence across the age spectrum, healthcare utilization, treatment patterns, costs, and comorbid conditions. The classifier identified patients with probable LGS across all ages, with up to 8% of 10-year-old patients with epilepsy identified as having probable LGS. The prevalence of probable LGS was lower in older age cohorts, indicating that it may be under-recognized in older patients. Our analysis showed that probable LGS is associated with considerably higher total healthcare and medical costs than non-LGS patients. The costs were generally consistent between age cohorts, suggesting that the cost burden extends beyond childhood and has a lifelong impact. Analysis of treatment patterns suggest that while the majority of probable LGS patients in this study received widest-spectrum AEDs, a considerable proportion did not and therefore may have been inadequately treated. Further, usage of clobazam and rufinamide was decreased in older compared to younger patient cohorts, indicating that older patient cohorts are less likely to be receiving optimum treatment for LGS. These findings indicate the need for increased clinical attention to LGS beyond pediatric years, with a focus on optimization of treatment for LGS patients of all ages with widest-spectrum AEDs. Timely recognition and adequate treatment of LGS are likely to result in improved outcomes and less costly management of this condition.