Final results from a Phase 3, long-term, open-label, repeat-dose safety study of diazepam nasal spray for seizure clusters in patients with epilepsy

Safety and effectiveness of diazepam nasal spray in male and female patients: Post hoc analysis of data from a phase 3 safety study

Sex differences in drug pharmacokinetics include variations in the expression of the cytochrome P450 enzymes, which are involved in the metabolism of benzodiazepines. It is unclear whether sex influences outcomes associated with intranasally administered drugs. A post hoc analysis of sex differences was conducted to evaluate the effectiveness and safety of diazepam nasal spray, which included examining changes in the number of days between seizure clusters over time (SEIzure interVAL [SEIVAL]). Diazepam nasal spray is approved for acute treatment of seizure clusters in patients with epilepsy aged ≥6 years. Data from a phase 3 safety study were used to determine the proportion of second doses used within 24 h (ie, a proxy for effectiveness) and SEIVAL. Adverse events were recorded. Of 163 treated patients, 89 were female, and 74 were male. Approximately 16% of both sexes self-administered the study drug. A slightly higher proportion of seizure clusters was treated with a second dose in female (14.7%) than male (9.4%) patients. SEIVAL increased significantly and substantially over a year for all patients. The safety profile was generally similar between the sexes. These results suggest that potential sex differences in benzodiazepine pharmacokinetics do not meaningfully influence outcomes associated with diazepam nasal spray. PLAIN LANGUAGE SUMMARY: Some drugs may have differences in absorption and metabolism between genders that could translate into differences in safety and effectiveness. This safety study looked at diazepam nasal spray for treating seizure clusters in patients at least 6 years old. It found that safety was about the same for females and males. For both groups, most clusters stopped after only 1 dose of the drug, and the time between treated clusters got longer over a year.

Analysis of seizure-cluster circadian periodicity from a long-term, open-label safety study of diazepam nasal spray

OBJECTIVE

Seizure clusters require prompt medical treatment to minimize possible progression to status epilepticus, increased health care use, and disruptions to daily life. Isolated seizures may exhibit cyclical patterns, including circadian and longer rhythms. However, little is known about the cyclical patterns in seizure clusters. This post hoc analysis of data from a long-term, phase 3, open-label, repeat-dose safety study of diazepam nasal spray modeled the periodicity of treated seizure clusters.

METHODS

Mixed-effects cosinor analysis evaluated circadian rhythmicity, and single component cosinors using 12 and 24 h were used to calculate cosinor parameters (e.g., midline statistic of rhythm, wave ampitude, and acrophase [peak]). Analysis was completed for the full cohort and a consistent cohort of participants with two or more seizure clusters in each of four, 3-month periods. The influence of epilepsy type on cosinor parameters was also analyzed.

RESULTS

Seizure-cluster events plotted across 24 h showed a bimodal distribution with acrophases (peaks) at ~06:30 and ~18:30. A 12-h plot showed a single peak at ~06:30. Cosinor analyses of the full and consistent cohort aligned, with acrophases for both models predicting peak seizure activity at ~23:30 on a 24-h scale and ~07:30 on a 12-h scale. The consistent cohort was associated with increases in baseline and peak seizure-cluster activity. Analysis by epilepsy type identified distinct trends. Seizure clusters in the focal epilepsy group peaked in the evening (acrophase 19:19), whereas events in the generalized epilepsy group peaked in the morning (acrophase 04:46). Together they compose the bimodal clustering observed over 24 h.

SIGNIFICANCE

This analysis of seizure clusters treated with diazepam nasal spray demonstrated that seizure clusters occur cyclically in 12- and 24-h time frames similar to that reported with isolated seizures. Further elucidation of these patterns may provide important information for patient care, ranging from improved patient-centered outcomes to seizure-cluster prediction.

Intranasal administration of antiseizure medications in chronic and emergency treatment: Hopes and challenges

Despite the availability of many antiseizure medications (ASMs), 30 % of patients experience pharmacoresistant seizures. High-throughput screening methods undoubtedly remain one of the most important approaches for discovering new molecules to treat seizures. However, the costly and time-consuming nature of drug development prompts us to explore alternative strategies to counteract drug-resistant seizures. One such approach is to consider intranasal administration of known molecules for seizure treatment. In the case of treating epileptic seizures, administering ASMs intranasally may enhance treatment effectiveness and minimize adverse effects. A good example of changes in drug administration is the intranasal administration of fentanyl, which has become a clinical standard in the emergency setting to treat moderate to severe pain in adults and children. This review discusses the utilization of intranasally administered ASMs for both acute and chronic seizures. It addresses various targeted pharmacokinetic approaches, challenges and prospects associated with these regimens. Brief neuroanatomical and molecular rationale for nose-to-brain drug transport is also presented. Furthermore, recent preclinical studies validating the efficacy and brain distribution following intranasal administration of the most commonly used drugs in chronic treatment are also discussed.

Intracerebral electrographic activity following a single dose of diazepam nasal spray: A pilot study

OBJECTIVE

Rescue benzodiazepine medication can be used to treat seizure clusters, which are intermittent, stereotypic episodes of frequent seizure activity that are distinct from a patient's usual seizure pattern. The NeuroPace RNS® System is a device that detects abnormal electrographic activity through intracranial electrodes and administers electrical stimulation to control seizures. Reductions in electrographic activity over days to weeks have been associated with the longer-term efficacy of daily antiseizure medications (ASMs). In this pilot study, electrographic activity over hours to days was examined to assess the impact of a single dose of a proven rescue therapy (diazepam nasal spray) with a rapid onset of action.

METHODS

Adult volunteers (>18 years old) with clinically indicated RNS (stable settings and ASM usage) received a weight-based dose of diazepam nasal spray in the absence of a clinical seizure. Descriptive statistics for a number of detections and a sum of durations of detections at 10-min, hourly, and 24-h intervals during the 7-day (predose) baseline period were calculated. Post-dose detections at each time interval were compared with the respective baseline-detection intervals using a 1 SD threshold. The number of long episodes that occurred after dosing also were compared with the baseline.

RESULTS

Five participants were enrolled, and four completed the study; the excluded participant had recurrent seizures during the study. There were no consistent changes (difference >1 SD) in detections between post-dose and mean baseline values. Although variability was high (1 SD was often near or exceeded the mean), three participants showed possible trends for reductions in one or more electrographic variables following treatment.

SIGNIFICANCE

RNS-assessed electrographic detections and durations were not shown to be sensitive measures of short-term effects associated with a single dose of rescue medication in this small group of participants. The variability of detections may have masked a measurable drug effect.

PLAIN LANGUAGE SUMMARY

Rescue drugs are used to treat seizure clusters. Responsive neurostimulation (RNS) devices detect and record epilepsy brain waves and then send a pulse to help stop seizures. This pilot study looked at whether one dose of a rescue treatment changes brain activity detected by RNS. There was a very wide range of detections, which made it difficult to see if or how the drug changed brain activity. New studies should look at other types of brain activity, multiple doses, and larger patient groups.

Benzodiazepines for the Treatment of Seizure Clusters

Patients with epilepsy may experience seizure clusters, which are described by the US Food and Drug Administration (FDA) as intermittent, stereotypic episodes of frequent seizure activity that are distinct from a patient's usual seizure pattern. Untreated seizure clusters may increase the risk for status epilepticus, as well as decrease quality of life and increase burden on patients and care partners. Benzodiazepine therapies are the mainstay for acute treatment of seizure clusters and are often administered by nonmedical care partners outside a healthcare facility. Three rescue therapies are currently FDA-approved for this indication, with diazepam rectal gel being the first in 1997, for patients aged ≥  2 years. Limitations of rectal administration (e.g., positioning and disrobing the patient, which may affect ease of use and social acceptability; interpatient variation in bioavailability) led to the investigation of the potential for nasal administration as an alternative. Midazolam nasal spray (MDS) was approved by the FDA in 2019 for patients aged ≥  12 years and diazepam nasal spray (DNS) in 2020 for patients aged ≥  6 years; these two intranasal therapies have differences in their formulations [e.g., organic solvents (MDS) vs. Intravail and vitamin E for absorption and solubility (DNS)], effectiveness (e.g., proportion of seizure clusters requiring only one dose), and safety profiles. In clinical studies, the proportion of seizure clusters for which only one dose of medication was used varied between the three approved rescue therapies with the highest single-dose rate for any time period for DNS; however, although studies for all three preparations enrolled patients with highly intractable epilepsy, inclusion and exclusion criteria varied, so the three cannot be directly compared. Treatments that have been used off-label for seizure clusters in the USA include midazolam for injection as an intranasal spray (indicated for sedation/anxiolysis/amnesia and anesthesia) and tablet forms of clonazepam (indicated for treatment for seizure disorders) and lorazepam (indicated for anxiety). In the European Union, buccal and intranasal midazolam are used for treating the indication of prolonged, acute convulsive seizures and rectal diazepam solution for the indication of epileptic and febrile convulsions; duration of effectiveness for these medications for the treatment of seizure clusters has not been established. This paper examines the literature context for understanding seizure clusters and their treatment and provides effectiveness, safety, and administration details for the three FDA-approved rescue therapies. Additionally, other medications that are used for rescue therapy in the USA and globally are discussed. Finally, the potential benefits of seizure action plans and candidates for their use are addressed. This paper is intended to provide details about the unique characteristics of rescue therapies for seizure clusters to help clarify appropriate treatment for individual patients.

Nanotechnology for enhanced nose-to-brain drug delivery in treating neurological diseases

Despite the increasing global incidence of brain disorders, achieving sufficient delivery towards the central nervous system (CNS) remains a formidable challenge in terms of translating into improved clinical outcomes. The brain is highly safeguarded by physiological barriers, primarily the blood-brain barrier (BBB), which routinely excludes most therapeutics from entering the brain following systemic administration. Among various strategies investigated to circumvent this challenge, intranasal administration, a noninvasive method that bypasses the BBB to allow direct access of drugs to the CNS, has been showing promising results. Nanotechnology-based drug delivery systems, in particular, have demonstrated remarkable capacities in overcoming the challenges posed by nose-to-brain drug delivery and facilitating targeted drug accumulation within the brain while minimizing side effects of systemic distribution. This review comprehensively summarizes the barriers of nose-to-brain drug delivery, aiming to enhance our understanding of potential physiological obstacles and improve the efficacy of nasal delivery in future trials. We then highlight cutting-edge nanotechnology-based studies that enhance nose-to-brain drug delivery in three key aspects, demonstrating substantial potential for improved treatment of brain diseases. Furthermore, the attention towards clinical studies will ease the regulatory approval process for nasal administration of nanomedicines targeting brain disease.

Opportunities for Community Pharmacists to Counsel Patients With Epilepsy and Seizure Clusters to Overcome Barriers and Foster Appropriate Treatment

Some patients with epilepsy experience seizure clusters, which may be defined as 2 or more seizures occurring within 24 hours. Left untreated, seizure clusters increase the risk for physical injury and may progress to status epilepticus, irreversible neurologic injury, and death. Rescue therapy is based on benzodiazepine treatment. Prompt, appropriate use should be specified in patients' individualized seizure action plans. Most seizure clusters occur outside the hospital setting. The ideal rescue therapy allows for easy and quick administration by a nonmedical person, which may minimize the need for intervention by emergency medical personnel or transportation to the hospital. In the 2 decades before the approval of 2 intranasal benzodiazepines in 2019 and 2020, rectal diazepam was the only route of administration approved by the US Food and Drug Administration specifically for seizure clusters. Each of the approved intranasal formulations has a unique profile. Both offer a convenient and socially acceptable route of administration. Recognition of seizure clusters and timing of proper administration are key to successful use of rescue therapy. Pharmacists' counseling plays an important role in reinforcing when and how to appropriately administer rescue therapies and the importance of consistently using rescue treatment when indicated to promote effective management. This review includes resources for pharmacists, patients, and caregivers; reviews currently available treatments; and discusses seizure action plans that support effective treatment of seizure clusters.

Rapid Rescue Treatment with Diazepam Nasal Spray Leads to Faster Seizure Cluster Termination in Epilepsy: An Exploratory Post Hoc Cohort Analysis

INTRODUCTION

Although prompt treatment of status epilepticus is standard of care, the effect of timing of rescue therapy administration for seizure clusters in epilepsy remains unknown. Seizure clusters are a rare but clinically important condition, and benzodiazepines are the cornerstone rescue therapy for seizure clusters in epilepsy. We characterized temporal patterns from a large dataset of treated seizure clusters in the safety study of diazepam nasal spray.

METHODS

This post hoc analysis used timing data of treated seizure clusters recorded by care partners and patients in seizure diaries during a 1-year safety study. Data analysis used time from seizure start to administration of diazepam.

RESULTS

From 4466 observations, 3225 had data meeting criteria for analysis. Overall, median times from seizure start to dose administration, dose administration to seizure termination, and total seizure duration were 2, 3, and 7 min, respectively. In seizure clusters treated in < 5 min (median 1.0 min), median time from dose to seizure termination was 2.0 min, and median total seizure duration was 4.0 min. Among seizure clusters treated in ≥ 5 min (median 10.0 min), median time to seizure termination was 10.0 min, and median total seizure duration was 23.0 min. Previously published safety results reported that over a mean participation of 1.5 years, 82.2% of patients had ≥ 1 treatment-emergent adverse events (TEAEs) irrespective of relationship to treatment, including 30.7% with serious TEAEs; 18.4% had TEAEs deemed at least possibly related to the study drug, none of which were serious. There were no events of cardiorespiratory depression.

CONCLUSION

Echoing the importance of early use of benzodiazepines in status epilepticus, the findings from this exploratory analysis of patients with refractory epilepsy and frequent seizure clusters identify a potential benefit of early diazepam nasal spray treatment leading to faster seizure resolution within the seizure cluster. Trial Registration Information: ClinicalTrials.gov identifier NCT02721069 ( https://clinicaltrials.gov/ct2/show/NCT02721069 ).

Analyses of patients who self-administered diazepam nasal spray for acute treatment of seizure clusters

For acute treatment of seizure clusters in patients with epilepsy, intranasal administration of acute seizure therapies has been shown to provide accessibility and ease of use to care partners as well as the potential for self-administration by patients. Diazepam nasal spray (Valtoco®) was approved by the US Food and Drug Administration for acute treatment of intermittent, stereotypic episodes of frequent seizure activity (ie, seizure clusters, acute repetitive seizures) in patients with epilepsy aged ≥6 years. Self-administration consistent with the prescribing information is feasible and was reported by a subgroup of patients (n = 27 of 163) in a long-term phase 3 safety study. Data regarding self-administration among these patients with seizure clusters are examined here to explore the safety profiles and measures of effectiveness, as well as the quality of life of those who self-treated. In addition, this focused look at patients who self-administered diazepam nasal spray may offer some insights into the characteristics of patients who may be appropriate for self-administration.

Practical Questions About Rescue Medications for Acute Treatment of Seizure Clusters in Children and Adolescents with Epilepsy in the USA: Expanding Treatment Options to Address Unmet Needs

Epilepsy is a common pediatric neurological condition, affecting approximately 470,000 children in the USA and having a prevalence of 0.9% in the global population of approximately 2.6 billion children. Epilepsy is associated with disruptions in several areas of a child's life, including medical burden, quality of life, cognitive outcomes, and higher risk of mortality. Additionally, some pediatric patients may experience acute seizure emergencies such as seizure clusters (also called acute repetitive seizures), which are intermittent increases in seizure activity that differ from the patient's usual seizure pattern and may occur despite daily antiseizure drug administration. Seizure clusters increase a patient's risk for status epilepticus and emergency room visits. Benzodiazepines are the main category of drugs used as acute seizure therapies for seizure clusters. This narrative review provides a practical discussion of care for pediatric patients with epilepsy and seizure clusters exploring such topics as details about the US Food and Drug Administration-approved acute seizure therapies, safety and ease of use of these medications, benefits of seizure action plans to help ensure optimal treatment, and considerations for transitioning a pediatric patient with acute seizure therapy to adult healthcare management.

Treatment of Seizure Clusters in Epilepsy: A Narrative Review on Rescue Therapies

Epilepsy is a common neurological disorder in the United States, affecting approximately 1.2% of the population. Some people with epilepsy may experience seizure clusters, which are acute repetitive seizures that differ from the person's usual seizure pattern. Seizure clusters are unpredictable, are emotionally burdensome to patients and caregivers (including care partners), and require prompt treatment to prevent progression to serious outcomes, including status epilepticus and associated morbidity (e.g., lacerations, fractures due to falls) and mortality. Rescue medications for community use can be administered to terminate a seizure cluster, and benzodiazepines are the cornerstone of rescue treatment. Despite the effectiveness of benzodiazepines and the importance of a rapid treatment approach, as many as 80% of adult patients do not use rescue medication to treat seizure clusters. This narrative review provides an update on rescue medications used for treatment of seizure clusters, with an emphasis on clinical development and study programs for diazepam rectal gel, midazolam nasal spray, and diazepam nasal spray. Results from long-term clinical trials have shown that treatments for seizure clusters are effective. Intranasal benzodiazepines provide ease of use and patient and caregiver satisfaction in pediatric and adult patients. Adverse events attributed to acute rescue treatments have been characterized as mild to moderate, and no reports of respiratory depression have been attributed to treatment in long-term safety studies. The implementation of an acute seizure action plan to facilitate optimal use of rescue medications provides an opportunity for improved management of seizure clusters, allowing those affected to resume normal daily activities more quickly.

Brain-Derived Neurotrophic Factor Dysregulation as an Essential Pathological Feature in Huntington's Disease: Mechanisms and Potential Therapeutics

Brain-derived neurotrophic factor (BDNF) is a major neurotrophin whose loss or interruption is well established to have numerous intersections with the pathogenesis of progressive neurological disorders. There is perhaps no greater example of disease pathogenesis resulting from the dysregulation of BDNF signaling than Huntington's disease (HD)-an inherited neurodegenerative disorder characterized by motor, psychiatric, and cognitive impairments associated with basal ganglia dysfunction and the ultimate death of striatal projection neurons. Investigation of the collection of mechanisms leading to BDNF loss in HD highlights this neurotrophin's importance to neuronal viability and calls attention to opportunities for therapeutic interventions. Using electronic database searches of existing and forthcoming research, we constructed a literature review with the overarching goal of exploring the diverse set of molecular events that trigger BDNF dysregulation within HD. We highlighted research that investigated these major mechanisms in preclinical models of HD and connected these studies to those evaluating similar endpoints in human HD subjects. We also included a special focus on the growing body of literature detailing key transcriptomic and epigenetic alterations that affect BDNF abundance in HD. Finally, we offer critical evaluation of proposed neurotrophin-directed therapies and assessed clinical trials seeking to correct BDNF expression in HD individuals.

Optimizing Absorption for Intranasal Delivery of Drugs Targeting the Central Nervous System Using Alkylsaccharide Permeation Enhancers

Intranasal delivery of drugs offers several potential benefits related to ease of delivery, rapid onset, and patient experience, which may be of particular relevance to patients with central nervous system (CNS) conditions who experience acute events. Intranasal formulations must be adapted to address anatomical and physiological characteristics of the nasal cavity, including restricted dose volume, limited surface area, and barriers to mucosal absorption, in addition to constraints on the absorption window due to mucociliary clearance. Development of an effective formulation may utilize strategies including the addition of excipients to address the physicochemical properties of the drug within the constraints of nasal delivery. Dodecyl maltoside (DDM) and tetradecyl maltoside are alkylsaccharide permeation enhancers with well-established safety profiles, and studies have demonstrated transiently improved absorption and favorable bioavailability of several compounds in preclinical and clinical trials. Dodecyl maltoside is a component of three US Food and Drug Administration (FDA)-approved intranasal medications: diazepam for the treatment of seizure cluster in epilepsy, nalmefene for the treatment of acute opioid overdose, and sumatriptan for the treatment of migraine. Another drug product with DDM as an excipient is currently under FDA review, and numerous investigational drugs are in early-stage development. Here, we review factors related to the delivery of intranasal drugs and the role of alkylsaccharide permeation enhancers in the context of approved and future intranasal formulations of drugs for CNS conditions.

Acute seizure therapies in people with epilepsy: Fact or fiction? A U.S. Perspective

Patients with epilepsy (PWE) may experience seizure emergencies including acute repetitive seizures despite chronic treatment with daily antiseizure medications. Seizures may adversely impact routine daily activities and/or healthcare utilization and may impair the quality of life of patients with epilepsy and their caregivers. Seizures often occur at home, school, or work in a community setting. Appropriate treatment that is readily accessible for patients with seizure urgencies and emergencies is essential outside the hospital setting. When determining the best acute antiseizure therapy for PWE, clinicians need to consider all of the available rescue medications and their routes of administration including the safety and efficacy profiles. Benzodiazepines are a standard of care as a rescue therapy, yet there are several misconceptions about their use and safety. Reevaluating potential misconceptions and formulating best practices are necessary to maximize usage for each available option of acute therapy. We examine common beliefs associated with traditional use of acute seizure therapies to refute or support them based on the current level of evidence in the published literature.

Acute Abortive Therapies for Seizure Clusters in Long-Term Care

OBJECTIVES

To describe acute seizure treatment for the long-term care setting, emphasizing rescue (acute abortive) medications for on-site management of acute unexpected seizures and seizure clusters.

DESIGN

Narrative review.

SETTING AND PARTICIPANTS

People with seizures in long-term care, including group residences.

METHODS

PubMed was searched using keywords that pertained to rescue medications, seizure emergencies/epilepsy, seizure action plans, and long-term care.

RESULTS

Seizure disorder, including epilepsy, is prevalent in long-term care residences, and rescue medications can be used for on-site treatment. Diazepam rectal gel, intranasal midazolam, and diazepam nasal spray are US Food and Drug Administration (FDA)-approved seizure-cluster rescue medications, and intravenous diazepam and lorazepam are approved for status epilepticus. Benzodiazepines differ by formulation, route of administration, absorption, and metabolism. Intranasal formulations are easy and ideal for public use and when rectal treatment is challenging (eg, wheelchair). Intranasal, intrabuccal, and rectal formulations do not require specialized training to administer and are easier for staff at all levels of training compared with intravenous treatment. Off-label rescue medications may have anecdotal support; however, potential disadvantages include variable absorption and onset of action as well as potential risks to patients and caregivers/care partners. Delivery of intravenous-administered rescue medications is delayed by the time needed to set up and deliver the medication and is subject to dosing errors. Seizure action plans that include management of acute seizures can optimize the quality and timing of treatment, which may reduce emergency service needs and prevent progression to status epilepticus.

CONCLUSIONS AND IMPLICATIONS

Seizure disorder is prevalent across all ages but is increased in older adults and in those with intellectual and developmental disabilities. Prompt intervention may reduce negative outcomes associated with acute unexpected seizures and seizure clusters. Seizure action plans that include acute seizures can improve the treatment response by detailing the necessary information for staff to provide immediate treatment.

Concomitant cannabidiol does not impact safety and effectiveness of diazepam nasal spray for seizure clusters: Post hoc analysis of a phase 3 safety study

People with epilepsy may experience episodes of frequent seizure activity (seizure clusters, acute repetitive seizures), and benzodiazepines are the cornerstone of rescue treatment. Cannabidiol (CBD) can be used as an adjunctive treatment for epilepsy, and it may interact with other antiseizure drugs, such as benzodiazepines. Here, we examined the safety and effectiveness of intermittent use of diazepam nasal spray in patients with seizure clusters who also received CBD treatment. This analysis included data from patients aged 6 to 65 years enrolled in a phase 3, long-term safety study of diazepam nasal spray. Age- and weight-based dosing of diazepam nasal spray were administered during a 12-month treatment period. Concomitant CBD use was recorded, and treatment-emergent adverse events (TEAEs) were collected. Of 163 treated patients, 119 (73.0%) did not receive CBD, 23 (14.1%) received the US Food and Drug Administration-approved highly purified CBD and 21 (12.9%) received another form of CBD. On average, patients receiving highly purified CBD were younger and more likely to have epileptic encephalopathies, including Dravet syndrome or Lennox-Gastaut syndrome, than patients who received another CBD preparation or no CBD. Rates of TEAEs and serious TEAEs were greater in patients who received any form of CBD (90.9% and 45.5%, respectively) compared with no CBD (79.0% and 26.1%, respectively). However, the lowest rates of TEAEs attributed to diazepam nasal spray were reported in patients who received highly purified CBD (13.0%), and this result was maintained in those who received concomitant clobazam. Use of second doses of diazepam nasal spray, a proxy for effectiveness, was lowest in the highly purified-CBD group (8.2%) compared with the no-CBD (11.6%) and other-CBD groups (20.3%). These results suggest that CBD does not alter the safety and effectiveness of diazepam nasal spray and supports concomitant use in appropriate patients.

Overcoming barriers to the management of seizure clusters: ease of use and time to administration of rescue medications

INTRODUCTION

Patients with epilepsy can experience seizure clusters (acute repetitive seizures), defined as intermittent, stereotypic episodes of frequent seizure activity that are distinct from typical seizure patterns. There are three FDA-approved rescue medications, diazepam rectal gel, midazolam nasal spray, and diazepam nasal spray, that can be administered to abort a seizure cluster in a nonmedical, community setting. Despite their effectiveness and safety, rescue medications are underutilized, and patient/caregiver experiences and perceptions of ease of use may constitute a substantial barrier to greater utilization.

AREAS COVERED

The literature on rescue medications for seizure clusters is reviewed, including the effectiveness and safety, with an emphasis on ease and timing of treatment and associated outcomes. Barriers to greater utilization of rescue medication and the role of seizure action plans are discussed.

EXPERT OPINION

Intranasal rescue medications are easier to use and can be administered more rapidly than other routes (rectal, intravenous). Importantly, rapid administration of intranasal rescue medications has been associated with shorter durations of seizure activity as compared with rectal/intravenous routes. Intranasal rescue medications are also easy to use and socially acceptable. These factors potentially remove or reduce barriers to use and optimize the management of seizure clusters.

Safety of Diazepam Nasal Spray in Pediatric Patients With Developmental Epileptic Encephalopathies: Results From a Long-term Phase 3 Safety Study

Pediatric developmental epileptic encephalopathies are often refractory to treatment despite stable antiseizure therapy. The safety profile of diazepam nasal spray (Valtoco) as rescue therapy for seizure clusters was described in a long-term safety study. This post hoc analysis assessed safety and effectiveness within a subpopulation of patients with developmental epileptic encephalopathies. Of 163 treated patients, 64 were diagnosed with ≥1 pediatric developmental epileptic encephalopathy. Among the most common developmental epileptic encephalopathies were Rett syndrome (n = 16), Lennox-Gastaut syndrome (n = 9), and Dravet syndrome (n = 7). In the broad pediatric developmental epileptic encephalopathy group, 10.6% of seizure clusters were treated with a second dose, with similar proportions in the 3 individual encephalopathies. Across groups, treatment-emergent adverse event rates ranged from 66.7% to 100%. Only epistaxis (n = 2) was treatment-related and reported in >1 patient. In this long-term safety analysis in patients with developmental epileptic encephalopathies, diazepam nasal spray demonstrated a consistent safety profile, supporting its use in these hard-to-treat patients (ClinicalTrials.gov NCT02721069).

A retrospective multicentric study on the effectiveness of intravenous brivaracetam in seizure clusters: Data from the Italian experience

OBJECTIVE

Nearly half of people with epilepsy (PWE) are expected to develop seizure clusters (SC), with the subsequent risk of hospitalization. The aim of the present study was to evaluate the use, effectiveness and safety of intravenous (IV) brivaracetam (BRV) in the treatment of SC.

METHODS

Retrospective multicentric study of patients with SC (≥ 2 seizures/24 h) who received IV BRV. Data collection occurred from January 2019 to April 2022 in 25 Italian neurology units. Primary efficacy outcome was seizure freedom up to 24 h from BRV administration. We also evaluated the risk of evolution into Status Epilepticus (SE) at 6, 12 and 24 h after treatment initiation. A Cox regression model was used to identify outcome predictors.

RESULTS

97 patients were included (mean age 62 years), 74 (76%) of whom had a history of epilepsy (with drug resistant seizures in 49% of cases). BRV was administered as first line treatment in 16% of the episodes, while it was used as first or second drug after benzodiazepines failure in 49% and 35% of episodes, respectively. On the one hand, 58% patients were seizure free at 24 h after BRV administration and no other rescue medications were used in 75 out of 97 cases (77%) On the other hand, SC evolved into SE in 17% of cases. A higher probability of seizure relapse and/or evolution into SE was observed in patients without a prior history of epilepsy (HR 2.0; 95% CI 1.03 - 4.1) and in case of BRV administration as second/third line drug (HR 3.2; 95% CI 1.1 - 9.7). No severe treatment emergent adverse events were observed.

SIGNIFICANCE

In our cohort, IV BRV resulted to be well tolerated for the treatment of SC and it could be considered as a treatment option, particularly in case of in-hospital onset. However, the underlying etiology seems to be the main outcome predictor.

Seizure Rescue Therapies: Comparing Approved and Commonly Used Benzodiazepine Formulations

Acute seizure therapies given out of the hospital are important for interrupting acute repetitive and prolonged seizures and preventing hospitalization. These vary in their administration routes, indications for children and adults, pharmacologic profiles, and efficacy. We reviewed and compared the uses of current formulations available to treat acute seizures, including newly released intranasal (IN) benzodiazepines and older formulations which are widely used for interrupting seizures.

Recent advances in pharmacotherapy for epilepsy

PURPOSE OF REVIEW

Epilepsy affects 70 million people worldwide and is a significant cause of morbidity and early mortality. The mainstay of therapy is oral medications. Epilepsy drug development is escalating, driven by continued drug resistance in up to a third of epilepsy patients. Treatment development now focuses on discovery of novel mechanisms of action and syndrome-specific therapies.

RECENT FINDINGS

Difficult-to-treat epilepsy related to conditions including tuberous sclerosis complex (TSC), Lennox Gastaut syndrome (LGS) and Dravet syndrome (DS) have been the target of recent developments. Disease-modifying therapy for epilepsy related to TSC with vigabatrin at onset of first electroencephalographic epileptiform changes, rather than after first clinical seizure, has demonstrated strongly positive seizure and developmental outcomes. Fenfluramine, approved for DS and, more recently, LGS, has robust data supporting efficacy, safety/tolerability, as well as mortality, quality of life and cognitive function. Rescue therapy has expanded to include better tolerated benzodiazepines in the form of nasal midazolam and valium. Cenobamate, a first-in-class inactivator of the persistent voltage-gated sodium channel and approved for adult partial onset epilepsy, has exceptional efficacy and tolerability and will be expanded to children and to generalized onset epilepsy in adults.

SUMMARY

The repertoire of available and developmental therapies for epilepsy is rapidly expanding, and now includes disease-modifying vigabatrin in TSC and agents with extraordinary efficacy, fenfluramine and cenobamate.

Epilepsy care in nursing facilities: Knowledge gaps and opportunities

Epilepsy in the elderly is a complex disease, often underdiagnosed, and inadequately treated. It requires a multi-disciplinary approach and care coordination especially if the patient resides in a nursing facility. Episodes of loss of consciousness falls, or amnestic events in those living in a nursing facility require a detailed description and an urgent assessment to rule out an epileptic seizure. Prompt recognition of seizures and the implementation of treatment protocols in those with recurrent seizures are needed to prevent unnecessary emergency visits. Although there is a myriad of antiseizure medications (ASM) to treat seizures, clinicians should be aware of common interactions, side effects, and changes in pharmacodynamics with age. There is a limited number of ASMs that have been properly studied in clinical trials to assess tolerability and efficacy in the elderly, and an over-reliance on enzyme-inducing ASMs. Strategies to improve the knowledge of health care providers include electronic resources, treatment protocols, and improving awareness of the efficacy, drug-drug interaction, and short-term and long-term monitoring of ASM side effects.

The nose has it: Opportunities and challenges for intranasal drug administration for neurologic conditions including seizure clusters

Nasal administration of treatments for neurologic conditions, including rescue therapies to treat seizure clusters among people with epilepsy, represents a meaningful advance in patient care. Nasal anatomy and physiology underpin the multiple advantages of nasal administration but also present challenges that must be addressed in any successful nasal formulation. Nasal cavity anatomy is complex, with a modest surface area for absorption that limits the dose volume of an intranasal formulation. The mucociliary clearance mechanism and natural barriers of the nasal epithelia must be overcome for adequate absorption. An extensive vasculature and the presence of olfactory nerves in the nasal cavity enable both systemic and direct-to-brain delivery of drugs targeting the central nervous system. Two intranasal benzodiazepine rescue therapies have been approved by the US Food and Drug Administration for seizure-cluster treatment, in addition to the traditional rectal formulation. Nasal sprays are easy to use and offer the potential for quick and consistent bioavailability. This review aims to increase the clinician's understanding of nasal anatomy and physiology and of the formulation of intranasal rescue therapies and to facilitate patient education and incorporate intranasal rescue therapies for seizure clusters (also known as acute repetitive seizures) into their seizure action plans.

Prevalence and Predictors of Seizure Clusters in Pediatric Patients With Epilepsy: The Harvard-Yale Pediatric Seizure Cluster Study

BACKGROUND

Determine the prevalence of seizure clusters (two or more seizures in six hours), use of rescue medications, and adverse outcomes associated with seizure clusters in pediatric patients with a range of epilepsy severities, and identify risk factors predictive of seizure clusters.

METHODS

Prospective observational two-center study, including phone call and seizure diary follow-up for 12 months in patients with epilepsy aged one month to 18 years. We classified patients into three risk groups based on seizures within the prior year: high, seizure cluster (two or more seizures within one day); intermediate, at least one seizure but no days with two or more seizures; low, no seizures.

RESULTS

One-third (32.3%; high risk, 72.4%; intermediate risk, 30.4%; low risk, 3.1%) of 297 patients had a seizure cluster during the study, including half (46.2%) of the patients with active seizures at baseline (intermediate- and high-risk groups combined). Emergency room visits or injuries were no more likely due to a seizure cluster than an isolated seizure. Rescue medications were utilized in 15.8% of patients in the high-risk group and 19.2% in the intermediate-risk group. History of status epilepticus (adjusted odds ratio [aOR], 2.13; confidence interval [CI], 1.09 to 4.16]), seizure frequency greater than four per month (aOR, 4.27; CI, 1.92 to 9.50), and high-risk group status (aOR, 6.42; CI, 2.97 to 13.87) were associated with greater odds of seizure cluster.

CONCLUSIONS

Seizure clusters are common in pediatric patients with epilepsy. High seizure frequency was the strongest predictor of clusters. Rescue medications were underutilized. Future studies should evaluate the applicability and effectiveness of these medications for optimization of pediatric seizure cluster treatment and reduction of seizure-related emergency department visits, injuries, and mortality.

Seizure rescue medications are missing from in-flight medical emergency kits

OBJECTIVE

We aimed to inquire whether any seizure rescue medications are included in the in-flight medical emergency kits of the main airlines in the world. This data could help the airline authorities update their strategies in light of any shortcomings.

METHODS

First, we identified ten major airlines in the world. Then, we searched the Google engine with the following keywords: "name of the airline" and "in-flight medical emergency" or "first aid kit" or "emergency kit". In case there was no information on the web, we emailed the airlines and inquired about the contents of their in-flight medical emergency kits. We also investigated some of the major aviation organizations' websites [i.e., Aerospace Medical Association (AsMA), International Civil Aviation Organization (ICAO), and International Air Transport Association (IATA)].

RESULTS

None of the major airlines were equipped with easily applicable seizure rescue medications (i.e., buccal midazolam, a nasal spray of midazolam, or intranasal diazepam). The AsMA and ICAO recommend including injectable sedative anticonvulsant drugs in the in-flight medical emergency kits without any further specifications. The IATA does not provide specific recommendations for including seizure rescue medications in the in-flight medical emergency kits.

CONCLUSION

A seizure is a significant in-flight medical emergency event. The use of easily applicable seizure rescue medications during prolonged or repeated seizures is significantly associated with fewer sequelae for the affected person. Easily applicable seizure rescue medications should be included in the in-flight medical emergency kits, and the cabin crew should receive training on how and when to use them.

A bibliometric analysis of the recent advances in diazepam from 2012 to 2021

Background: Diazepam is a classic benzodiazepine drug that has been widely used for disorders such as anxiety, sleep disorders, and epilepsy, over the past 59 years. The study of diazepam has always been an important research topic. However, there are few bibliometric analyses or systematic studies in this field. This study undertook bibliometric and visual analysis to ascertain the current status of diazepam research, and to identify research hotspots and trends in the past 10 years, to better understand future developments in basic and clinical research.

Methods: Articles and reviews of diazepam were retrieved from the Web of Science core collection. Using CiteSpace, VOSviewer, and Scimago Graphica software, countries, institutions, authors, journals, references, and keywords in the field were visually analyzed.

Results: A total of 3,870 publications were included. Diazepam-related literature had high volumes of publications and citations. The majority of publications were from the USA and China. The highest number of publications and co-citations, among the authors, was by James M Cook. Epilepsia and the Latin American Journal of Pharmacy were the journals with the most publications on diazepam and Epilepsia was the most frequently cited journal. Through a comprehensive analysis of keywords and references, we found that current research on diazepam has focused on its mechanism of action, application in disease, pharmacokinetics, risk, assessment, and management of use, status epilepticus, gamma-aminobutyric acid receptors (GABAR), intranasal formulation, gephyrin, and that ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) is the current research hotspot.

Conclusion: Research on diazepam is flourishing. We identified research hotspots and trends in diazepam research using bibliometric and visual analytic methods. The clinical applications, mechanisms of action, pharmacokinetics, and assessment and management of the use of diazepam are the focus of current research and the development trend of future research.

Significant improvements in SEIzure interVAL (time between seizure clusters) across time in patients treated with diazepam nasal spray as intermittent rescue therapy for seizure clusters

OBJECTIVE

Intermittent rescue therapy may be used for seizure clusters, which are clinical emergencies that may persist ≥24 h and increase risk of status epilepticus, emergency room visits, and reduced quality of life for patients with epilepsy. Beyond effectiveness for aborting seizure clusters, no data exist on how intermittent rescue therapy may impact the long-term natural course of seizure clusters. This novel analysis explores SEIzure interVAL (SEIVAL; time between seizure clusters) in patients from a long-term safety study of diazepam nasal spray (Valtoco) to assess SEIVAL changes with intermittent rescue therapy across time.

METHODS

Patients were aged 6-65 years. Age- and weight-based doses of diazepam nasal spray were administered during a 12-month treatment period with an optional follow-up period. SEIVAL was evaluated in patients receiving two or more doses of diazepam nasal spray using 90-day periods.

RESULTS

Of 163 treated patients, 151 had one or more SEIVALs. One hundred twenty had SEIVALs in Period 1 and one or more other periods. An increase in SEIVAL was noted from Period 1 compared with all subsequent periods (p ≤ .001). A consistent cohort (n = 76) had one or more SEIVALs in each of Periods 1-4 (360 days); mean SEIVALs increased significantly (p < .01) from 12.2 days (Period 1) to 25.7 days (Period 4). Similar SEIVAL patterns occurred when repeat doses within a seizure cluster were eliminated and irrespective of age group, treatment duration, and change to concomitant medications. In adults, Quality of Life in Epilepsy scores were maintained with increased SEIVALs.

SIGNIFICANCE

Across 12 months, increases in SEIVAL were demonstrated in patients using diazepam nasal spray for seizure cluster treatment in a phase 3 safety study. Increased time between seizure clusters may reflect a previously unrecognized beneficial effect of intermittent rescue therapy. These results generate a range of biological and behavioral hypotheses and warrant exploration of the impact of intermittent rescue therapy.

Rescue therapies for seizure clusters: Pharmacology and target of treatments

The primary goal of treatment for seizure clusters is cessation of the cluster to avoid progression to more severe conditions, such as prolonged seizures and status epilepticus. Rescue therapies are key components of treatment plans for patients with seizure clusters. Three rescue therapies are approved in the United States for the treatment of seizure clusters: diazepam rectal gel, midazolam nasal spray, and diazepam nasal spray. This review characterizes the pharmacological function of rescue therapies for seizure clusters, as well as describing γ‐aminobutyric acid A (GABA_A) receptor functions. GABA_A receptors are heteropentamers, consisting primarily of α1‐6, β1‐3, γ2, and δ subunits in the central nervous system. These subunits can traffic to and from the membrane to regulate membrane potential. Benzodiazepines, such as diazepam and midazolam, are positive allosteric modulators of GABA_A receptors, the activation of which leads to an increase in intracellular chloride, hyperpolarization of the cell membrane, and a reduction in excitation. GABA_A receptor subunit mutations, dysregulation of trafficking, and degradation are associated with epilepsy. Although benzodiazepines are effective GABA_A receptor modulators, individual formulations have unique profiles in practice. Diazepam rectal gel is an effective rescue therapy for seizure clusters; however, adults and adolescents may have social reservations regarding its administration. Intranasal delivery of midazolam or diazepam is a promising alternative to rectal administration because these formulations offer easy, socially acceptable administration and exhibit a rapid onset. Off‐label benzodiazepines, such as orally disintegrating lorazepam and intranasal use of an intravenous formulation of midazolam via nasal atomizer, are less well characterized regarding bioavailability and tolerability compared with approved agents.

Use of new intranasal benzodiazepines at a typical adult epilepsy center

OBJECTIVE

The aim of this study was to review out-of-hospital use of intranasal diazepam and midazolam for treatment of acute repetitive seizures (ARS) at a typical adult epilepsy center.

METHODS

Data were collected through chart review and by telephone calls to either the patient or the caregiver regarding drug effectiveness, overall satisfaction, and adverse events.

RESULTS

We identified 96 patients who were prescribed either benzodiazepine. Thirty-nine patients in the diazepam group and 38 patients in the midazolam group were able to be contacted and were included in the study. Sixty-two percent of patients in the diazepam group and 55% of patients in the midazolam group had used the medication at the time of data collection. Of these patients, 83% of patients in the diazepam group and 85% of patients in the midazolam group reported cessation of seizures after either the first or second dose. In comparison of the average patient satisfaction between intranasal diazepam and midazolam, there was no statistical significance (4.25 ± 1.22 vs 3.95 ± 1.35; p = 0.42). Adverse events were minor, included fatigue, nasal discomfort, headache, and dizziness.

DISCUSSION

The use of the two new intranasal benzodiazepines was roughly divided equally. Slightly more than half of the patients who were prescribed the medication had used it. The overall satisfaction of the two medications was comparable. These findings highlight the principal usability of intranasal diazepam and midazolam in adults with ARS.

Economic aspects of treating seizure clusters

Seizure clusters may initiate a chain of events that have economic as well as clinical consequences. The potential economic consequences of seizure clusters must be weighed against the cost of medication to attenuate them. This is true both for individual patients and for society. Data needed for economic analyses include the chance that a cluster will progress to an adverse outcome, such as a need for emergency care, the costs of such an outcome, the cost of a rescue medication (RM), and the effectiveness of the RM. Indirect costs, such as lost employment for patients and caregivers, must also be considered. Several types of economic analyses can be used to determine costs and benefits of a medical intervention. There are studies comparing different RMs from an economic perspective, but there is little direct information on the costs of using an RM versus allowing clusters to run their course. However, the high expense of consequences of seizure clusters makes it likely that effective RMs will make economic as well as medical sense for many patients.

Quality-of-life results in adults with epilepsy using diazepam nasal spray for seizure clusters from a long-term, open-label safety study

BACKGROUND

The impact of seizure clusters and the use of intermittent rescue therapy for clusters on the quality of life (QoL) of patients with epilepsy has not been widely studied. The present analysis assessed QoL as a secondary endpoint among adult patients with seizure clusters enrolled in a long-term, phase 3, open-label safety study (NCT02721069) of diazepam nasal spray (Valtoco®). The QoL aspect of patients in this study has not been previously published.

METHODS

The 12-month safety study of diazepam nasal spray enrolled patients aged 6-65 years with seizure clusters. Adults aged ≥18 years completed the Quality of Life in Epilepsy (QOLIE)-31-P at baseline (day 0) and days 30, 150, 270, and 365. This instrument includes questions about patient health and daily activities with numeric values (1-100) assigned to responses; higher scores indicate better QoL. The QOLIE-31-P includes 7 subscales: Seizure Worry, Overall QoL, Emotional Well-Being, Energy/Fatigue, Cognitive Functioning, Medication Effects, and Social Functioning; an Overall Score is calculated as a weighted composite of the 7 subscales. Comparisons were made between subgroups of patients who had frequent (≥2) and infrequent (<2) monthly dosing of diazepam nasal spray and those whose doses were administered by the patient or a care partner. This safety study was not powered to assess efficacy endpoints; descriptive statistics were calculated across time points. In addition, safety measures, including treatment-emergent adverse events, are reported.

RESULTS

Seventy-two adults who responded to the QOLIE-31-P were included in the analyses. Mean QOLIE-31-P scores were stable or increased across time points. The mean total scores increased from day 0 to day 365 by 5.2 among patients providing data for ≥1 time point (follow-up group) and 2.2 among patients providing data at all time points (QOLIE all-assessments subgroup). Subscale means for Seizure Worry and Social Functioning showed the greatest numeric increase from baseline. Mean QOLIE-31-P scores were similar in all subgroups. The safety profile in the follow-up group was similar to that seen in all study adults.

CONCLUSIONS

Adults with refractory epilepsy who were treated with diazepam nasal spray for seizure clusters maintained or improved QOLIE subscale scores across the 12-month study period. Seizure Worry and Social Functioning subscale scores increased over time, suggesting improvement in these domains for this population with intractable epilepsy. Changes among subscale results suggest differences in sensitivity to the use of an intermittent treatment. The potential to improve patient function with treatment for seizure clusters warrants further study.

Recognizing seizure clusters in the community: The path to uniformity and individualization in nomenclature and definition

Seizure emergencies experienced by patients with epilepsy include status epilepticus and seizure clusters. Although an accepted definition of status epilepticus exists, no clear consensus definition of seizure clusters has emerged; this is further complicated by the appearance in the literature of various empirically based definitions that have been developed for clinical trial study designs. In general, patients with intractable epilepsy have been shown to have a significant risk for acute episodes of increased seizure activity called seizure clusters (also referred to as acute repetitive seizures, among other terms) that differ from their usual seizure pattern. Duration (e.g., number of hours or days) is often included in the definition of a seizure cluster; however, the duration may vary among patients, with some seizure clusters lasting ≥24 h and requiring long-acting treatment for this period. In addition to seizure cluster duration, the time between seizures and possible acceleration in seizure frequency during the cluster may be important variables. The recognition and treatment of seizure clusters require urgent action because episodes that are not quickly and appropriately treated may lead to injury or progress to status epilepticus or potentially death. Most seizure clusters occur outside a medical facility (in the community) and treatment is usually administered by nonmedical individuals; therefore, health care providers may benefit from a clear description of these potential seizure emergencies that they can then use to educate patients and caregivers on the prompt and appropriate identification of seizure clusters and administration of rescue therapy. Here we explore why greater uniformity is needed in the discussion of seizure clusters. This exploration examines epidemiologic studies of seizure clusters and status epilepticus, inconsistencies in nomenclature and definitions for seizure clusters, practical application of seizure cluster terminology, and the potential use of acute seizure action plans and patient-specific individualized definitions in the clinical setting.

Updated review of rescue treatments for seizure clusters and prolonged seizures

INTRODUCTION

Although the treatment of epilepsy primarily focuses on prevention, recurrent seizures are unfortunately an ongoing reality, particularly in people with epilepsy who live with chronic refractory seizures. Rescue medications are agents which can be administered in urgent/emergent seizure episodes such as seizure clusters or prolonged seizures with the goal of terminating seizure activity, preventing morbidity, and decreasing the risk of further seizures.

AREAS COVERED

This review first discusses clinical opportunities for rescue medications, with particular attention focused on seizure clusters and prolonged seizures, including their epidemiology, risk factors, and associated morbidity. Current rescue medications, their indications, efficacy, and adverse effects are discussed. We then discuss rescue medications and formulations which are currently under development, concentrating on practical aspects relevant for clinical care.

EXPERT OPINION

Rescue medications should be considered for all people with epilepsy with ongoing seizures. Recent rescue medications including intranasal formulations provide considerable advantages. New rescue medications are being developed which may expand opportunities for effective treatment. In the future, combining rescue medications with seizure detection and seizure prediction technologies should further expand opportunities for use and should reduce the morbidity of seizures and provide increased comfort, control, and quality of life for people living with epilepsy.

Safety of Diazepam Nasal Spray in Children and Adolescents With Epilepsy: Results From a Long-Term Phase 3 Safety Study

BACKGROUND

To evaluate safety and tolerability of long-term treatment with diazepam nasal spray (Valtoco) for seizure clusters in patients aged six to 17 years.

METHODS

The study enrolled patients aged six to 65 years with frequent seizure clusters. Age- and weight-based doses of diazepam nasal spray were administered; second doses were permitted if needed. Safety assessments included treatment-emergent adverse events (TEAEs).

RESULTS

Of 163 treated patients, 45 (27.6%) were aged six to 11 years and 33 (20.2%) were aged 12 to 17 years. Mean doses per month were 2.1 in the 6 to 11 subgroup and 2.4 in the 12 to 17 subgroup. Of 1634 seizure clusters in pediatric patients, 186 (11.4%) required a second dose of diazepam nasal spray within 24 hours of the first dose. Similar proportions of TEAEs and serious TEAEs were reported in 6 to 11 (91.1%, 40.0%) and 12 to 17 subgroups (81.8%, 30.3%), respectively. No serious TEAEs were considered treatment related, and no patients discontinued because of TEAEs. Treatment-related TEAEs were more frequent in the 12 to 17 subgroup; only epistaxis and somnolence occurred in two or more patients overall. TEAE rates were similar across subgroups that received concomitant clobazam (90.0%), received prior diazepam rectal gel (90.9%), and were administered less than two versus greater than or equal to two doses per month (87.2% for both) of diazepam nasal spray. Most survey respondents (88%) were satisfied or very satisfied with treatment.

CONCLUSIONS

In this long-term safety analysis in pediatric patients with seizure clusters, repeated doses of diazepam nasal spray demonstrated a safety profile consistent across subgroups. These data support the dosing guidelines for diazepam nasal spray according to age and weight for pediatric patients.

Lack of Clinically Relevant Differences in Safety and Pharmacokinetics After Second-Dose Administration of Intranasal Diazepam Within 4 Hours for Acute Treatment of Seizure Clusters: A Population Analysis

Objective

Current diazepam nasal spray labeling requires waiting 4 h before administering a second dose. The objective of the current analyses was to examine safety and pharmacokinetic profiles of second doses of diazepam nasal spray given 0−4 h after the first dose.

Methods

Two datasets were analyzed. The first, a long‐term, repeat‐dose safety study of diazepam nasal spray, compared rates of treatment‐emergent adverse events (TEAEs), serious TEAEs, and treatment‐related TEAEs for patients receiving ≥1 second dose ≤4 h versus all second doses >4 h after the first. The second was a population pharmacokinetic analysis using data from three phase 1 studies to model drug exposure when a second dose of diazepam nasal spray was administered across multiple time points (1 min−4 h) following the first dose.

Results

In the repeat‐dose safety study, a second dose of diazepam nasal spray was administered ≤24 h after the first to treat 485 seizure clusters in 79 patients. Rates of TEAEs were similar between patients receiving ≥1 second dose in ≤4 h (89.5%, n = 38) compared with >4–24 h only (80.5%, n = 41). The most common treatment‐related TEAEs were associated with nasal discomfort, which was mild or moderate and transient. There were no reports of respiratory or cardiac depression. The pharmacokinetic simulations of second doses predicted comparable elevations of plasma diazepam concentrations with administrations across a range of intervals after the first dose (1 min−4 h).

Significance

These data indicate that the safety and pharmacokinetic profiles of a second dose of diazepam nasal spray administered within 4 h of the first dose are consistent with those associated with current labeling. This is potentially important for patients with seizure clusters who have a recurrent seizure within 4 h of first treatment and might benefit from immediate retreatment to reduce the risk of progression to status epilepticus.

Rescue therapies in epilepsy

PURPOSE OF REVIEW

The purpose of this review is to provide a succinct evaluation of the current rescue medications and action plans available to our patients with seizure clusters in the outpatient setting.

RECENT FINDINGS

The main themes of the recent findings are that rescue medications and seizure action plans (SAPs) are underutilized, particularly in the adult population. The safety and efficacy of intranasal midazolam and intranasal diazepam is comparable with rectal diazepam for the treatment of seizure clusters. Additionally, this intranasal formulation has the benefit of a more socially acceptable route of administration and ease of use.

SUMMARY

The implication of these findings is a greater variety and awareness in the rescue medications available to our patients suffering from seizure clusters.

Use of second doses of Valtoco® (diazepam nasal spray) across 24 hours after the initial dose for out-of-hospital seizure clusters: Results from a phase 3, open-label, repeat-dose safety study

Objective

An exploratory analysis from a long‐term, phase 3, open‐label, repeat‐dose safety study of diazepam nasal spray for acute treatment of seizure clusters assessed the use of a second dose up to 24 hours after the initial dose and effectiveness in potentially reducing the number of seizures.

Methods

Seizures and doses were recorded in diaries.

Results

Of 175 patients enrolled, 163 received ≥1 dose of diazepam nasal spray and were included in the safety population; those patients received a total of 4390 doses for a total of 3853 seizure clusters. Less than half of these patients used a second dose a least once during the study (79 patients [48.5%]), with a total of 485 second doses for seizure clusters (12.6% of all seizure clusters). Among these 79 patients, 33 (41.8%) used only one second dose during the study (range: 1–82). The proportion of seizure clusters treated with a second dose over time was consistently low across 24 h: 0–4 h, 152 (3.9%); 4–6 h, 72 (1.9%); 6–8 h, 39 (1.0%); 8–12 h, 55 (1.4%); 12–16 h, 42 (1.1%); 16–20 h, 42 (1.1%); 20–24 h, 83 (2.2%). Rates of treatment‐emergent adverse events (TEAEs) and treatment‐related TEAEs occurring within 1 day of a second dose were low (15.2% and 5.1%, respectively).

Significance

Patients with epilepsy may experience seizure clusters lasting up to 24 hours, and little is known about the effectiveness of rescue therapies for that duration. The current labeling of the US Food and Drug Administration (FDA)–approved outpatient treatments for seizure clusters (rectal diazepam, intranasal midazolam, and diazepam nasal spray) allows for a second dose, if needed, for control. These findings support the safety profile of second doses, and the low use supports the effectiveness of diazepam nasal spray across 24 hours.

Implications of Seizure-Cluster Treatment on Healthcare Utilization: Use of Approved Rescue Medications

PURPOSE

People with epilepsy may experience seizure clusters despite a stable regimen of antiseizure medications. Such clusters have the potential to last ≥24 hours, typically occur in the community setting, and may progress to medical emergencies, such as status epilepticus, if untreated. Thus, long-acting rescue therapy for seizure clusters is needed that can be administered by nonmedical individuals outside a hospital. Benzodiazepines are the foundation of rescue therapy for seizure clusters. The approved outpatient treatments (ie, diazepam, midazolam) have differing profiles that may affect multiple aspects of health-care utilization. The current labeling of these medications allows for a second dose if needed to control the cluster. Although no head-to-head studies directly comparing rescue treatments have been conducted, differences between studies with generally similar designs may provide context for the potential importance of second doses of rescue therapy on health-care utilization.

METHODS

For this analysis, large, long-term, open-label studies of approved seizure-cluster treatments designed for use by nonmedical caregivers were reviewed, and the percentage of seizure clusters for which a second dose was used or that were not controlled at 6, 12, and 24 hours was examined. Available data on hospitalizations were also collected.

RESULTS

The 3 identified studies meeting the inclusion criteria were for use of diazepam rectal gel, intranasal midazolam, and diazepam nasal spray. Across these studies, the use of a second dose ranged from <40% at 6 hours to <13% at 24 hours. Hospitalizations and serious treatment-emergent adverse events were reported variably across these studies.

CONCLUSION

These results demonstrate the importance of second doses of rescue therapy for seizure clusters for optimizing health-care utilization. Need for second doses should be included as one component. In turn, when second doses are needed, they have the potential to curtail emergency department use and hospitalization and to prevent further seizure clusters.