Safety and tolerability associated with chronic intermittent use of diazepam buccal film in adult, adolescent, and pediatric patients with epilepsy

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.

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.

Overview about Oral Films in Mental Disorders

Mental disorders are increasing worldwide, and efforts have been developed by multidisciplinary research groups to combine knowledge from different areas such as psychology, neuroscience, medicine, and biotechnology to develop strategies and products to promote the prevention of mental disorders. Excessive antipsychotic consumption is a public health problem, and innovative strategies must be devised. The development of innovative and, if possible, natural products is one of the strategies to combat this public health problem. Oral films are recent delivery systems that have been developed with several advantages that should be applied in this area. This review intends to draw attention to these new dosage forms of drugs and bioactive molecules pertinent to the field of mental health prevention and therapy and to the need for regulatory guidelines to ensure their quality and safety. This is a critical overview about strengths, weaknesses, opportunities, and threats related to oral film implementation in mental disorder treatment.

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.

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.

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.

Managing Acute Seizures: New Rescue Delivery Option and Resources to Assist School Nurses

Approximately 470,000 children and adolescents in the United States have epilepsy, 30% of whom experience seizures despite antiseizure drug regimens. School nurses, teachers, caregivers, and parents play integral roles in implementing a care plan that avoids triggers, recognizes signs, and provides supportive care—ideally, guided by a patient-specific seizure action plan, which may include the use of rescue medication. Benzodiazepines are the mainstay of seizure rescue medication; for decades, rectally administered diazepam was the only approved rescue medication for seizure clusters outside the hospital setting. However, rectal administration has limitations that could delay treatment (e.g., social acceptability, removal of clothing, positioning). More recently, intranasal midazolam (for patients ≥12 years) and intranasal diazepam (for patients ≥6 years) were approved for this indication. Training and education regarding newer forms of rescue medication should improve confidence in the ability to treat seizures in school with the goal of increasing the safety of students with epilepsy.

Overcoming the challenges of developing an intranasal diazepam rescue therapy for the treatment of seizure clusters

Seizure clusters must be treated quickly and effectively to prevent progression to prolonged seizures and status epilepticus. Rescue therapy for seizure clusters has focused on the use of benzodiazepines. Although intravenous benzodiazepine administration is the primary route in hospitals and emergency departments, seizure clusters typically occur in out‐of‐hospital settings, where a more portable product that can be easily administered by nonmedical caregivers is needed. Thus, other methods of administration have been examined, including rectal, intranasal, intramuscular, and buccal routes. Following US Food and Drug Administration (FDA) approval in 1997, rectal diazepam became the mainstay of out‐of‐hospital treatment for seizure clusters in the United States. However, social acceptability and consistent bioavailability present limitations. Intranasal formulations have potential advantages for rescue therapies, including ease of administration and faster onset of action. A midazolam nasal spray was approved by the FDA in 2019 for patients aged 12 years or older. In early 2020, the FDA approved a diazepam nasal spray for patients aged 6 years or older, which has a different formulation than the midazolam nasal product and enhances aspects of bioavailability. Benzodiazepines, including diazepam, present significant challenges in developing a suitable intranasal formulation. Diazepam nasal spray contains dodecyl maltoside (DDM) as an absorption enhancer and vitamin E to increase solubility in an easy‐to‐use portable device. In a Phase 1 study, absolute bioavailability of the diazepam nasal spray was 97% compared with intravenous diazepam. Subsequently, the nasal spray demonstrated less variability in bioavailability than rectal gel (percentage of geometric coefficient of variation of area under the curve = 42%–66% for diazepam nasal spray compared with 87%–172% for rectal gel). The diazepam nasal spray safety profile is consistent with that expected for rectal diazepam, with low rates of nasal discomfort (≤6%). To further improve the efficacy of rescue therapy, investigation of novel intranasal benzodiazepine formulations is underway.

The unmet need for rapid epileptic seizure termination (REST)

Approximately 40% of epilepsy patients will continue to experience breakthrough seizures despite stable antiepileptic drug regimens. Rescue treatments have demonstrated efficacy and safety for select seizure emergencies. Outpatient administered intranasal and rectally delivered medications are regulatory approved for acute repetitive seizures (ARS), and injectable benzodiazepines are indicated for parenteral treatment of established status epilepticus. Despite these advances, no studies have been shown to abort an ongoing seizure following patient or caregiver home administration of therapy at the first clinical sign of seizure onset. Such treatment would require rapid systemic absorption without intravenous access, and evidence of seizure cessation within minutes of administration that is superior to placebo (eg, seizure self-regulation). Rapid epileptic seizure termination (REST) treatment may apply to multiple seizure emergencies beyond ARS, including focal or generalized seizures preceded by an aura, flurries of absence or myoclonic seizures, or prolonged focal and generalized seizures at high risk of progression to status epilepticus. Novel investigational drug delivery systems have demonstrated feasibility of intraictal delivery and seizure cessation by two minutes. Ongoing randomized trials of REST treatment for diverse seizure emergencies hold the potential to decrease bouts of mental and physical incapacitation in patients with drug-resistant epilepsy.

Safety and tolerability associated with chronic intermittent use of diazepam buccal film in adult, adolescent, and pediatric patients with epilepsy

Objective

Diazepam buccal film (DBF) is in development for treatment of patients experiencing bouts of increased seizure activity. We assessed safety, tolerability, and usability of self‐ or caregiver‐administered DBF in the outpatient setting.

Methods

Patients aged 2‐65 years needing treatment with a rescue benzodiazepine at least once monthly were eligible for the study. DBF (5‐17.5 mg) was dispensed based on age and body weight. Patients/caregivers administered DBF for up to five seizure episodes per month. Adverse events (AEs) and usability assessments were recorded after the first dose, then every 3 months.

Results

Onehundred eighteen patients who used ≥1 DBF dose (adults, n = 82; adolescents, n = 19; children, n = 17) were enrolled. Eleven treatment‐related AEs (10 being mild or moderate in severity) occurred in nine (7.6%) patients over a mean of 243 days of follow‐up. No patient discontinued participation because of AEs. Mild local buccal discomfort, buccal swelling, and cheek skin sensitivity were reported by one patient each. Twenty‐two serious AEs were reported; one was treatment‐related. The three deaths reported, all unrelated to DBF, resulted from seizures or seizure with brain malignancy. Self‐administration by adults was attempted on 23.6% (188/795) of use occasions. Administration of DBF occurred under ictal or peri‐ictal conditions on 49.5% (538/1087) of use occasions, and DBF was successfully administered on a first or second attempt on 96.6% (1050/1087) of use occasions. Overall, patients received their dose of DBF on 99.2% (1078/1087) of use occasions. A second DBF dose was required within 24 hours after the first dose on 8.5% (92/1087) of use occasions.

Significance

In this observational study of chronic intermittent use, DBF was easy to administer, safe, and well tolerated in adult, adolescent, and pediatric patients with epilepsy experiencing seizure emergencies. DBF can be readily self‐administered by adults with epilepsy, as well as successfully administered by a caregiver in seizure emergencies.