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

Neurol Ther. 2024 Feb;13(1):221-231. doi: 10.1007/s40120-023-00568-4. Epub 2024 Jan 4.

Abstract

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 ).

Keywords: Benzodiazepine; Diazepam; Early Intervention; Epilepsy; Intranasal; Rescue Therapy; Seizure Cluster; Timing; Urgency.

Plain language summary

Some people with epilepsy who take daily antiseizure drugs might still have seizures. Some of these seizures may be emergencies that can be treated with rescue medicine. For status epilepticus, rescue treatment should be given as soon as this seizure emergency is recognized. Seizure clusters are rare and might also become emergencies, but until now it had not been clear if earlier treatment would be better. Diazepam nasal spray is a rescue medicine approved to treat seizure clusters. The report used data from a study of the safety of diazepam nasal spray in people needing treatment ≥ 6 times a year. We looked at the time the seizure in a seizure cluster started to the time rescue treatment was given. We also looked at the time from taking rescue treatment to the time when that specific seizure stopped. For some seizure clusters, rescue medicine was given in < 5 min after the seizure started; on average, these seizures stopped within 2 min after rescue treatment. The total time from the start of the seizure in the seizure cluster to when it stopped was 4 min. In contrast, for seizure clusters treated after 5 min, the seizures stopped in an average of 10 min after treatment. Overall, these seizures lasted 23 min. In conclusion, this analysis found that seizures in a seizure cluster ended more quickly when diazepam nasal spray was given sooner. These findings are suggestive that select patients and caregivers should not wait to treat a seizure cluster once it has been identified.

Associated data

  • ClinicalTrials.gov/NCT02721069