Treatment of prolonged seizure with diazepam nasal spray: An exploratory post hoc cohort analysis.

BACKGROUND

Benzodiazepines are used in first-line rescue therapy as immediate-use seizure medication for the treatment of seizure clusters and prolonged seizures. Their use varies across clinical practices and conditions, and they can be used promptly when indicated. Clinical studies have demonstrated seizure termination within 2 min when diazepam nasal spray is used to treat seizure clusters within 5 min, but the response when treating longer duration seizures in a cluster remains to be characterized.

OBJECTIVE

To describe and assess timing and dosing of diazepam nasal spray in the subset of prolonged seizures within seizure clusters in a larger dataset of all treated seizure clusters collected during a long-term safety study of diazepam nasal spray.

METHODS

Using timing data recorded in seizure diaries, this post hoc analysis and associated sensitivity analyses focused on prolonged seizures treated 5 to 15 min after the seizure start. Measures included time to treatment administration and time to seizure termination. Second-dose data were used as a proxy for effectiveness.

RESULTS

In this group of seizure clusters treated 5 to 15 min after seizure start, median time drug administration was 6 min after seizure start, median time from drug administration to seizure termination was 7 min, and median overall seizure duration was 15 min. Sensitivity analyses by age, epilepsy type, and high seizure frequency confirmed this pattern. Use of a second dose occurred in 9.3 % of episodes, with the majority of second doses administered ≤ 4 h after the first dose. Safety results from the overall study showed 82.2 % of patients had ≥ 1 treatment-emergent adverse event (TEAE) irrespective of relationship to treatment, during a mean participation of ∼ 1.5 years. In addition, 30.7 % patients had a serious TEAE, and 18.4 % had TEAEs deemed at least possibly related to the study drug, none of which were serious. No events of cardiorespiratory depression were reported.

CONCLUSIONS

Although immediate use of diazepam nasal spray (within 5 min) resulted in quicker seizure termination, a treatment delay of 5 to 15 min still produced rapid termination of the seizure cluster with high first-dose effectiveness and an overall acceptable safety profile. These findings suggest that diazepam nasal spray maintains effectiveness in prolonged seizures within a cluster with delayed treatment.