Safety and efficacy of midazolam nasal spray for the treatment of intermittent bouts of increased seizure activity in the epilepsy monitoring unit: A double-blind, randomized, placebo-controlled trial

Objective: Midazolam nasal spray (MDZ-NS) is indicated for acute treatment of intermittent, stereotypic episodes of frequent seizure activity (ie, seizure clusters, acute repetitive seizures) that are distinct from a patient's usual seizure pattern, in patients 12 years of age and older with epilepsy. This trial evaluated safety and efficacy of MDZ-NS in patients with epilepsy who were admitted to the epilepsy monitoring unit for seizure characterization/presurgical evaluation. Methods: In this randomized, double-blind, placebo-controlled phase 3 trial (P261-301; NCT01999777), eligible patients with ≥2 seizures in the 6-hour window preceding trial medication administration for whom treatment was appropriate based on investigator's judgment were randomized (1:1) to MDZ-NS 5 mg or placebo. Efficacy outcomes were proportion of patients seizure-free for 6 hours after treatment and time to first seizure within 6 hours. Safety and tolerability outcomes included treatment-emergent adverse events (TEAEs). Results: Sixty-two patients were randomized (MDZ-NS n = 31; placebo n = 31), received trial medication, and completed the trial. A higher proportion of patients on MDZ-NS than placebo were seizure-free for 6 hours following treatment (54.8% vs 38.7%); however, the 16.1% difference was not statistically significant (P =.1972). The Kaplan-Meier curve of time to first seizure showed separation of both groups in favor of MDZ-NS from ~1.5 hours post-dose and throughout the 6-hour Treatment phase. Median time to first seizure was not estimable for MDZ-NS (>50% of patients had no seizure) and 3.9 hours for placebo (P =.1388). TEAEs with MDZ-NS were generally comparable to those with placebo. There were no deaths, serious TEAEs, or discontinuations due to TEAEs. Significance: Although the observed treatment difference may be clinically meaningful, statistical significance was not demonstrated. Results suggest that MDZ-NS 5 mg may provide improvement over placebo, with efficacy maintained for ≥6 hours post-dose. MDZ-NS was well tolerated in this population.