Diazepam Nasal Spray Terminates Most Pediatric Status Epilepticus Episodes in Seizure Clusters, Post Hoc Analysis Shows

A new post hoc analysis presented at the 55th Child Neurology Society (CNS) Annual Meeting, held October 14-17, 2026, in Montreal, Canada, showed that treatment with diazepam nasal spray (Valtoco; Neurelis) terminated most tonic-clonic status epilepticus (SE) episodes occurring in seizure clusters among patients aged 2 to 17 years, typically with a single dose. A second analysis reported that intervals between treated seizure clusters lengthened over time, and a third study revealed that only about 1 in 5 children with seizure clusters at a Canadian pediatric epilepsy center had been prescribed a rescue medication.¹

“We are pleased to join the child neurology community at this year's annual meeting to discuss the latest advances in research and clinical findings in the treatment of epilepsy and other chronic neurological conditions,” Adrian L. Rabinowicz, MD, chief medical officer at Neurelis, said in a statement.¹ “There is a wealth of study data on treatment of seizure clusters in people with epilepsy, and we believe continued analyses can help provide meaningful insights for the care of people living with the challenges associated with the disease.”

The SE analysis pooled data from a phase 1/2a study (NCT05076838) of patients aged 2 to 5 years (n = 36) and the phase 3 long-term safety study (NCT02721069), which contributed 78 patients aged 6 to 17 years. Using International League Against Epilepsy criteria for tonic-clonic SE (t1, 5 minutes; t2, 30 minutes), investigators identified 266 SE episodes.

The median time from SE onset to administration of diazepam nasal spray was 10 minutes, and the median time from administration to SE termination was 5 minutes, for a median total seizure duration of 18.5 minutes. Overall, 73.3% of SE episodes terminated before t2, 59.8% terminated within 20 minutes of administration, and 92.5% required only a single dose. SE recurred in 24 hours of initial termination in 6.4% of episodes.

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A second poster applied the SEIzure interVAL (SEIVAL) metric, defined as the time between treated seizure clusters, across 70-day periods. Among patients aged 2 to 5 years in the phase 1/2a study with at least 1 SEIVAL (n = 22), mean SEIVAL increased from 24.4 days in period 1 to 49.4 days in period 4.

In a consistent cohort with SEIVALs in each of the first 3 periods (n = 8), mean SEIVAL increased from 16.4 to 21.2 days. In the phase 3 study, mean SEIVAL among patients aged 6 to 17 years increased from 15.2 days in period 1 to 28.8 days in period 4 (n = 46). These findings were consistent with prior 90-day SEIVAL analyses, and no new safety signals were identified.

The third analysis drew on a standardized point-of-care electronic health note from the Comprehensive Children’s Epilepsy Centre at Alberta Children’s Hospital in Calgary. Of 3588 patients with seizures, 327 (9.1%) met inclusion criteria for the seizure cluster population. Genetic or metabolic causes were the most commonly reported known etiology (19.3% of 259 patients), and infantile epileptic spasms syndrome was the most common epilepsy syndrome (23.8% of 147 patients). Only 65 patients (19.9%) in the seizure cluster population had been prescribed a rescue medication.

Diazepam nasal spray, a benzodiazepine formulated with Intravail transmucosal absorption enhancement technology, was initially approved by the FDA in 2020 for the acute treatment of seizure clusters in patients aged 6 years and older. In April 2025, the FDA expanded the indication to patients aged 2 years and older based on pharmacokinetic and safety data from the phase 1/2a study, with second-dose use within 24 hours serving as a proxy for effectiveness.² The label carries a boxed warning for risks with concomitant opioid use, abuse and misuse, and dependence and withdrawal reactions; the most common adverse reactions are somnolence, headache, and nasal discomfort.³

The findings presented at CNS 2026 should be interpreted with caution. All 3 analyses were post hoc or observational, and the SE and SEIVAL data come from open-label studies without a comparator arm, so the rate of SE termination cannot be attributed to treatment alone. Increases in SEIVAL may reflect factors beyond a drug effect, including changes in caregiver behavior, the natural course of seizure clusters, or patient attrition, and the consistent cohort in the youngest group was small. In addition, the real-world findings come from a single Canadian center.

Click here for more coverage of CNS 2026.

REFERENCES
1. Neurelis to present analyses of study data from pediatric patients with seizure clusters at the Child Neurology Society Annual Meeting. News release. Neurelis. October 15, 2026. Accessed October 19, 2026. https://www.neurelis.com/neurelis-to-present-analyses-of-study-data-from-pediatric-patients-with-seizure-clusters-at-the-child-neurology-society-annual-meeting/
2. Neurelis announces FDA approval for immediate use seizure medication Valtoco (diazepam nasal spray) in ages 2 to 5. News release. Neurelis. April 2025. Accessed October 19, 2026. https://www.prnewswire.com/news-releases/neurelis-announces-fda-approval-for-immediate-use-seizure-medication-valtoco-diazepam-nasal-spray-in-ages-2-to-5-302430066.html
3. Valtoco (diazepam nasal spray). Prescribing information. Neurelis, Inc. Accessed October 19, 2026. https://www.valtoco.com/sites/default/files/pdf/Prescribing_Information.pdf