Quality-of-life results in adults with epilepsy using diazepam nasal spray for seizure clusters from a long-term, open-label safety study

Abstract

Background: The impact of seizure clusters and the use of intermittent rescue therapy for clusters on the quality of life (QoL) of patients with epilepsy has not been widely studied. The present analysis assessed QoL as a secondary endpoint among adult patients with seizure clusters enrolled in a long-term, phase 3, open-label safety study (NCT02721069) of diazepam nasal spray (Valtoco®). The QoL aspect of patients in this study has not been previously published.

Methods: The 12-month safety study of diazepam nasal spray enrolled patients aged 6-65 years with seizure clusters. Adults aged ≥18 years completed the Quality of Life in Epilepsy (QOLIE)-31-P at baseline (day 0) and days 30, 150, 270, and 365. This instrument includes questions about patient health and daily activities with numeric values (1-100) assigned to responses; higher scores indicate better QoL. The QOLIE-31-P includes 7 subscales: Seizure Worry, Overall QoL, Emotional Well-Being, Energy/Fatigue, Cognitive Functioning, Medication Effects, and Social Functioning; an Overall Score is calculated as a weighted composite of the 7 subscales. Comparisons were made between subgroups of patients who had frequent (≥2) and infrequent (<2) monthly dosing of diazepam nasal spray and those whose doses were administered by the patient or a care partner. This safety study was not powered to assess efficacy endpoints; descriptive statistics were calculated across time points. In addition, safety measures, including treatment-emergent adverse events, are reported.

Results: Seventy-two adults who responded to the QOLIE-31-P were included in the analyses. Mean QOLIE-31-P scores were stable or increased across time points. The mean total scores increased from day 0 to day 365 by 5.2 among patients providing data for ≥1 time point (follow-up group) and 2.2 among patients providing data at all time points (QOLIE all-assessments subgroup). Subscale means for Seizure Worry and Social Functioning showed the greatest numeric increase from baseline. Mean QOLIE-31-P scores were similar in all subgroups. The safety profile in the follow-up group was similar to that seen in all study adults.

Conclusions: Adults with refractory epilepsy who were treated with diazepam nasal spray for seizure clusters maintained or improved QOLIE subscale scores across the 12-month study period. Seizure Worry and Social Functioning subscale scores increased over time, suggesting improvement in these domains for this population with intractable epilepsy. Changes among subscale results suggest differences in sensitivity to the use of an intermittent treatment. The potential to improve patient function with treatment for seizure clusters warrants further study.

Keywords: Acute repetitive seizure; Diazepam; Intranasal; Quality of life; Rescue; Seizure cluster.