An Open-Label Safety Study of USL261 in the Outpatient Treatment of Subjects with Seizure Clusters

To evaluate the long-term safety and tolerability of USL-261 in the treatment of seizure clusters using the following: � Occurrence of respiratory depression after study drug administration (defined as < 8 breaths per minute and/or a sustained decrease in respiratory effort requiring emergency rescue treatment with assisted breathing or intubation). � AEs � Clinical laboratory measurements. � OAA/S Sum Score and Composite Scores at the end of the seizure cluster (within 6 hours after study drug administration). � Physical, nasal, and neurological examinations. � Vital sign measurements. � C-SSRS � Requirement for ER or EMS visits.