This study will evaluate the effectiveness and safety of an investigational drug, IV ganaxolone, as adjunctive therapy to standard of care to treat subjects with status epilepticus.

This is a double-blind, randomized, placebo-controlled study to evaluate the safety, tolerability, and efficacy of adjunctive IV ganaxolone in subjects with SE.

Study drug will be added to standard of care before IV anesthetic during the treatment of SE.

Subjects will be screened for inclusion/exclusion criteria prior to receiving study drug as adjunctive therapy by continuous IV. Subject's will be followed up for 3 weeks post-treatment.

Subjects who are known to be at risk for SE may be consented and/or assented prior to an SE event.

Inclusion Criteria:

• Subjects 12 years of age and older
• Clinical and/or electrographic seizures

Exclusion Criteria:

• Life expectancy of less than 24 hours
• Anoxic brain injury as primary cause of SE
• Recent (<24 hour) traumatic brain injury as the primary cause of SE
• Administered anesthesia for the treatment of SE