SPN-817 open-label extension for adults with focal-onset seizures

An Open-Label Extension, One-Year, Safety, and Efficacy Study of SPN-817 in Adults With Focal Onset Seizures

Phase 2 Interventional Supernus Pharmaceuticals, Inc. · NCT07141329

This open-label extension will try longer-term SPN-817 treatment in adults with focal-onset seizures who completed an earlier SPN-817 trial to see if it is safe and helps control seizures.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment100 (estimated)
Ages18 Years and up
SexAll
SponsorSupernus Pharmaceuticals, Inc. Industry-sponsored
Locations1 site (Port Charlotte, Florida)
Trial IDNCT07141329 on ClinicalTrials.gov

What this trial studies

This Phase 2b, multicenter open-label extension enrolls adults who completed a preceding double-blind SPN-817 study and follows them for about one year of treatment. Participants enter an 8–10 week dose titration/bridging period to reach their maximum tolerated dose, then continue in a 42–44 week open-label treatment phase before a short taper. The study collects safety, tolerability, and efficacy data during treatment and at an end-of-taper contact. Eligible participants must have been on a stable regimen of one to four antiseizure medications during the antecedent study.

Who should consider this trial

Good fit: Adults with focal-onset seizures who completed the prior double-blind SPN-817 study and are on a stable regimen of one to four antiseizure medications are ideal candidates.

Not a fit: People who have nonepileptic events that might be mistaken for seizures, those with recent severe suicidal ideation or certain suicide history, or those who did not complete the antecedent SPN-817 trial are unlikely to be eligible or benefit from this extension.

Why it matters

Potential benefit: If successful, SPN-817 could provide a tolerable longer-term treatment option that reduces seizure frequency for some adults with focal-onset seizures.

How similar studies have performed: A prior double-blind SPN-817 trial was completed, and open-label extensions like this are commonly used to collect longer-term safety and tolerability data for antiseizure medications.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

1. Completed antecedent SPN-817 double-blind study
2. Taking a stable dosage regimen (maintained during the antecedent study) of at least one antiseizure medication (ASM) and no more than 4 ASMs

Exclusion Criteria:

1. Has current nonepileptic events that could be confused by the participant and/or study staff as epileptic seizures
2. Has any suicidal behavior or suicidal ideation related to Item 4 (active suicidal ideation with some intent to act without specific plan) or Item 5 (active suicidal ideation with specific plan and intent) based on the Columbia-Suicide Severity Rating Scale (C-SSRS) assessments in the antecedent study and at Visit 1 or more than one lifetime suicide attempt.

Where this trial is running

Port Charlotte, Florida

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Focal Onset Seizuresfocal seizuresfocal epilepsyopen-label extensionanti-seizure medication
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.