Long-term safety and efficacy of clobazam for Lennox-Gastaut syndrome: Interim results of an open-label extension study

► Sustained substantial seizure improvements were seen for patients treated ≥ 2 years.► 80% retention rate indicates treatment satisfaction and therapy compliance.► There were no new safety concerns vs. results of short-term controlled trials.► Mean modal clobazam dosages did not increase with time.► A trend toward decreases in numbers of concomitant treatments was observed.