Lundbeck’s Bexicaserin: Promising Epilepsy Therapy Showing Strong Seizure Reduction

Lundbeck is advancing bexicaserin - an oral 5‑HT₂C receptor agonist initially developed by Longboard Pharmaceuticals - for the treatment of severe developmental and epileptic encephalopathies (DEEs), including Dravet syndrome and Lennox–Gastaut syndrome. Lundbeck acquired the asset through a ~$2.6 billion takeover of Longboard in late 2024.

In a 12‑month open‑label extension (OLE) of the Phase 1b/2a PACIFIC trial, bexicaserin delivered a sustained and clinically meaningful reduction in motor seizures—median decrease of 59.3% from baseline. Participants who had been on bexicaserin from the trial start achieved a 60.4% reduction; those switching from placebo saw a 58.2% decrease. The safety profile remained favourable, with most participants completing the year-long study and common adverse events including respiratory infections, decreased appetite, lethargy and others.

Bexicaserin is currently moving through a global Phase III program called “DEEp,” which includes the DEEp SEA trial in Dravet syndrome and additional studies exploring other DEEs. Lundbeck targets a potential launch in late 2028, and forecasts global peak sales of $1.5 billion to $2 billion.