Upsher-Smith announced the results of a year-long, open-label extension study of the safety and efficacy of Qudexy XR (topiramate) extended-release capsules as adjunctive therapy in patients with refractory partial-onset seizures (POS). The findings were presented at the 68th Annual Meeting of the American Epilepsy Society in Seattle, WA.

Patients who had completed the original 11-week double-blind treatment from the Phase 3 PREVAIL trial were eligible to enroll in the PREVAIL OLE study. Participants underwent a 3-week, blinded-conversion phase in which patients previously randomized in PREVAIL to placebo were titrated to 200mg/day of Qudexy XR; those randomized to 200mg/day were given matching placebo. Following completion of 11 weeks of treatment, changes to Qudexy XR were allowed in 50mg/week increments to a maximum of 400mg/day and to concomitant antiepileptic drugs (AEDs).

RELATED: Upsher-Smith Launches Generic Qudexy XR

Efficacy assessments were median percent reduction from baseline in weekly POS frequency and responder rates (proportion of patients with ≥50%, ≥75%, or 100% reduction in weekly POS frequency). In the 148 patients who completed the 52-week PREVAIL OLE study, a median POS reduction frequency of 51% was observed in the first three weeks; efficacy was maintained throughout the study, with a median percent reduction in POS frequency of 59% over the 52 weeks.

Qudexy XR is indicated as initial monotherapy and adjunct in partial onset or primary generalized tonic-clonic seizures and as an adjunct in Lennox-Gastaut Syndrome.

For more information visit