PERPRISE: A prospective non-interventional study of PERampanel as only adjunctive treatment in patients with PRImary or SEcondarily generalized tonic-clonic seizures: First interim analysis.

objectiveTo report the interim results of the PERPRISE study (Study 509; NCT04202159), which is evaluating perampanel as the only adjunctive anti-seizure medication (ASM) in adults with focal to bilateral tonic-clonic seizures (FBTCS) or primary generalized tonic-clonic seizures (GTCS).

methodsPERPRISE is an ongoing 12-month multicenter, prospective, observational, non-interventional study of perampanel in a real-world setting in Germany. Patients are aged ≥18 years with FBTCS or GTCS due to focal or idiopathic generalized epilepsy. Perampanel, as an adjunctive therapy to ASM monotherapy ('add-on therapy') or as a substitute for one ASM in dual therapy ('substitution therapy'), is prescribed in line with its SmPC. The Interim Analysis Set comprises the first 100 patients who received ≥1 dose of perampanel and attended or discontinued prior to the ~6-month visit. Interim endpoints include retention rate, measures of effects on seizure frequency, and treatment-emergent adverse events (TEAEs).

resultsOne hundred patients were included in the Interim Analysis Set (add-on, n = 43 [43.0%]; substitution, n = 55 [55.0%]; unknown, n = 2). The 6-month retention rate was 78.0% (add-on, 83.7%; substitution, 72.7%). For the overall population with GTCS and/or FBTCS, seizure-freedom rate at 6 months was 58.8% (add-on, 72.2%; substitution, 47.9%) and 50% responder rate at 6 months was 82.6% (add-on, 89.2%; substitution, 76.6%). Retention rates and seizure outcomes were better with perampanel as an early-line treatment than as a late-line treatment. TEAEs were reported by 48 patients (48.0%), most commonly dizziness (n = 9), fatigue (n = 7), and irritability (n = 7). Sixteen patients (16.0%) withdrew from perampanel treatment due to TEAEs. SIGNIFICANCE: The interim analysis of PERPRISE offers insight into the real-world use of perampanel in Germany, including for the first time, clinical practice data from patients with GTCS and switching ASMs within a dual therapy. Further data from PERPRISE will be of value to inform clinical decision-making in this patient cohort. PLAIN LANGUAGE SUMMARY: Patients with epilepsy often take more than one medication for seizure control. This 12month study looked at patients in Germany receiving perampanel as only add-on medication. The interim analysis shows, that at 6 months, over 70% of the 100 patients continued to use perampanel; 59% experienced no seizures during treatment with perampanel, and in 83%, seizure frequency was reduced by half. Side effects occurred in 48% of patients (most commonly dizziness, fatigue, and irritability) and caused 16% to withdraw from the study. Overall, perampanel was a suitable as only add-on medication for patients with epilepsy.