Abstracts

Rationale: Perampanel is a once-daily oral anti-seizure drug (ASD) for partial-onset seizures (POS) and primary generalized tonic-clonic seizures. There is limited information on real-world use of perampanel as an ASD in adolescent patients in the US. PROVE (Study 506; NCT03208660) is a retrospective, multicenter, non-interventional Phase IV study assessing retention rate, safety, and dosing experience of perampanel administered to patients with epilepsy during routine clinical care. Here, we report results from a subgroup analysis of adolescent patients (aged 12 to <18 years). Methods: Data were obtained from medical records of patients who initiated perampanel treatment after January 1, 2014. Follow-up was completed on March 15, 2019. Based on the Safety Analysis Set (SAS), the primary endpoint was retention rate (proportion of patients remaining on perampanel at 3, 6, 12, 18, and 24 months following treatment initiation). Safety, efficacy, and dosing experience were secondary objectives. Results: The SAS consisted of 1693 patients, of whom 292 were aged 12 to <18 years (mean [standard deviation (SD)] age: 14.7 [1.7] years; 50.0% female; mean [SD] age at epilepsy diagnosis: 6.4 [5.0] years; mean [SD] time since epilepsy diagnosis: 8.9 [5.0] years). Seizure types included: generalized tonic-clonic, n=148 (50.9%); complex partial, n=147 (50.5%); POS with secondary generalization, n=95 (32.6%). Perampanel dose was titrated as follows: weekly (17.5% of patients), every 2 weeks (19.5%), every 3 weeks (1.4%), 'other' (47.9%), and 'unknown' (13.7%). The mean (SD, range) maximum perampanel dose was 6.7 (3.1, 2-20) mg/day and the mean (SD, range) cumulative duration of exposure to perampanel was 17.1 (15.6, 0.0-75.5) months. Most patients (70.5%) were receiving 1-3 concomitant ASDs at Baseline. At the end of the study, 154 (52.7%) adolescent patients were ongoing on perampanel and 132 (45.2%) had discontinued. Primary reasons for discontinuing included adverse events (n=50 [17.1%]) and inadequate therapeutic effect (n=41 [14.0%]). Retention rates are shown in Figure 1 for those patients who remained on perampanel for 3, 6, 12, 18, and 24 months; at 24 months following treatment initiation, 88/167 (52.7%) patients remained on perampanel. TEAEs were reported in 110 (37.7%) patients; aggression (6.2%), somnolence (5.8%), and dizziness (4.8%) were the most common. Conclusions: These results from PROVE suggest that daily oral doses of adjunctive perampanel are generally well tolerated, with favorable retention rates for up to 2 years in adolescent patients aged 12 to <18 years with epilepsy. Funding: Eisai Inc.