Abstracts

Rationale: Perampanel is a once-daily oral anti-seizure drug (ASD) for partial-onset seizures (POS) and primary generalized tonic-clonic seizures. In the US, perampanel is licensed in patients aged ≥4 years who have POS, with or without secondarily generalized seizures. 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 patients aged ≥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 (N=1693) included 1152 (68.0%) patients aged ≥18 years (mean [standard deviation (SD)] age: 36.5 [13.8] years; 53.8% female; mean [SD] age at epilepsy diagnosis: 18.1 [16.7] years; mean [SD] time since epilepsy diagnosis: 19.6 [14.2] years). Seizure types included: complex partial, n=732 (63.6%); generalized tonic-clonic, n=597 (51.9%); POS with secondary generalization, n=460 (40.0%). Most patients received 1–3 concomitant ASDs at Baseline (n=870 [75.5%]). Perampanel dose was titrated: weekly (19.9% of patients), every 2 weeks (18.8%), every 3 weeks (1.6%), ‘other’ (53.1%), and ‘unknown’ (6.6%). The mean (SD) perampanel dose was 5.9 (3.0) mg/day and the mean (SD, range) maximum perampanel dose was 7.0 (3.4, 1–52) mg/day. The mean (SD, range) cumulative duration of exposure to perampanel was 17.7 (16.0, 0.0–77.1) months. At the end of the study, 583 (50.6%) adult patients aged ≥18 years were ongoing on perampanel and 557 (48.4%) had discontinued; primary reasons for discontinuing included adverse event (n=238 [20.7%]) and inadequate therapeutic effect (n=133 [11.5%]). Retention rates over 24 months are shown in Figure 1; at 24 months following treatment initiation, 349/736 (47.4%) patients remained on perampanel. TEAEs were reported in 484 (42.0%) adult patients (≥18 years); dizziness (9.1%), aggression (4.9%), and irritability (4.2%) 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 adult patients aged ≥18 years with epilepsy. Funding: Eisai Inc.