(347) Long-Term (52 weeks) Effects of Adjunctive Perampanel on Cognition, Growth, and Development in Japanese Pediatric Patients (Aged 4 to <12 Years) with Partial-Onset Seizures in Study 311
Pediatrician National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders
Rationale: In the U.S. and Japan, perampanel is approved for partial-onset seizures (POS; adjunctive and monotherapy) in patients aged ≥ 4 years, and adjunctive treatment of primary generalized tonic-clonic seizures (PGTCS) in patients aged ≥ 12 years. Study 311 (NCT02849626) was a multicenter, open-label, single-arm study of perampanel oral suspension in pediatric patients (aged 4 to < 12 years) with POS (with or without secondarily generalized seizures [SGS]) or PGTCS. Here, we report effects of adjunctive perampanel on cognition, behavior, growth, and development in Study 311 (Core and Extension) in Japanese patients with POS, with or without SGS. Methods: Patients completing the 27-week Core Study (4-week Pretreatment; 23-week Treatment [11-week Titration; 12-week Maintenance]) could enter Extension A (29-week Maintenance; 4-week Follow-up). Change from baseline was assessed at Week 52 for cognition (Aldenkamp-Baker Neuropsychological Assessment Schedule [ABNAS]), behavioral/emotional problems (Child Behavior Checklist [CBCL]), visuomotor skills (Lafayette Grooved Pegboard Test [LGPT]), and growth/development. High ABNAS, CBCL, and LGPT scores indicated greater problems. Cumulative data from all enrolled patients are included until their exit point. Only patients with POS were enrolled in Japan. Results: Of 65 Japanese patients with POS enrolled in the Core Study (mean [standard deviation (SD)] age: 8.2 [2.0] years; 55.4% female), 53 entered Extension A. Three Japanese patients discontinued Extension A due to patient choice, inadequate therapeutic effect, and withdrawal of consent (n=1 each). For ABNAS, mean (SD) change from baseline for total score was -4.7 (17.1) at Week 52 (n=48); ABNAS domain scores are presented in Table 1. Mean (SD) change from baseline at Week 52 for CBCL total problems was -7.2 (7.4) and -0.8 (9.8) for patients aged 1.5–5 (n=6) and 6–18 years (n=44), respectively, and, for time to complete the LGPT (dominant hand), was 4.1 (55.3) and 3.7 (25.4) seconds for patients aged ≤ 8 years (n=19) and >8 years (n=27), respectively. Perampanel had no clinically relevant impacts on growth (height/weight) or development as measured by insulin-like growth factor-1 and thyroid function. Conclusions: There were no clinically relevant changes in cognition, behavior, or growth/development parameters following long-term (52 weeks') adjunctive perampanel treatment in Japanese pediatric patients aged 4 to < 12 years with POS, with or without SGS. Funding: Please list any funding that was received in support of this abstract.: