Viloxazine Extended-Release Capsules in Children and Adolescents with ADHD: Final Results of a Long-Term, Phase 3, Open-Label Extension Study

Introduction Viloxazine ER (extended-release capsules; Qelbree ® ) is a nonstimulant medication, FDA-approved for ADHD in children (≥6 years) and adults. Efficacy and safety for children and adolescents were evaluated in one phase 2 [NCT02633527]and four phase 3 [NCT03247517, NCT03247556, NCT03247530, and NCT03247543], double-blind (DB), placebo-controlled trials that fed into a long-term, open-label extension (OLE) trial [NCT02736656]. Here we report the findings from this OLE trial. Methods Participants completing the DB trials were eligible for the OLE. Viloxazine ER was initiated at 100 mg/day (children) or 200 mg/day (adolescents) and adjusted (if needed) over a 12-week Dose-Optimization Period (up to 400 mg/day [children] or 600 mg/day [adolescents]). Maintenance treatment then continued up to 72 months. Safety assessments included adverse events (AEs), clinical laboratory tests, vital signs, ECG (12-lead), and the Columbia Suicide Severity Rating Scale (C-SSRS). Efficacy assessments included the ADHD Rating Scale, 4 th (Phase 2) or 5 th (Phase 3) Edition (ADHD-RS-IV/5), and the Clinical Global Impression-Improvement (CGI-I) scale. Efficacy was assessed relative to DB baseline at study visits ˜ 3 months apart. Two response measures, 50% improvement in ADHD-RS-IV/5 Total score and CGI-I score of 1-2, were also evaluated. Results 1100 individuals (646 children; 454 adolescents; 66.5% male/33.5% female) received treatment. Median (range) exposure to viloxazine ER was 260 (1 to 1896) days. AEs were reported by 57.3% participants, most commonly (≥5%) nasopharyngitis (9.7%), somnolence (9.5%), headache (8.9%) decreased appetite (6.0%), and fatigue (5.7%). AEs were mostly mild or moderate in severity (3.9% reported any severe AE); AEs led to viloxazine ER discontinuation for 8.2%. The mean (SD) changes from DB baseline in ADHD-RS IV/5 Total score were -17.0 (14.18) (viloxazine ER) and -11.2 (13.19) (placebo) at the last DB study visit, 24.3 (11.96) at OLE Month 3, and 22.4 (13.62) at participants’ last OLE study visit. ADHD-RS-IV/5 and CGI-I responder rates each exceeded 65% at all OLE visits following Dose-Optimization. Conclusions The safety and efficacy of viloxazine ER were maintained with long-term use in children and adolescents with ADHD. No new safety concerns emerged, and efficacy results suggested potential for continued improvement over that seen during DB treatment. Funding Supernus Pharmaceuticals, Inc.