Impact of Viloxazine Extended-Release Capsules (Qelbree®) on Executive Function in Adults With ADHD During an Open-Label Extension Study
Authors: Nasser Azmi , Hull Joseph , Yarullina Ilmiya , Qin Peibing , Rubin Jonathan 
Published: April 2023

Introduction

Executive function deficits (EFDs) are associated with attention-deficit/hyperactivity disorder (ADHD). Viloxazine ER (viloxazine extended-release capsules; Qelbree®) is a novel, nonstimulant, FDA-approved treatment for ADHD in persons ≥6 years of age. In a Phase 3, double-blind (DB), placebo-controlled trial in adults (NCT04016779), viloxazine ER-treated subjects exhibited significant improvement in both ADHD core symptoms (inattention and hyperactivity/impulsivity) compared to placebo. In addition, improvement in EFDs was observed in subjects using the Behavior Rating Inventory of Executive Function – Adult Version (BRIEF-A, Self-report), a 75-item scale that assesses aspects of executive function (Metacognition Index [MI]) and problems with self-regulation (Behavioral Regulation Index [BRI]) and overall functioning (Global Executive Composite [GEC]). At Week 6 in DB trial, a statistically significant greater reduction (improvement) was observed in viloxazine ER-treated subjects compared to placebo in the GEC and MI, but not in the BRI. Here, preliminary results of further BRIEF-A assessments in adults during an ongoing open-label extension (OLE) safety trial (NCT04143217) are presented.

Methods

Subjects complete the BRIEF-A at baseline and at Week 6 in the DB trial, and at Week 4 and every 8 weeks thereafter in the OLE trial. Subjects rate each BRIEF-A item on a 3-point scale (1=Never, 2=Sometimes, or 3=Often) based on the last month. Raw scores for GEC, MI, and BRI (sum of 70, 40, and 30 items, respectively) were converted to a T-score (mean=50, standard deviation=10; T-score ≥ 65 considered abnormally elevated) and then to a change from (DB) baseline (CFB) T-score. The mean [±SE] CFB T-score was calculated for the GEC, MI, and BRI by study OLE visit, and the mean last on-study OLE visit was analyzed using a paired t-test.

Results

In the OLE trial, 157 subjects received viloxazine ER (first subject dosed, 24 Jan 2020; data cut, 30 MAR 2021). The mean [±SE (n)] T-score at DB baseline between placebo and viloxazine ER groups was similar for GEC [70.9 ± 0.82 (177) and 71.0 ± 0.77 (173)], MI [73.6 ± 0.86 (178) and 74.0 ± 0.83 (173)], and BRI [63.9 ± 0.85 (177) and 63.6 ± 0.77 (174)]. The CFB T-score decreased across OLE visits in all three measures. At last on-study OLE visit, the mean [±SE (n)] CFB T-score was significantly improved for the GEC [-12.4 ± 1.23 (121); P<0.0001], the MI (-12.6 ± 1.30 (121); P<0.0001], and the BRI [-10.0 ± 1.04 (122); P<0.0001]; median viloxazine ER dose was 400 mg/day.

Conclusions

Following the DB trial, improvement in executive function continued during viloxazine ER treatment in adults throughout the OLE trial, including a significant improvement at subjects’ last on-study visit for overall functioning (GEC) and both indices (MI and BRI). Overall, the results suggest adults with ADHD may show improvement in executive function with viloxazine ER treatment.

Funding

Supernus Pharmaceuticals, Inc.