Background: SPN-812 (extended-release viloxazine) is a structurally distinct, bicyclic, Serotonin Norepinephrine Modulating Agent (SNMA) being developed as a treatment for attention-deficit/hyperactivity disorder (ADHD). Here we present results of a Phase 3, randomized, double-blind, placebo-controlled study (P301) evaluating efficacy and safety of once-daily SPN-812 dosed at 100 mg or 200 mg in children ages 6-11yrs with ADHD.
Methods: Key inclusion criteria were confirmed DSM-5 ADHD diagnosis, ADHD-Rating Scale-5 (ADHD-RS-5) score ≥28, Clinical Global Impression (CGI)-Severity score ≥4, and free of ADHD medication ≥1 week before randomization. Subjects were randomized 1:1:1 to placebo:100 mg:200 mg SPN-812. Treatment included 1 week titration and 5 weeks maintenance (intent-to-treat population: N=460; placebo=155, 100 mg=147, 200 mg=158). The primary efficacy endpoint was ADHD-RS-5 total score change from baseline (CFB) at end of study (EOS). Key secondary endpoints included CGI-Improvement (CGI-I) score at EOS among other measures. Safety and tolerability assessments included adverse events (AEs) alongside other parameters.
Results: Compared to placebo, greater improvements in ADHD-RS-5 total score were observed in the 100 mg and 200 mg SPN-812 treatment groups beginning at week 1 (p=0.0004, p=0.0244; respectively) through EOS (p=0.0004, p<0.0001; respectively). A significant improvement in CGI-I score at EOS was also observed for 100 mg and 200 mg SPN-812 compared to placebo (p=0.0020, p<0.0001; respectively). Treatment-related AEs reported in ≥5% of SPN-812 subjects were somnolence, headache, and decreased appetite.
Summary: In this study, SPN-812 100 mg and 200 mg met the primary objective with statistical significance. AE-related dropouts were ≤5%, indicating SPN-812 treatment was well tolerated.
This poster was presented at the 32nd annual Psych Congress, held Oct. 3-6, 2019, in San Diego, California.