A post hoc analysis of the effect of viloxazine extended-release capsules on learning and school problems in children and adolescents with attention-deficit/hyperactivity disorder.

Improvement in attention-deficit/hyperactivity disorder (ADHD) symptoms vs. placebo was reported in a series of pediatric clinical trials of viloxazine extended-release capsules (viloxazine ER; Qelbree™). This post hoc analysis of those studies evaluated the effect of viloxazine ER on learning and school problems (LSPs). We used data from four Phase 3 placebo-controlled trials of 100-600 mg/day viloxazine ER (N = 1354; 6-17 years of age). LSPs were evaluated using the School domain of the Weiss Functional Impairment Rating Scale-Parent Report (WFIRS-P-S) and the Learning Problems content scale of the Conners 3rd Edition-Parent Short Form (C3PS-LP) at baseline and end of study (≥ Week 6). ADHD symptoms were assessed weekly using the ADHD Rating Scale 5th Edition. The analyses were performed using the general linear mixed model with participant as a random effect. The responder analyses were performed using the Chi-square test. Viloxazine ER demonstrated significantly greater improvements in WFIRS-P-S (p < 0.0001) and C3PS-LP (p = 0.0113) scores vs. placebo. The response rate for the WFIRS-P-S was significantly greater for viloxazine ER vs. placebo (p = 0.001), and the number needed to treat (NNT) was 10.3 (effect size 0.7). Conversely, response rates for C3PS-LP did not differ between groups (p = 0.9069). In addition to ADHD symptoms improvement demonstrated in previous studies, viloxazine ER significantly reduced LSPs in pediatric subjects with ADHD. The responder analyses and NNT estimates indicate that a substantial number of children and adolescents with ADHD treated with viloxazine ER improved in clinically assessed LSPs.

Viloxazine extended-release capsules as an emerging treatment for attention-deficit/hyperactivity disorder in children and adolescents.

INTRODUCTION: Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by inattention and/or hyperactivity and impulsivity. Viloxazine extended-release (ER) capsules (Qelbree®) is a US Food and Drug Administration-approved nonstimulant treatment option for children, adolescents, and adults with ADHD. AREAS COVERED: This review manuscript summarizes the neurobiology of ADHD and currently available treatment options before discussing viloxazine pharmacology, efficacy, safety, and tolerability data from phase II and III trials in children and adolescents (6-17 years old). Viloxazine clinical efficacy has also been further demonstrated by post hoc analyses of pediatric clinical trial results. EXPERT OPINION: Current stimulant and nonstimulant treatments for ADHD may be suboptimal given low response rates and that tolerability issues are frequently experienced. Preclinical and clinical evidence has implicated both the role of catecholamine and serotonin signaling in the pathophysiology of ADHD and the pharmacologic effect of viloxazine on these critical neurotransmitter systems. With a relatively rapid onset of action, sustained symptom improvement, and clinical benefit in ADHD-associated impairments (functional and social), viloxazine ER represents a novel and emerging ADHD treatment option.

Efficacy and Safety of SPN-812 (Extended-Release Viloxazine) in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analysis.

BACKGROUND: SPN-812 has been approved for attention-deficit/hyperactivity disorder (ADHD) treatment in children and adolescents. OBJECTIVE: We aimed to analyze the efficacy and safety of different doses of SPN-812 for ADHD pediatric patients of different ages, verify its clinical efficacy, and evaluate its safety. METHODS: Up until 30 August 2023, randomized controlled trials (RCTs) were searched in EMBASE, MEDLINE, the Cochrane Library, and clinicaltrials.gov to evaluate different doses of SPN-812 and a placebo. RESULTS: We pooled 1619 patients from five RCTs with a duration of 6-8 weeks. Patients (6-17 years old) in SPN-812 (100, 200, and 400 mg/d) groups were superior to the control group in all efficacy outcomes with lower attention-deficit/hyperactivity disorder rating scale-5 (ADHD-RS-5), Conners 3-parent short form composite T score (Conners 3-PS), Weiss functional impairment rating scale-parent (WFIRS-P), and increased clinical global impression-improvement (CGI-I) score (both p < 0.05). At the same time, only SPN-812 300 mg/d did not show a significantly high risk of the adverse events (AEs) such as somnolence and decreased appetite (p = 0.09). There was no significant difference between placebo and SPN-812 groups (100, 200, and 400 mg/d) in serious adverse events (SAEs) such as syncope. The subgroup analyses showed that, both in children and adolescents subgroups, SPN-812 showed better efficacy than the placebo. The two age subgroups showed a significantly higher risk of AEs and an insignificant risk of SAEs than the placebo. CONCLUSION: At present, SPN-812 (100, 200, and 400 mg/d) is superior to the corresponding control in efficacy measures. However, the safety problem cannot be ignored.

Viloxazine for Attention-Deficit Hyperactivity Disorder: A Systematic Review and Meta-analysis of Randomized Clinical Trials.

Background: Recently, the United States Food and Drug Administration (USFDA) approved viloxazine extended-release (ER) to manage attention-deficit hyperactivity disorder (ADHD) in pediatric patients of 6-17 years of age. Objective: To perform a meta-analysis to determine the safety and efficacy of viloxazine ER in the management of ADHD. Data Source and Methods: A literature search was performed through the databases Cochrane Library, PubMed, and clinicaltrials.gov, for a period from inception to August 2021, with the keywords: viloxazine, SPN-812, ADHD, and randomized clinical trials. The randomized controlled trials published in English language that analyzed the efficacy and safety were included. The risk of bias (RoB) was assessed by RoB tool. The outcomes included in this study were the proportion of patients with a 50% reduction in ADHD-Rating Scale-5 (ADHD-RS-5 responders) and improvement in CGI-I scale and the proportion of patients with at least one adverse event, the incidence of somnolence and Serious Adverse Events (SAEs). Results: This meta-analysis includes 1605 patients from five randomized clinical trials; all of the trials were at low risk of bias. Viloxazine group had more ADHD-RS-5 responders as compared to placebo; RR = 1.62; 95% CI = 1.36-1.93; P = <.00001. Significantly higher number of patients showed improved CGI-I score; RR = 1.53; 95% CI = 1.32-1.78; P = <.00001. A higher proportion of patients was observed with at least one adverse event (RR = 1.52; 95% CI = 1.24-1.85; P = <.0001), and somnolence (RR = 3.93; 95% CI = 2.11-7.31; P = <.0001) in viloxazine group. The incidence of SAEs was more in viloxazine group (RR = 2.98; 95% CI = .67-13.3; P = .15). Conclusions: Viloxazine was found to be significantly superior to placebo in both efficacy outcomes. Adverse events and somnolence were significantly more than the placebo. The incidence was SAEs was more in the viloxazine group but was not statistically significant.

Once-Daily SPN-812 200 and 400 mg in the treatment of ADHD in School-aged Children: A Phase III Randomized, Controlled Trial.

PURPOSE: SPN-812 (viloxazine extended-release) is under investigation for the treatment of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents. This Phase III study evaluated the efficacy and tolerability of SPN-812 200 and 400 mg once daily in children 6-11 years of age with ADHD. METHODS: Patients were randomly assigned to receive SPN-812 200 mg, SPN-812 400 mg, or placebo, once daily for 8 weeks (including ≤3 weeks titration period). The primary efficacy endpoint was the change from baseline (CFB) in ADHD Rating Scale (RS)-5 Total score at end of study (EOS). Key secondary endpoints included Clinical Global Impression-Improvement (CGI-I) score at EOS, CFB in Conners 3-Parent Short Form (PS) composite T-score at EOS, and CFB in Weiss Functional Impairment Rating Scale-Parent (WFIRS-P) Total average score at EOS. FINDINGS: A total of 313 patients were enrolled, with 301 in the intent-to-treat population (194 boys, 107 girls; mean age [SD], 8.4 [1.7] years). At EOS, the CFBs in ADHD-RS-5 Total score and CGI-I score were significantly improved with both 200- and 400-mg/d SPN-812 versus placebo (ADHD-RS-5, P = 0.0038 and 0.0063, respectively; CGI-I, P = 0.0028 and 0.0099). At EOS, the CFB in Conners 3-PS composite T-score was significantly improved with 200- (P = 0.0064), but not 400-mg/d (P = 0.0917), SPN-812 compared to placebo. No significant difference between the groups was found in WFIRS-P Total average score. The rate of discontinuations due to adverse events in both SPN-812 treatment groups combined was <5%. IMPLICATIONS: SPN-812 200 and 400 mg once daily was associated with improvements in ADHD symptoms in school-aged children and was generally well tolerated. ClinicalTrials.gov identifier: NCT03247543.

Population Pharmacokinetics of Viloxazine Extended-Release Capsules in Pediatric Subjects With Attention Deficit/Hyperactivity Disorder.

Viloxazine extended-release capsules (viloxazine ER; Qelbree) is a novel nonstimulant, recently approved by the US Food and Drug Administration for the treatment of ADHD in pediatrics. Here, we characterize the pharmacokinetics (PK) of viloxazine and its major metabolite, 5-HVLX-gluc, using a population PK model and evaluate the impact of 1-4 days of missed viloxazine ER doses on viloxazine PK. Data from 4 phase 3 trials in pediatric subjects treated with viloxazine ER were used to establish the PK model. Covariate analysis was conducted on the final base model. The impact of 1-4 days of missed doses on steady-state viloxazine PK was evaluated using Monte Carlo simulations. A 1-compartmental linear model with first-order absorption and elimination of the parent drug and first-order metabolite formation and elimination properly described the population PK of viloxazine and 5-HVLX-gluc. Body weight impacted the systemic exposure of viloxazine and 5-HVLX-gluc. Predicted PK parameters at steady state (mean ± standard deviation) in children receiving viloxazine ER were determined. Cmax was 1.60 ± 0.70 µg/mL at 100 mg, 2.83 ± 1.31 µg/mL at 200 mg, and 5.61 ± 2.48 µg/mL at 400 mg. AUC0-t was 19.29 ± 8.88 µg·h/mL at 100 mg, 34.72 ± 16.53 µg·h/mL at 200 mg, and 68.00 ± 28.51 µg·h/mL at 400 mg. PK parameters for adolescents receiving viloxazine ER were also determined. Cmax was 2.06 ± 0.90 µg/mL at 200 mg, 4.08 ± 1.67 µg/mL at 400 mg, and 6.49 ± 2.87 µg/mL at 600 mg. AUC0-t was 25.78 ± 11.55 µg·h/mL at 200 mg, 50.80 ± 19.76 µg·h/mL at 400 mg, and 79.97 ± 36.91 µg·h/mL at 600 mg. Simulations revealed that, regardless of the duration of the dosing interruption, viloxazine concentration returned to steady-state levels after approximately 2 days of once-daily dosing of viloxazine ER.

Impact of Paroxetine, a Strong CYP2D6 Inhibitor, on SPN-812 (Viloxazine Extended-Release) Pharmacokinetics in Healthy Adults.

SPN-812 (viloxazine extended-release) is a novel nonstimulant recently approved as a treatment for attention-deficit/hyperactivity disorder in children and adolescents. Given that SPN-812 is metabolized by CYP2D6 and may be coadministered with CYP2D6 inhibitors, this trial investigated the pharmacokinetics and safety of SPN-812 coadministered with the potent CYP2D6 inhibitor paroxetine. In this single-sequence, 3-treatment period study in healthy volunteers, subjects received a single oral dose of 700 mg SPN-812 alone (period 1), 20 mg daily paroxetine (10 days, period 2), followed by concurrent administration of SPN-812 and paroxetine (period 3). Blood samples were collected for 72 hours post-SPN-812 dosing and analyzed for viloxazine and its primary metabolite, 5-HVLX-gluc. Twenty-two healthy adults were enrolled; all completed the trial. The potential for drug interaction between SPN-812 and paroxetine was assessed using analysis of variance on the log-transformed pharmacokinetic parameters Cmax , AUC0-t , and AUCinf . The least-squares geometric mean ratios for viloxazine were (reported as the ratio of combination/SPN-812 alone) Cmax , 116.04%; 90%CI, 109.49%-122.99%; AUC0-t , 134.65%; 90%CI, 127.65-142.03; and AUCinf , 134.80%; 90%CI, 127.94%-142.03%. CYP2D6 inhibition resulted in a modest change (<35%) on viloxazine AUCs with no change in Cmax . All adverse events were mild in severity.

Translating Attention-Deficit/Hyperactivity Disorder Rating Scale-5 and Weiss Functional Impairment Rating Scale-Parent Effectiveness Scores into Clinical Global Impressions Clinical Significance Levels in Four Randomized Clinical Trials of SPN-812 (Viloxazine Extended-Release) in Children and Adolescents with Attention-Deficit/Hyperactivity Disorder.

Objectives: Clinical trials in psychiatry frequently report results from lengthy, comprehensive assessments to characterize a subject emotionally, cognitively, and behaviorally before and after treatment. However, the potential treatment implications of these results and how they translate into clinical practice remain unclear. Conversely, the Clinical Global Impressions (CGI) scales are quick, intuitive assessments used to assess the functional impact of a treatment in clinically relevant terms. The objectives of the present analyses are to translate scores from comprehensive assessments of symptom severity and functional impairment into clinically meaningful CGI levels. Methods: These post-hoc analyses use data integrated from four pivotal Phase 3 trials in attention-deficit/hyperactivity disorder (ADHD) in children and adolescents treated with the novel nonstimulant SPN-812 (Viloxazine Extended-Release). In this study, we evaluated the ADHD Rating Scale-5 (ADHD-RS-5) and Weiss Functional Impairment Rating Scale-Parent (WFIRS-P), assessments of symptom severity and functional impairment, respectively, by linking these scales with the CGI scales at baseline and end of study. Results: For participants that improved, a one-level change on the CGI-Improvement (CGI-I) was associated with a 10-15-point change on the ADHD-RS-5, and a 0.2-0.5-point change on the WFIRS-P. On the CGI-I, ratings of much improved and very much improved were associated with a percent score decrease (i.e., improvement) of ∼55% and 80% on the ADHD-RS-5 and ∼40% and 70% on the WFIRS-P, respectively. Differences between children and adolescents were minor and are unlikely to be clinically meaningful. Conclusion: These post-hoc analyses provide clinically meaningful benchmarks for the interpretation of scores on the ADHD-RS-5 and WFIRS-P in terms of CGI evaluations in subjects with ADHD. These results may be useful for physicians seeking to understand a treatment's potential impact on their ADHD patients or for researchers looking to define their study results within a clinically relevant context. Data are from clinical trials NCT03247530, NCT03247543, NCT03247517, and NCT03247556.

A Phase III, Randomized, Placebo-controlled Trial to Assess the Efficacy and Safety of Once-daily SPN-812 (Viloxazine Extended-release) in the Treatment of Attention-deficit/Hyperactivity Disorder in School-age Children.

PURPOSE: The limitations of current US Food and Drug Administration (FDA)-approved medications for the treatment of attention-deficit/hyperactivity disorder (ADHD) set the need for the development of novel, effective, and tolerable medications to treat this disorder. The purpose of this study was to evaluate whether treatment with SPN-812 (viloxazine extended-release) significantly reduces symptoms of ADHD in children. METHODS: This study was a randomized, double-blind, placebo-controlled 6-week trial to assess the efficacy and safety of once-daily 100- and 200-mg SPN-812 in the treatment of ADHD in male and female children 6-11 years of age. Inclusion criteria required subjects to have a confirmed Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, ADHD diagnosis, an ADHD-Rating Scale-5 (ADHD-RS-5) score ≥28, a Clinical Global Impression-Severity score ≥4, and for subjects to be free of ADHD medication ≥1 week before randomization. The primary efficacy endpoint was the change from baseline (CFB) at end of study (EOS) in ADHD-RS-5 Total score. Key secondary endpoints included Clinical Global Impression-Improvement (CGI-I) scores at EOS and CFB at EOS in the Conners 3-Parent Short Form (Conners 3-PS) Composite T-score and the Weiss Functional Impairment Rating Scale-Parent (WFIRS-P) Total average score. Safety assessments included adverse events (AEs), laboratory tests, vital signs, physical examinations, ECGs, and the Columbia-Suicide Severity Rating Scale. The primary efficacy endpoint was analyzed by using a mixed model for repeated measures; all secondary measures were analyzed by using an ANCOVA model. RESULTS: A total of 477 subjects were randomized to treatment (intent-to-treat population, n = 460). The majority of subjects were male (63%) and either White (51.3%) or African American (43.7%). The demographic and baseline characteristics between the groups were similar. Statistically significant improvements in ADHD-RS-5 Total score were observed in both the 100- and 200-mg/day SPN-812 treatment groups compared to placebo at week 1 of treatment (P = 0.0004 and P = 0.0244, respectively), which was maintained through EOS (P = 0.0004 and P < 0.0001). Significant improvements were also observed at EOS in the CGI-I scale (P = 0.0020 and P < 0.0001), Conners 3-PS Composite T-score (P = 0.0003 and P = 0.0002), and WFIRS-P Total average score (P = 0.0019 and P = 0.0002) versus placebo. Treatment-related AEs reported in ≥5% of subjects included somnolence, decreased appetite, and headache. The discontinuation rate due to AEs was <5%. IMPLICATIONS: SPN-812 significantly reduced ADHD symptoms in children and was well tolerated. SPN-812 may prove to be an effective treatment for children with ADHD. ClinicalTrials.gov identifier: NCT03247530.

New Insights into the Mechanism of Action of Viloxazine: Serotonin and Norepinephrine Modulating Properties.

BACKGROUND: Viloxazine was historically described as a norepinephrine reuptake inhibitor (NRI). Since NRIs have previously demonstrated efficacy in attention deficit/hyperactivity disorder (ADHD), viloxazine underwent contemporary investigation in the treatment of ADHD. Its clinical and safety profile, however, was found to be distinct from other ADHD medications targeting norepinephrine reuptake. Considering the complexity of neuropsychiatric disorders, understanding the mechanism of action (MoA) is an important differentiating point between viloxazine and other ADHD medications and provides pharmacology-based rationale for physicians prescribing appropriate therapy. METHODS: Viloxazine was evaluated in a series of in vitro binding and functional assays. Its effect on neurotransmitter levels in the brain was evaluated using microdialysis in freely moving rats. RESULTS: We report the effects of viloxazine on serotoninergic (5-HT) system. In vitro, viloxazine demonstrated antagonistic activity at 5-HT2B and agonistic activity at 5-HT2C receptors, along with predicted high receptor occupancy at clinical doses. In vivo, viloxazine increased extracellular 5-HT levels in the prefrontal cortex (PFC), a brain area implicated in ADHD. Viloxazine also exhibited moderate inhibitory effects on the norepinephrine transporter (NET) in vitro and in vivo, and elicited moderate activity at noradrenergic and dopaminergic systems. CONCLUSION: Viloxazine's ability to increase 5-HT levels in the PFC and its agonistic and antagonistic effects on certain 5-HT receptor subtypes, which were previously shown to suppress hyperlocomotion in animals, indicate that 5-HT modulating activity of viloxazine is an important (if not the predominant) component of its MoA, complemented by moderate NET inhibition. Supported by clinical data, these findings suggest the updated psychopharmacological profile of viloxazine can be best explained by its action as a serotonin norepinephrine modulating agent (SNMA).