Shire Pharmaceutical Development Ltd.

Objective: To examine efficacy and safety of adjunctive guanfacine extended release (GXR) on morning and evening ADHD symptoms using the Conners’ Global Index–Parent (CGI-P) and Before-School Functioning Questionnaire (BSFQ). Method: Participants 6 to 17 years with ADHD ( N = 461) and suboptimal psychostimulant response were maintained on current psychostimulants and randomized to dose-optimized GXR (≤4 mg/d) in the morning (GXR AM) or evening (GXR PM), or placebo. Results: CGI-P scores improved with GXR (morning assessment, GXR AM, placebo-adjusted least squares [LS] mean = -1.7, GXR PM = -2.6; evening assessment, GXR AM = -2.4, GXR PM = -3.0; all ps < .01). Parent-rated BSFQ scores reflected improved morning functioning with GXR (GXR AM, placebo-adjusted LS mean = -5.1; GXR PM = -4.7; both ps < .01). Most adverse events were mild or moderate. Conclusion: Adjunctive GXR AM or GXR PM was associated with improvements in morning and evening ADHD symptoms in children and adolescents.

In this post hoc analysis, we assessed whether guanfacine extended-release (GXR) adjunctive to a psychostimulant resulted in greater response and remission rates than placebo + psychostimulant in children and adolescents with attention-deficit/hyperactivity disorder (ADHD).

In this 9-week, double-blind, placebo-controlled dose-optimization study, participants (N = 461) aged 6 to 17 years with suboptimal response to psychostimulants were randomized to GXR on awakening (AM) + psychostimulant, GXR at bedtime (PM) + psychostimulant, or placebo + psychostimulant.

At the final on-treatment assessment, more participants in both GXR + psychostimulant groups versus the placebo + psychostimulant group achieved response as assessed by 2 criteria: reduction from baseline in ADHD Rating Scale IV (ADHD-RS-IV) total score (1) ≥40% (GXR AM + psychostimulant = 69.8%, GXR PM + psychostimulant = 70.3%, versus placebo + psychostimulant = 57.9%; p = .032 and p = .026, respectively), or (2) ≥50% (63.1%, 64.9%, versus 43.4%; p <.001 for both). Results were similar for symptomatic remission (ADHD-RS-IV total score ≤18; 61.1%, 62.2%, versus 46.1%; p = .010 and p = .005, respectively) and syndromal remission (symptomatic remission plus Clinical Global Impressions of Severity of Illness score ≤2). The most common treatment-emergent adverse events in participants receiving GXR + psychostimulant were headache (21.2%) and somnolence (13.6%).

GXR + psychostimulant treatment resulted in a greater percentage of participants meeting stringent criteria for response and remission compared with placebo + psychostimulant. The adverse event profile of adjunctive therapy was consistent with known effects of either treatment alone. Clinical trial registration information-Efficacy and Safety of SPD503 in Combination With Psychostimulants; http://clinicaltrials.gov/; NCT00734578.

The purpose of this study was to evaluate the efficacy of once-daily guanfacine extended release (GXR) monotherapy administered either in the morning or evening, using a modified Conners' Parent Rating Scale-Revised: Short Form (CPRS-R:S) assessed three times/day in children with attention-deficit/hyperactivity disorder (ADHD).

This multicenter, double-blind, placebo-controlled study randomized children 6-12 years of age with ADHD into three groups: GXR a.m. (GXR in the morning and placebo in the evening), GXR p.m. (placebo in the morning and GXR in the evening), or twice-daily placebo. The CPRS-R:S, administered in the morning, afternoon, and evening prior to each study visit, was a secondary measure of efficacy.

A total of 333 subjects were included in the analysis population (GXR a.m., n=107; GXR p.m., n=114; placebo, n=112). At visit 10, last observation carried forward (LOCF), subjects receiving GXR demonstrated significantly greater improvement from baseline in the daily mean CPRS-R:S total score, as well as in each of the morning, afternoon, and evening CPRS-R:S assessments, compared with placebo, regardless of the time of GXR administration (p<0.001 vs. placebo for GXR a.m. and GXR p.m.). In addition, subjects receiving GXR showed significantly greater improvements from baseline in each subscale score (oppositional, cognitive problems/inattention, hyperactivity, and ADHD index) compared with those receiving placebo, regardless of time of administration (p<0.003 vs. placebo across all subscales for GXR a.m. and GXR p.m.).

These results provide further support for the demonstrated efficacy of once-daily GXR in reducing ADHD symptoms, and demonstrate that response is consistent throughout the day regardless of the time of administration, with improvement seen in ratings of oppositional as well as of ADHD symptoms.