Extended-release guanfacine hydrochloride in 6-17-year olds with ADHD: a randomised-withdrawal maintenance of efficacy study.

Abstract

BACKGROUND:

Extended-release guanfacine hydrochloride (GXR), a selective α2A-adrenergic agonist, is a nonstimulant medication for attention-deficit/hyperactivity disorder (ADHD). This phase 3, double-blind, placebo-controlled, randomised-withdrawal study evaluated the long-term maintenance of GXR efficacy in children/adolescents with ADHD.

METHODS:

Children/adolescents (6-17 years) with ADHD received open-label GXR (1-7 mg/day). After 13 weeks, responders were randomised to GXR or placebo in the 26-week, double-blind, randomised-withdrawal phase (RWP). The primary endpoint was the percentage of treatment failure (≥50% increase in ADHD Rating Scale version IV total score and ≥2-point increase in Clinical Global Impression-Severity compared with RWP baseline, at two consecutive visits). The key secondary endpoint was time to treatment failure (TTF).

TRIAL REGISTRATION:

ClinicalTrials.gov identifier NCT01081145; EudraCT 2009-018161-12.

RESULTS:

A total of 528 participants enrolled; 316 (59.8%) entered the RWP. Treatment failure occurred in 49.3% of the GXR and 64.9% of the placebo group (p = 0.006). TTF was significantly longer in GXR versus placebo (p = 0.003). GXR was well tolerated.

CONCLUSIONS:

Guanfacine hydrochloride demonstrated long-term maintenance of efficacy compared with placebo in children/adolescents with ADHD. Implications of the placebo substitution design and findings with different ADHD medications are discussed.

• Authors: Jeffrey H Newcorn, Valerie Harpin, Michael Huss, Andrew Lyne, Vanja Sikirica, Mats Johnson, Josep Antoni Ramos-Quiroga, Judy van Stralen, Benoit Dutray, Sasha Sreckovic, Ralph Bloomfield, Brigitte Robertson
• Journal: Journal of child psychology and psychiatry, and allied disciplines (J Child Psychol Psychiatry) Vol. 57 Issue 6 Pg. 717-28 (06 2016) ISSN: 1469-7610 [Electronic] England
• PMID: 26871297 (Publication Type: Clinical Trial, Phase III, Journal Article, Randomized Controlled Trial)
• Copyright: © 2016 The Authors. Journal of Child Psychology and Psychiatry published by John Wiley & Sons Ltd on behalf of Association for Child and Adolescent Mental Health.

Chemical References

• Adrenergic alpha-2 Receptor Agonists
• Delayed-Action Preparations
• Guanfacine

Topics

• Adolescent
• Adrenergic alpha-2 Receptor Agonists (administration & dosage, pharmacology)
• Attention Deficit Disorder with Hyperactivity (drug therapy)
• Child
• Delayed-Action Preparations
• Double-Blind Method
• Female
• Guanfacine (administration & dosage, pharmacology)
• Humans
• Male
• Outcome Assessment, Health Care
• Treatment Failure