A new paradigm for developing drugs in children: atomoxetine as a model

Evaluation of atomoxetine for first-line treatment of newly diagnosed, treatment-naïve children and adolescents with attention deficit/hyperactivity disorder

OBJECTIVE

To test the hypothesis that first-line treatment with atomoxetine provides superior efficacy than placebo for up to 12 weeks in improving the symptoms of Attention Deficit/Hyperactivity Disorder (ADHD).

RESEARCH DESIGN AND METHODS

This double-blind, randomized, placebo-controlled, parallel clinical trial included 151 treatment-naïve children (n = 113) and adolescents (n = 38) with newly diagnosed (< or =3 months) ADHD. Atomoxetine dose was uptitrated from 0.5 to 1.2 mg/kg/day after two weeks. Outcome assessments included the ADHD Rating Scale-IV-Parent-reported Investigator-rated (ADHDRS-IV-Parent:Inv), the Clinical Global Impression of Severity of ADHD (CGI-ADHD-S), and the incidence of adverse events. Mixed-model repeated measures analysis was used to compare scale score changes between groups.

CLINICAL TRIAL REGISTRATION

Trial registered at www.clinicaltrials.gov (study internal code: B4Z-XM-LYDM, identifier: NCT00191945).

RESULTS

Most patients were male (79.2%), of caucasian origin (96.0%) and severely ill (72.5%). Their mean age was 10.3 years. Atomoxetine-treated patients showed greater reductions from baseline to week 12 of total ADHDRS-IV-Parent:Inv score than placebo-treated patients (least square mean difference: -7.9 [95% CI: -11.0 to -4.8], corresponding to a large effect size of 0.8). Between-group mean differences increased progressively with treatment exposure from week 6 to 12 (-2.7 [-4.9 to -0.6] for total and -1.6 [-2.9 to -0.3] for inattention scores). At the end of the study, 50% of atomoxetine-treated patients (14% with placebo) showed a reduction > or =40% in total ADHDRS-IV-Parent:Inv score, and only 29% (46% with placebo) were severely ill (by CGI-ADHD-S). Treatment-related adverse events were significantly more frequent with atomoxetine (65.0%) than with placebo (37.3%), the most frequent being decreased appetite and somnolence. Only one case of decreased appetite was rated as severe. No patient discontinued treatment because of adverse events.

CONCLUSIONS

A continued improvement of symptoms is expectable until 12 weeks in treatment-naïve ADHD patients treated with atomoxetine as first-line medication. Chief limitations are the small, national sample size and the absence of data beyond the 12-week time-point.

Evaluation of patients' and parents' quality of life in a randomized placebo-controlled atomoxetine study in attention-deficit/hyperactivity disorder

OBJECTIVE

The aim of this study was to demonstrate the superior efficacy of atomoxetine with respect to placebo and to compare parent and child perceptions of health-related quality of life (HRQoL).

METHOD

This randomized, placebo-controlled, 12-week parallel clinical trial included 151 untreated children/adolescents with newly diagnosed attention-deficit/hyperactivity disorder (ADHD). Parents' and patients' reports of HRQoL were obtained separately using the Child Health and Illness Profile and compared using analysis of covariance.

RESULTS

The ADHD Rating Scale baseline mean score was 39.21. Baseline HRQoL was perceived as considerably compromised by parents, especially in the risk avoidance and achievement domains (mean t-scores, 32.47 and 33.16, respectively), but less by children, and restricted to the achievement domain (mean t-score, 41.54). Atomoxetine improved HRQoL with respect to placebo in these two domains as assessed by parents (difference between adjusted mean changes and 95% confidence interval, 8.53, 4.05-13.00 and 3.39, 0.13-6.65) and in the risk avoidance domain by patients (3.56, 1.04-6.07). A modest correlation of clinical severity with HRQoL was found in this clinical population.

CONCLUSIONS

This study confirms prior reports the impact of ADHD on the HRQoL of patients as assessed by their parents. The patients' perspective is of a lesser impact. Atomoxetine improved HRQoL as assessed by both parents and patients.

Switching from neurostimulant therapy to atomoxetine in children and adolescents with attention-deficit hyperactivity disorder : clinical approaches and review of current available evidence

This review provides practical information on and clinical reasons for switching children and young people with attention-deficit hyperactivity disorder (ADHD) from neurostimulants to atomoxetine, detailing currently available evidence, and switching options. The issue is of particular relevance following recent guidance from the National Institute for Health and Clinical Excellence and European ADHD guidelines endorsing the use of atomoxetine, along with the stimulants methylphenidate and dexamphetamine, in the management of ADHD in children and adolescents in the UK. The selective norepinephrine (noradrenaline) reuptake inhibitor, atomoxetine, is a non-stimulant drug licensed for the treatment of ADHD in children and adolescents, and in adults who have shown a response in childhood. Following the once-daily morning dose, its therapeutic effects extend through the waking hours, into late evening, and in some patients, through to early the next morning. Atomoxetine may be considered for patients who are unresponsive or incompletely responsive to stimulant treatment, have co-morbid conditions (e.g. tics, anxiety, depression), and have sleep disturbances or eating problems, for patients in whom stimulants are poorly tolerated, and for situations where there is potential for drug abuse or diversion. Atomoxetine has been shown to be effective in relapse prevention and there is suggestion that atomoxetine may have a positive effect on global functioning; specifically health-related quality of life, self-esteem, and social and family functioning. According to one study, approximately 50% of non-responders to methylphenidate will respond to atomoxetine therapy and approximately 75% of responders to methylphenidate will also respond to atomoxetine. Atomoxetine may be initiated by a schedule of dose increases and cross-tapering with methylphenidate. A slow titration schedule with divided doses minimizes the impact of adverse events within the first several weeks of treatment. Atomoxetine may be co-administered with methylphenidate during the switching period without undue concern for adverse events, such as cardiovascular effects (although monitoring of blood pressure and heart rate is necessary). Atomoxetine may be discontinued abruptly and patients may miss the occasional dose without rebound effects or discontinuation syndrome. A trial period of at least 6-8 weeks, perhaps longer, is recommended before evaluation of the overall tolerability and efficacy of atomoxetine. We conclude that patients with ADHD can be switched from neurostimulants, specifically methylphenidate, to atomoxetine, and may benefit from symptom improvement.

A multi-centre, randomised, open-label study of atomoxetine compared with standard current therapy in UK children and adolescents with attention-deficit/hyperactivity disorder (ADHD)

OBJECTIVE

To assess the broader efficacy (i.e., improvements in quality of life/functional outcomes) of atomoxetine compared with standard current therapy (SCT) in UK paediatric patients with ADHD and to explore clinician/parent/child perceptions of ADHD.

RESEARCH DESIGN AND METHODS

A total of 201 patients with ADHD were randomised into this multi-centre, open-label study to receive atomoxetine (n = 104) or SCT (n = 97) for 10 weeks. Broader efficacy was assessed using the parent-rated Child Health and Illness Profile-Child Edition (CHIP-CE) total (global) t-score. Secondary outcome measures included the five CHIP-CE domains; parent-rated Family Burden of Illness Module (FBIM); investigator-rated ADHD-Rating Scale; investigator-rated Clinical Global Impression (CGI)-Severity/Improvement scales; and child-rated Harter Self-Perception Profile (HSPP).

RESULTS

Quality of life of children/adolescents with ADHD was extremely compromised at baseline (CHIP-CE total t-scores: atomoxetine, 23.2 +/- 12.2; SCT, 23.9 +/- 11.0), and improved during the 10-week study for both groups; the CHIP-CE score was statistically significantly higher for patients treated with atomoxetine (38.4 +/- 1.3) compared with SCT (30.8 +/- 1.3) at week 10 (p < 0.001). ADHD-RS, CGI-Severity, and CGI-Improvement scores were significantly different between the groups in favour of atomoxetine (p < 0.001). There was a statistically significant difference between the groups in the HSPP Social Acceptance domain in favour of atomoxetine, but not in the five other HSPP domains or FBIM total score. Atomoxetine was well-tolerated.

CONCLUSIONS

Results from this open-label trial show that atomoxetine is superior to SCT in addressing broader efficacy and functional outcomes in UK children/adolescents with ADHD. This study contributes to the understanding of broader efficacy in children with ADHD, and is timely in light of recent NICE guidance.

Atomoxetine: a novel treatment for child and adult ADHD

Attention deficit hyperactivity disorder (ADHD) is a common chronic condition with childhood onset that can continue into adulthood. Medication is a fundamental element in the management of this disorder. Atomoxetine is the newest nonstimulant medication approved by the United States Food and Drug Administration (FDA) for the treatment of ADHD. It is the only nonstimulant medication approved by the FDA for treatment of adult ADHD. Atomoxetine is a norepinephrine reuptake inhibitor that selectively inhibits the presynaptic norepinephrine transporter. A growing body of literature supports the use of atomoxetine both in children and adults with ADHD. This paper summarizes information from the literature about atomoxetine, including pharmacokinetics, pharmacodynamics, clinical trials, dosing, and side-effects.