Open AccessAtomoxetine Increased Effect over Time in Adults with Attention‐Deficit/Hyperactivity Disorder Treated for up to 6 Months: Pooled Analysis of Two Double‐Blind, Placebo‐Controlled, Randomized Trials
Author(s) -
Wietecha Linda A.,
Clemow David B.,
Buchanan Andrew S.,
Young Joel L.,
Sarkis Elias H.,
Findling Robert L.
Publication year - 2016
Publication title -
cns neuroscience and therapeutics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.403
H-Index - 69
eISSN - 1755-5949
pISSN - 1755-5930
DOI - 10.1111/cns.12533
Subject(s) - atomoxetine , placebo , atomoxetine hydrochloride , randomized controlled trial , medicine , attention deficit hyperactivity disorder , rating scale , dosing , placebo controlled study , double blind , psychology , psychiatry , developmental psychology , pathology , alternative medicine , methylphenidate
Summary Introduction Changes in the magnitude of efficacy throughout 26 weeks of atomoxetine treatment, along with impact of dosing, were evaluated in adults with ADHD from two randomized, double‐blind, placebo‐controlled studies. Aims Pooled placebo (n = 485) and atomoxetine (n = 518) patients, dosed 25, 40, 60, 80 (target dose), or 100 mg daily, were assessed. Change from baseline in Conners’ Adult ADHD Rating Scale–Investigator Rated Scale: Screening Version (CAARS) total ADHD symptoms score and Adult ADHD Investigator Symptom Rating Scale (AISRS) total score were analyzed using mixed‐model repeated measures, with least squares mean change, effect size, and response rate calculated at 1, 2, 4, 8, 12, 16, 22, and 26 weeks. Results Decreases on CAARS for atomoxetine‐ versus placebo‐treated patients were consistently statistically significantly greater at every time point beginning at one week ( P ≤ 0.006, 0.28 effect size). By 4 weeks, comparison was −13.19 compared with −8.84 ( P < 0.0001, 0.45 effect size). By 26 weeks, mean change was −15.42 versus −9.71 (0.52 effect size); increase in effect size over time was most pronounced in the 80 mg group (0.82 effect size). AISRS demonstrated similar results. Atomoxetine response rate (CAARS 50% decrease) continued to increase throughout 26 weeks. Conclusions Atomoxetine treatment in adults with ADHD was associated with small effect sizes after 4 weeks and moderate effect sizes by 6 months of treatment. The data support increased effect size and response rate over time during longer‐term treatment at target dose.