Efficacy of atomoxetine in adults with attention deficit hyperactivity disorder: An integrated analysis of the complete database of multicenter placebo-controlled trials

Persistence of attention deficit hyperactivity disorder (ADHD) into adulthood can be disabling or lead to substantial impairment. Several clinical trials of atomoxetine (ATX) in adults with ADHD have been reported following the National Institute for Health and Clinical Excellence (NICE) guidelines issued in 2008. We performed an integrated analysis of all Eli Lilly-sponsored, randomized, double-blind, placebo-controlled studies of ATX in adults with ADHD completed as of May 2012. Individual patient data were pooled from six short-term (10-16 week) studies (1961 patients) and three longer-term (six-month) studies (1413 patients). In the short-term analysis, ATX patients achieved a significantly greater mean reduction in ADHD symptoms than placebo patients (-12.2 vs -8.1; Conners' Adult ADHD Rating Scale-Investigator-Rated: Screening Version (CAARS-Inv: SV); p<0.001). In the longer-term analysis, respective improvements after six months were -13.2 vs -9.7 (p<0.001). Response rates at study endpoints for ATX vs placebo, based on CAARS-Inv: SV improvement ≥ 30% and Clinical Global Impressions of ADHD-Severity (CGI-ADHD-S) ≤ 3 were 34.8% vs 22.3% in the short-term and 43.4% vs 28.0% after six months, and CAARS-Inv: SV improvements ≥ 40% were 41.3% vs 25.3% in the short-term and 44.0% vs 31.4% after six months (all p<0.001). Overall, ATX had a clinically significant effect in adults with ADHD, with reductions in core symptoms and clinically meaningful responder rates.