Systematic review of atomoxetine data in childhood and adolescent attention-deficit hyperactivity disorder 2009-2011: Focus on clinical efficacy and safety

Background: Clinicians obtain critical prescribing knowledge from clinical papers and review articles. This is the first published systematic review of clinical atomoxetine data covering 2009-2011. Objective: We aim to update clinicians on current clinical atomoxetine data with specific reference to time of onset of efficacy and maximal efficacy. These data may allow critical analysis of comparative efficacy between atomoxetine and stimulant medications. Methods: A formal systematic review of atomoxetine data from January 2009-June 2011 was conducted. The search term used was "atomoxetine" in the English language. The search yielded 747 citations from which 106 are clinical data. This paper includes clinical efficacy and safety data and excludes quality-of-life and review papers. Results: Atomoxetine has an onset of action within 4 weeks (possibly within 1 week in subsequent responders) but requires at least 12 weeks for full response to be demonstrated. Treatment-naive cohorts (6-12 weeks) report effect sizes of 0.6-1.3. Using minimum 6-week clinical trial criteria, atomoxetine may demonstrate similar efficacy to methylphenidate comparing reduction in core ADHD symptoms in meta-analysis, although the diversity of the data makes interpretation complex. From epidemiological databases, cardiovascular and suicide-related events were similar to those seen in patients taking methylphenidate. Conclusions: Incremental response time to atomoxetine should be considered in the design of future comparative efficacy trials.