Atomoxetine monotherapy compared with combination therapy for the treatment of ADHD: a retrospective chart review study

Abstract

Objective: To analyze Clinical Global Impression—Severity (CGI-S) in ADHD patients treated with atomoxetine (ATX) monotherapy versus ATX combination therapy with another ADHD-indicated medication. Methods: This was a 2-site retrospective observational chart review study of child and adult ADHD patients, not necessarily treatment naïve, but treated ≥50 days post baseline with an endpoint assessment. To adjust for measured confounders, monotherapy (n = 77) versus combination (n = 108) cohort comparisons were performed using propensity score stratification and adjusted ANCOVA. Results: There were no significant baseline cohort differences after propensity stratification. CGI-S scores after a mean 264 days of treatment were not statistically significantly different between cohorts, with no cohort differences observed in any assessed symptom subcategory. The cohorts were similar in discontinuation due to any reason, adverse event, and lack of efficacy. Conclusion: ATX combination therapy showed no evidence of additional benefit over ATX monotherapy in the treatment of ADHD in a community-based setting.

Keywords:

• ADHD
• atomoxetine
• stimulant
• polypharmacy
• combination therapy
• ADHD

Acknowledgements

The authors thank Steve Able for protocol development and general study consultation, Wenyu Ye for help with the statistical analysis plan and data output analytical review and overall statistical consultation and Shufang Wang for help with the statistical analysis plan and overall statistical consultation. Additionally, the authors thank ICON employees Sheena Kayaniyil, Suzanne Lane, Karissa Johnston and Aleksandra Gara for project management, epidemiology consultation, statistical analysis plan development, data abstraction, data management and data analysis.

Financial & competing interests disclosure

This study was funded by Lilly USA, LLC, a wholly owned subsidiary of Eli Lilly and Company that markets atomoxetine. Mason, Sarkis, Berman, Donnelly, Robb, and Holland are members of a Lilly medical advisory board that was convened to consult on the topic of combination therapy and potential study design (an activity compensated at fair market value). Clemow, Ruff, Schuh, Barnes, and Araujo are employees of Eli Lilly and Company and/or one of its wholly owned subsidiaries. The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.