The main objective of this study was to evaluate efficacy and tolerability of once-daily extended release quetiapine fumarate (quetiapine XR) monotherapy in generalized anxiety disorder (GAD). This was a 8 week randomized, 2-week follow-up, double-blind, placebo-controlled, and active-controlled study. Patients were randomized to quetiapine XR 150 (n=219) or 300 mg/day (n=207); escitalopram, 10 mg/day (n=213); or placebo (n=215). The primary endpoint was the change from randomization at week 8 in Hamilton Anxiety Rating (HAM-A) total score. Week 8 mean HAM-A total score was significantly reduced from randomization with quetiapine XR 150 mg/day (−13.9, P<0.001), 300 mg/day (−12.3, P<0.05) and escitalopram (−12.3, P<0.05) versus placebo (−10.7); significant improvements with quetiapine XR (150 and 300 mg/day) versus placebo (P<0.001) were also shown at day 4. At week 8, significant improvements versus placebo were observed in HAM-A psychic [quetiapine XR (both doses) and escitalopram] and somatic (quetiapine XR 150 mg/day and escitalopram) cluster scores and HAM-A response and remission rates (quetiapine XR 150 mg/day). Most common adverse events were dry mouth, somnolence and sedation (quetiapine XR), headache, and nausea (escitalopram). In patients with GAD, quetiapine XR (150 and 300 mg/day) demonstrated significant efficacy at week 8 with symptom improvement as early as day 4. We concluded that quetiapine XR safety and tolerability results were consistent with the known profile of quetiapine.
aAffiliated Research Institute Inc., San Diego, California
bDepartment of Psychiatry, University of Florida, and Florida Clinical Research Center, LLC, Florida
cAstraZeneca Pharmaceuticals, Wilmington, Delaware, USA
dAstraZeneca R&D, Södertälje, Sweden
Previously presented at: The 21st Congress of the European College of Neuropsychopharmacology, Barcelona, Spain, 30 August–3 September 2008 and The World Psychiatric Association International Congress, Florence, Italy, 1–4 April 2009.
Correspondence to Dr Charles Merideth, Affiliated Research Institute Inc., 8989 Rio, San Diego Drive Suite 350, San Diego, CA 92108, USA Tel: +1 619 688 6565; fax: +1 619 308 1766; e-mail: firstname.lastname@example.org
Received May 20, 2011
Accepted September 28, 2011