Efficacy and tolerability of extended release quetiapine fumarate monotherapy in the acute treatment of generalized anxiety disorder: a randomized, placebo controlled and active-controlled study

Int Clin Psychopharmacol. 2012 Jan;27(1):40-54. doi: 10.1097/YIC.0b013e32834d9f49.


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.

Trial registration: ClinicalTrials.gov NCT00329446.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acute Disease
  • Adult
  • Anti-Anxiety Agents / adverse effects
  • Anti-Anxiety Agents / therapeutic use*
  • Anxiety Disorders / diagnosis
  • Anxiety Disorders / drug therapy*
  • Anxiety Disorders / psychology
  • Delayed-Action Preparations
  • Dibenzothiazepines / adverse effects
  • Dibenzothiazepines / therapeutic use*
  • Double-Blind Method
  • Female
  • Humans
  • Logistic Models
  • Male
  • Middle Aged
  • Placebos
  • Predictive Value of Tests
  • Psychiatric Status Rating Scales
  • Quetiapine Fumarate
  • Time Factors
  • Treatment Outcome
  • United States
  • Young Adult


  • Anti-Anxiety Agents
  • Delayed-Action Preparations
  • Dibenzothiazepines
  • Placebos
  • Quetiapine Fumarate

Associated data

  • ClinicalTrials.gov/NCT00329446