title: Extended-release quetiapine fumarate (quetiapine XR) as adjunctive therapy in patients with generalized anxiety disorder and a history of inadequate treatment response: a randomized, double-blind study.
abstract: BACKGROUND
  For many patients with generalized anxiety disorder (GAD), first-line treatment does not lead to remission. This study investigated the efficacy and tolerability of adjunctive extended-release quetiapine fumarate (quetiapine XR) in patients with GAD and an inadequate response to selective serotonin reuptake inhibitors (SSRIs) and serotonin-norepinephrine reuptake inhibitors (SNRIs).
  
  
  METHODS
  Patients were randomized to quetiapine XR or placebo adjunctive to SSRI/SNRIs in an 11-week study. The primary endpoint was change from randomization to week 8 in Hamilton Anxiety Rating Scale (HAM-A) total score. Secondary variables were HAM-A psychic/somatic clusters, response, and remission, and Clinical Global Impression–Severity of Illness (CGI-S) score.
  
  
  RESULTS
  A total of 409 patients received quetiapine XR (n=209) or placebo (n=200). The week 8 mean change in HAM-A total score was not statistically significant for quetiapine XR (–10.74; P=.079) vs placebo (–9.61). Secondary variables were generally consistent with the primary analysis, except for a significant reduction in HAM-A total score (week 1) and significant improvements in HAM-A psychic cluster and CGI-S total scores (week 8). Adverse events included dry mouth, somnolence, sedation, headache, and dizziness.
  
  
  CONCLUSIONS
  In patients with GAD and an inadequate response to SSRI/SNRIs, adjunctive quetiapine XR did not show a statistically significant effect for the primary endpoint at week 8, although some secondary endpoints were statistically significant vs placebo. Quetiapine XR was generally well tolerated.
authors.forename: Arifulla
authors.initials: A
authors.lastname: Khan
authors.forename: Sarah
authors.initials: S
authors.lastname: Atkinson
authors.forename: Irina
authors.initials: I
authors.lastname: Mezhebovsky
authors.forename: Fahua
authors.initials: F
authors.lastname: She
authors.forename: Todd
authors.initials: T
authors.lastname: Leathers
authors.forename: Sanjeev
authors.initials: S
authors.lastname: Pathak
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D001008:Anxiety Disorders / Q000188:drug therapy*; D003692:Delayed-Action Preparations; D003987:Dibenzothiazepines / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D004311:Double-Blind Method; D004357:Drug Synergism; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D014179:Neurotransmitter Uptake Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D011569:Psychiatric Status Rating Scales; D000069348:Quetiapine Fumarate; D017367:Selective Serotonin Reuptake Inhibitors / Q000008:administration & dosage / Q000494:pharmacology; D012720:Severity of Illness Index; D016896:Treatment Outcome
chemical_list: D014150:Antipsychotic Agents; D003692:Delayed-Action Preparations; D003987:Dibenzothiazepines; D014179:Neurotransmitter Uptake Inhibitors; D000069348:Quetiapine Fumarate; D017367:Selective Serotonin Reuptake Inhibitors