Efficacy of Venlafaxine Extended-Release Capsules in Nondepressed Outpatients With Generalized Anxiety Disorder
Open Access
- 21 June 2000
- journal article
- clinical trial
- Published by American Medical Association (AMA) in JAMA
- Vol. 283 (23), 3082-3088
- https://doi.org/10.1001/jama.283.23.3082
Abstract
Context Generalized anxiety disorder (GAD) is a chronic disorder that is associated with debilitating psychic and somatic symptoms. Venlafaxine extended-release (XR) capsules have been shown to be effective in short-term treatment of patients with GAD without major depressive disorder (MDD), but long-term data are needed to establish whether this agent confers persistent benefits. Objective To compare the 6-month efficacy and safety of a flexible dosage of venlafaxine XR in outpatients with GAD without associated MDD. Design Six-month, randomized, double-blind, placebo-controlled, parallel-group trial conducted May 1996 to October 1997. Setting Fourteen outpatient clinics and private psychiatric practices in the United States. Participants A total of 251 outpatients aged 18 years or older who met Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV) criteria for GAD, had sufficient symptoms to require treatment, and did not have coexisting MDD. Interventions Participants were randomly assigned to receive either placebo (n=127) or venlafaxine XR (75, 150, or 225 mg/d, as required to control symptoms; n=124) for 28 weeks. Main Outcome Measures Changes from baseline in the Hamilton Rating Scale for Anxiety (HAM-A) total score, the HAM-A psychic anxiety factor score, and the Clinical Global Impressions (CGI) scale Severity of Illness and Global Improvement scores, compared by intervention group. Results During weeks 6 through 28, response rates in the venlafaxine XR group were 69% or higher compared with rates of 42% to 46% in the placebo group (P<.001). By an evaluable-patient analysis, venlafaxine XR compared with placebo significantly improved anxiety scores from week 1 or 2 through week 28 on all primary efficacy measures, including the HAM-A total (P<.001), the HAM-A psychic anxiety factor (P<.001), and the CGI scale scores (P<.001). Adjusted mean changes from baseline to week 28 using last-observation-carried-forward methods were for HAM-A, venlafaxine XR −13.4, placebo −8.7 (P<.001); for HAM-A psychic anxiety score, venlafaxine XR −7.4, placebo −4.2 (P<.001); and for CGI-Improvement, venlafaxine XR 2.2, placebo 3.0 (P<.001). The most common treatment-emergent adverse event was nausea, followed by somnolence and dry mouth. Conclusions This study is the first placebo-controlled demonstration of the long-term efficacy of any drug class in treating outpatients with DSM-IV–diagnosed GAD. Venlafaxine XR is an effective, rapidly acting, safe, once-daily agent for both the short- and long-term treatment of anxiety and may provide an important alternative to currently available anxiolytics.Keywords
This publication has 12 references indexed in Scilit:
- Generalized Anxiety DisorderAnnals of Internal Medicine, 2019
- Impairment in Pure and Comorbid Generalized Anxiety Disorder and Major Depression at 12 Months in Two National SurveysAmerican Journal of Psychiatry, 1999
- Efficacy of once-daily venlafaxine extended release (XR) for symptoms of anxiety in depressed outpatientsJournal of Affective Disorders, 1998
- Mental Disorders and Disability Among Patients in a Primary Care Group PracticeAmerican Journal of Psychiatry, 1997
- The Nature of Generalized Anxiety Disorder and Pathological Worry: Current Evidence and Conceptual ModelsThe Canadian Journal of Psychiatry, 1997
- Phenomenology and Course of Generalised Anxiety DisorderThe British Journal of Psychiatry, 1996
- Epidemiology and comorbidity of anxiety disorders in the elderlyAmerican Journal of Psychiatry, 1994
- Quality of life and psychiatric morbidity in panic disorder and generalized anxiety disorderAmerican Journal of Psychiatry, 1993
- Anxiety Disorders:Journal of Psychotherapy & The Family, 1988
- Generalized anxiety and generalized anxiety disorder: description and reconceptualizationAmerican Journal of Psychiatry, 1986