Effectiveness of Long-Term Versus Short-Term Treatment of Generalized Anxiety Disorder With Venlafaxine XR

This study has been completed.
Sponsor:
Information provided by:
National Institute of Mental Health (NIMH)
ClinicalTrials.gov Identifier:
NCT00183274
First received: September 12, 2005
Last updated: October 12, 2010
Last verified: September 2008

September 12, 2005
October 12, 2010
January 2004
September 2009   (final data collection date for primary outcome measure)
Relapse of GAD [ Time Frame: Meausured at Months 6, 12, and 24 ] [ Designated as safety issue: No ]
Relapse: Relapse of GAD at Months 6, 12, and 24
Complete list of historical versions of study NCT00183274 on ClinicalTrials.gov Archive Site
Anxiety, depression, and GAD symptoms [ Time Frame: Measured at Months 6, 12, 18, and 24 ] [ Designated as safety issue: No ]
Anxiety, Depression, GAD symptoms at Months 6, 12, and 24
Not Provided
Not Provided
 
Effectiveness of Long-Term Versus Short-Term Treatment of Generalized Anxiety Disorder With Venlafaxine XR
Short-term Versus Long-term Treatment in Generalized Anxiety Disorder

This study will assess the effectiveness of venlafaxine XR in preventing the relapse of generalized anxiety disorder after 6 months of treatment versus 12 months of treatment.

Generalized anxiety disorder (GAD) is a highly prevalent, chronic psychiatric disorder. Despite the fact that GAD frequently demands prolonged treatment with medication, very little is known about the benefits of long-term treatment. GAD is characterized by 6 months or more of exaggerated worry and tension that is unfounded or much more severe than the normal anxiety most people experience. People with GAD are unable to relax and often suffer from insomnia. Venlafaxine XR, a drug used to treat depression, has been shown to be effective in the short-term treatment of GAD. However, its benefits over a course of more than 8 weeks have not been assessed. This study will evaluate the effectiveness of venlafaxine XR in treating GAD on a long-term basis and preventing the relapse of GAD after 6 months of treatment versus 12 months of treatment.

Participants in this double-blind study will first receive 6 months of open-label treatment with venlafaxine XR. Upon completion of this initial phase, participants will be randomly assigned to either continue on venlafaxine XR or begin taking placebo. After 12 months, participants taking venlafaxine XR will be randomly assigned to continue on the drug or switch to placebo. Participants will have 22 study visits over at least 18 months. Follow-up visits will occur 24 months after enrollment. Relapse of GAD will be assessed with the Hamilton Anxiety Scale and Global Severity and Improvement Scale. A variety of methods, including questionnaires and standardized scales, will be used to assess secondary outcomes.

Interventional
Phase 4
Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Parallel Assignment
Masking: Double Blind (Subject, Caregiver, Investigator, Outcomes Assessor)
Primary Purpose: Treatment
Anxiety Disorders
  • Drug: Venlafaxine XR
    All participants will take venlafaxine for 6 months. After this initial 6 months, participants who are not randomized to placebo will continue to take venlafaxine.
  • Drug: Placebo
    After initial treatment with venlafaxine, some participants will be randomized to take placebo for 6 months in the second phase of the study and then to switch back to venlafaxine or continue with placebo for an additional 6 months.
  • Experimental: 1
    Venlafaxine
    Intervention: Drug: Venlafaxine XR
  • Experimental: 2
    Venlafaxine and placebo
    Interventions:
    • Drug: Venlafaxine XR
    • Drug: Placebo

*   Includes publications given by the data provider as well as publications identified by ClinicalTrials.gov Identifier (NCT Number) in Medline.
 
Completed
330
September 2009
September 2009   (final data collection date for primary outcome measure)

Inclusion Criteria:

  • GAD diagnosis by structured interview
  • Hamilton Anxiety Scale score of 18 or MORE
  • Clinical Global Impressions Severity Scale score of at least 4
  • Hamilton Depression Scale score of 18 or less
  • Hamilton Depression Scale suicide item score less than 2
  • Use of an effective form of contraception throughout the study

Exclusion Criteria:

  • Hypersensitivity to venlafaxine XR
  • History of seizures
  • Episode of major depressive disorder in the previous 6 months
  • History of any psychotic illness, bipolar disorder, or dementia
  • Substance abuse and dependence during the past 6 months
  • Other anxiety disorders with the exception of social phobia as long as GAD is primary
  • Regular use of anxiolytics or antidepressants within 7 days of study onset
  • Use of fluoxetine or monoamine oxidase inhibitors within 28 days of study onset (low dose usage of benzodiazepines will not prevent participation)
  • Use of other psychotropic medication besides benzodiazepines during the study
Both
18 Years and older
No
Contact information is only displayed when the study is recruiting subjects
United States
 
NCT00183274
R01 MH65963, DSIR 83-ATAS
Yes
Karl Rickels, MD, University of Pennsylvania
National Institute of Mental Health (NIMH)
Not Provided
Principal Investigator: Karl Rickels, MD University of Pennsylvania
National Institute of Mental Health (NIMH)
September 2008

ICMJE     Data element required by the International Committee of Medical Journal Editors and the World Health Organization ICTRP