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Determine The Percentage Of Depressed Outpatients Who Do Not Effectively Metabolize Extended-release Venlafaxine HCl

This study has been completed.
Information provided by:
Wyeth is now a wholly owned subsidiary of Pfizer Identifier:
First received: November 7, 2008
Last updated: January 5, 2011
Last verified: January 2011
This is a study to determine the percentage of patients with depression who are treated with extended-release venlafaxine HCl (U.S. marketed brand Effexor XR®) who are Poor Metabolizers (based on the levels of the drug in the blood) at 2D6 (a system in the liver that breaks down some medications and other chemicals).

Condition Intervention Phase
Depression Procedure: blood draw Phase 4

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Health Services Research
Official Title: An Open-Label Study To Evaluate The Prevalence Of Phenotypic Poor Metabolizers At CYP2D6 Among Venlafaxine-Treated Outpatients With Depression

Resource links provided by NLM:

Further study details as provided by Wyeth is now a wholly owned subsidiary of Pfizer:

Primary Outcome Measures:
  • 0-desmethyl venlafaxine/venlafaxine ratio (levels of the drug in the blood) [ Time Frame: 1 day ]

Secondary Outcome Measures:
  • Determine the percentage of patients treated with extended-release venlafaxine HCl who are genotypic Poor Metabolizers. [ Time Frame: 1 day ]

Enrollment: 971
Study Start Date: October 2008
Study Completion Date: July 2009
Primary Completion Date: July 2009 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
1 Procedure: blood draw
Test Article was not provided to subjects for this study.


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Men and women subjects aged 18 years or older.
  • Current outpatient treatment with extended-release venlafaxine HCl (U.S. marketed brand Effexor XR®), within the US Food and Drug Administration (FDA)-approved dosage range for depression (37.5 mg/day to 225 mg/day), for 8 weeks or less.
  • Ability to have a blood draw within 4 to 12 hours of the most recent dose of Effexor XR®.

Exclusion Criteria:

  • Determination by the investigator that a blood draw is contraindicated.
  • Participation in an investigational study within the past 30 days where the study medication is not known.
  • Previous treatment with Effexor XR® or extended-release venlafaxine HCl (generic) in the 6 months prior to current treatment regimen.
  • Treatment with DVS SR within the last 30 days.
  Contacts and Locations
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Please refer to this study by its identifier: NCT00788944

  Show 53 Study Locations
Sponsors and Collaborators
Wyeth is now a wholly owned subsidiary of Pfizer
Study Director: Pfizer Call Center Pfizer
  More Information

Additional Information:
Publications automatically indexed to this study by Identifier (NCT Number):
Responsible Party: Director, Clinical Trial Disclosure Group, Pfizer, Inc Identifier: NCT00788944     History of Changes
Other Study ID Numbers: 0600B1-4433
Study First Received: November 7, 2008
Last Updated: January 5, 2011

Additional relevant MeSH terms:
Depressive Disorder
Behavioral Symptoms
Mood Disorders
Mental Disorders
Venlafaxine Hydrochloride
Serotonin and Noradrenaline Reuptake Inhibitors
Neurotransmitter Uptake Inhibitors
Membrane Transport Modulators
Molecular Mechanisms of Pharmacological Action
Neurotransmitter Agents
Physiological Effects of Drugs
Antidepressive Agents, Second-Generation
Antidepressive Agents
Psychotropic Drugs processed this record on June 23, 2017