Desvenlafaxine vs. Placebo Treatment of Chronic Depression
Condition: Dysthymic Disorder; Dysthymia; Chronic Depressive Disorder
MeSH terms: Depression; Depressive Disorder; Dysthymic Disorder
Study type: Interventional
Phase: Phase 4

Summary: 
      The investigators are studying a new antidepressant medicine, desvenlafaxine, for the
      treatment of people with chronic depression. Desvenlafaxine (trade name Pristiq) has been
      approved by the FDA for the treatment of major depression.

      The investigators are testing whether this medicine is also effective for adults with a type
      of chronic depression that is less severe than major depression. This condition is also known
      as dysthymic disorder or dysthymia. Chronic depression, lasting two or more years, often
      causes significant suffering and impairment.

      In addition, the investigators are using MRI imaging, which uses magnetic signals to make
      pictures of the brain's structure and also of its functioning. The purpose of MRI imaging in
      this study is to see whether chronic depression is associated with differences in brain
      structure or functioning, and whether such differences change after medication or placebo
      treatment. To test this MRI scans are done at the start of the study and after 12 weeks of
      medication or placebo treatment. Getting MRI imaging will be an option for participants in
      this study but is not required.

      This study involves a 6 to 12 week double-blind period during which half of the participants
      will take the new medication and half will take a placebo (an inactive look-alike pill).
      After the double blind phase, all subjects can be treated for 12 weeks with an FDA-approved
      antidepressant medication.

      Assessments (of depressive symptoms, social functioning, and personality) will be done by
      study staff and by patients before the study starts, at each study visit for the first 12
      weeks, and again after 24 weeks in the study.
    

Detailed description: 
      The investigators wish to study acute efficacy for 12 weeks on a double blind basis and
      continued response after open-label treatment at week 24 follow-up. It is important to
      establish the acute (12 week) efficacy of desvenlafaxine in non-major chronic depression.
      Also, given that non-major chronic depression is by definition chronic, it is important to
      demonstrate that benefit persists at follow-up assessment (24 weeks); this is clinically
      important in trying to alleviate the significant psychosocial morbidity associated with this
      disorder.

      The investigators believe this study will have significant value in the treatment of patients
      with non-major chronic depression, and will add significantly to what remains an extremely
      small scientific literature.

      The investigators would also like to study the effects of desvenlafaxine on brain structure
      and function. Learning that a medication reduces symptoms does not teach us how the
      medication achieves this outcome. Participants in this study can have the opportunity to
      participate in MRI scanning that will help to understand the mechanisms by with
      desvenlafaxine is effective. MRI scans are done prior to starting the clinical trial and then
      again after completing the double blind clinical trial.
    

Intervention name(s): Desvenlafaxine; Placebo
Intervention type(s): Drug; Drug
Intervention description(s): Desvenlafaxine oral dose ranging from 50 to 100 mg/day; Matching placebo pills
Other intervention name(s): Pristiq; Inactive comparator
Intervention MeSH terms: Desvenlafaxine Succinate
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Dysthymic disorder; Dysthymia; Chronic non-major depression; Non-major chronic depression; Chronic depressive disorder; Antidepressant treatment