Examination of Tamoxifen in Acute Mania in Patients With Bipolar I Disorder
Status:
Completed
Trial end date:
2007-11-02
Target enrollment:
Participant gender:
Summary
The purpose of this study is to examine how the drug tamoxifen affects the brain in patients
with bipolar I disorder.
Bipolar Disorder (BD) is a severe, chronic, and often life-threatening illness for which safe
and effective treatments are necessary. The mood stabilizing effects of lithium and valproate
have revolutionized the treatment of patients with BD. However, a significant percentage of
patients do not respond fully to these drugs, and the biochemical basis for the antimanic and
mood-stabilizing actions of lithium and valproate is unclear. Both drugs inhibit protein
kinase C (PKC). There is a need to investigate the efficacy of a direct PKC inhibitor in the
treatment of acute mania. Tamoxifen is currently the only relatively selective PKC inhibitor
available for human use.
Participants in this study will be screened with a physical, psychiatric, and eye examination
and blood and urine tests. Eligible participants will be hospitalized at the Clinical Center
for at least 4 weeks. They will be tapered off all psychiatric medication and kept drug free
for 2 to 7 days. They will also be put on a low-monoamine, low-caffeine diet. Participants
will be randomly assigned to receive either tamoxifen or placebo (an inactive pill) for 3
weeks. During this time, participants will have daily pulse and blood pressure measurements,
several electrocardiograms (EKGs), and blood draws. Weight measurements will be taken at
least twice during the study, and caffeine or dextromethorphan will be given at the beginning
and end of the study to test how tamoxifen affects the way the body eliminates other
medications. Participants will have a physical examination at the end of the study.
At the end of this 4-week study, some participants may continue the study and will receive
tamoxifen for an additional 3 weeks. At the conclusion of the study, participants'
psychiatric status will be reassessed and long-term psychiatric treatment for their mood
disorders will be arranged.