Related Experiment Video
Updated: Apr 14, 2026

Developing a Rat Model for Bipolar Disorder
Published on: May 2, 2025
A 13-week, randomized double-blind, placebo-controlled, cross-over trial of ziprasidone in bipolar spectrum disorder
Ashwin A Patkar1, Chi-Un Pae, Paul A Vöhringer
1From the *Department of Psychiatry, Duke University Medical Center, Durham, NC; †Mood Disorders Program, Department of Psychiatry, Tufts Medical Center, Boston, MA; ‡Hospital Clinico, Facultad de Medicina, Universidad Chile, Santiago, Chile; §Department of Neuropsychiatry and Behavioral Science University of South Carolina-Columbia; ∥Sunovion Pharmaceuticals, Fort Lee, NJ; and ¶Tufts University School of Medicine, Boston, MA.
Objective:
Features of bipolarity in a major depressive disorder sample were used to define a "bipolar spectrum disorder" population for treatment with a neuroleptic agent, ziprasidone.
Methods:
Forty-nine acutely depressed patients were randomized to ziprasidone-washout-placebo or placebo-washout-ziprasidone in this double-blind, prospective, 13-week crossover trial. All patients met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, criteria for a major depressive episode and were positive for at least 3 predictors of bipolarity: family history of bipolar disorder, antidepressant-induced mania, highly recurrent depressive episodes (>5), atypical depression, early onset of depression (
Results:
There was a small statistically nonsignificant benefit with ziprasidone compared with placebo on Montgomery Asberg Depression Rating Scale change [-1.5 (p = 0.48)]. Statistical carryover effects were observed.
Conclusions:
Ziprasidone, alone or added to antidepressants, was not more effective than placebo in this population. A false-negative finding due to the crossover design is suggested by statistical carryover effects. Alternatively, this definition of bipolar spectrum illness may have been too nonspecific to show neuroleptic benefit, unlike other definitions, like "mixed depression." Also, this study did not test potential neuroleptic efficacy without the potentially mood-destabilizing effects of antidepressants.
Related Concept Videos
Psychosis: Goals of Pharmacotherapy
Bipolar Disorder
Mania and Antimanic Drugs: Overview
Blinding
Crossover Experiments
Crossover designs are performed even with smaller sample sizes since the samples can act as their controls. These are better than simple randomized trials since patients are exposed to all the treatments.
Psychosis and Antipsychotic Drugs: Overview

