Aripiprazole augmentation of selective serotonin reuptake inhibitors for treatment-resistant major depressive disorder

Background: Due to their favorable side effect profile, atypical antipsychotic agents offer important therapeutic advantages in mood disorders. Aripiprazole, an atypical antipsychotic agent with partial dopaminergic and serotonin 1^A receptor agonist activity, may be particularly useful when used in conjunction with standard antidepressants in treatment-resistant depression. The purpose of this study was to test this hypothesis in depressed outpatients who have not experienced significant clinical improvement following an adequate trial of a selective serotonin reuptake inhibitor (SSRI). Method: 12 patients (mean ± SD age = 46.6 ± 11.3 years, 66.7% female) with major depressive disorder (MDD) diagnosed by use of the Structured Clinical Interview for DSM-IV-Axis I Disorders, who had failed to experience a clinical response following an adequate trial of an SSRI, were treated with open-label aripiprazole in addition to their SSRI for 8 weeks. Clinical response was defined as a 50% or greater decrease in depressive symptoms during the course of the trial (baseline-endpoint) as measured by the 17-item Hamilton Rating Scale for Depression total score. Data were collected from August 2003 to July 2004. Results: 9/12 (75.0%) patients completed the trial. Using a completer analysis, 5/9 (55.6%) patients were classified as responders. An intent-to-treat (ITT) analysis resulted in 7 responders (58.3%). The overall proportion of remitters was 3/9 (33.3%) using a completer analysis and 5/12 (41.7%) using the ITT analysis. Aripiprazole administration appeared safe, with no severe adverse events observed in any of the study participants. Conclusions: These results suggest a possible augmentation role for aripiprazole when used in conjunction with SSRIs in SSRI-resistant MDD.