Continuation phase treatment outcomes for switching, combining, or augmenting strategies for treatment-resistant major depressive disorder: A VAST-D report.

BACKGROUND: This secondary analysis of the VA Augmentation and Switching Treatments for Depression study compared the continuation phase treatment outcomes of three commonly used second-step treatment strategies following at least one prior failed medication treatment attempt. METHODS: In total, 1522 outpatients with MDD were randomized to switching to bupropion-SR (S-BUP), combining with bupropion-SR (C-BUP), or augmenting with aripiprazole (A-ARI). Following 12 weeks of acute phase treatment, 725 entered the 24-week continuation treatment phase. Depressive symptom severity, relapse, "emergent" remission, anxiety, suicidal ideation, quality of life, health status, and side effects were compared. RESULTS: We did not find clinically significant differential treatment effects with the exception that A-ARI was associated with less anxiety than S-BUP or C-BUP. Participants who entered continuation treatment as remitters had milder depressive symptom severity and lower relapse rates than those not in remission; they also experienced more improvement on most other outcomes. A-ARI was associated with less anxiety, insomnia, and dry mouth but more somnolence, extrapyramidal effects, akathisia, abnormal laboratory values, and appetite and weight gain. CONCLUSIONS: Continuation treatment is a dynamic period. Regardless of the treatment, participants who entered continuation treatment at Week 12 in full remission continued to have better outcomes over the subsequent 24 weeks than those who were not in remission at the start of the continuation phase.

Effect of Antidepressant Switching vs Augmentation on Remission Among Patients With Major Depressive Disorder Unresponsive to Antidepressant Treatment: The VAST-D Randomized Clinical Trial.

IMPORTANCE: Less than one-third of patients with major depressive disorder (MDD) achieve remission with their first antidepressant. OBJECTIVE: To determine the relative effectiveness and safety of 3 common alternate treatments for MDD. DESIGN, SETTING, AND PARTICIPANTS: From December 2012 to May 2015, 1522 patients at 35 US Veterans Health Administration medical centers who were diagnosed with nonpsychotic MDD, unresponsive to at least 1 antidepressant course meeting minimal standards for treatment dose and duration, participated in the study. Patients were randomly assigned (1:1:1) to 1 of 3 treatments and evaluated for up to 36 weeks. INTERVENTIONS: Switch to a different antidepressant, bupropion (switch group, n = 511); augment current treatment with bupropion (augment-bupropion group, n = 506); or augment with an atypical antipsychotic, aripiprazole (augment-aripiprazole group, n = 505) for 12 weeks (acute treatment phase) and up to 36 weeks for longer-term follow-up (continuation phase). MAIN OUTCOMES AND MEASURES: The primary outcome was remission during the acute treatment phase (16-item Quick Inventory of Depressive Symptomatology-Clinician Rated [QIDS-C16] score ≤5 at 2 consecutive visits). Secondary outcomes included response (≥50% reduction in QIDS-C16 score or improvement on the Clinical Global Impression Improvement scale), relapse, and adverse effects. RESULTS: Among 1522 randomized patients (mean age, 54.4 years; men, 1296 [85.2%]), 1137 (74.7%) completed the acute treatment phase. Remission rates at 12 weeks were 22.3% (n = 114) for the switch group, 26.9% (n = 136)for the augment-bupropion group, and 28.9% (n = 146) for the augment-aripiprazole group. The augment-aripiprazole group exceeded the switch group in remission (relative risk [RR], 1.30 [95% CI, 1.05-1.60]; P = .02), but other remission comparisons were not significant. Response was greater for the augment-aripiprazole group (74.3%) than for either the switch group (62.4%; RR, 1.19 [95% CI, 1.09-1.29]) or the augment-bupropion group (65.6%; RR, 1.13 [95% CI, 1.04-1.23]). No significant treatment differences were observed for relapse. Anxiety was more frequent in the 2 bupropion groups (24.3% in the switch group [n = 124] vs 16.6% in the augment-aripiprazole group [n = 84]; and 22.5% in augment-bupropion group [n = 114]). Adverse effects more frequent in the augment-aripiprazole group included somnolence, akathisia, and weight gain. CONCLUSIONS AND RELEVANCE: Among a predominantly male population with major depressive disorder unresponsive to antidepressant treatment, augmentation with aripiprazole resulted in a statistically significant but only modestly increased likelihood of remission during 12 weeks of treatment compared with switching to bupropion monotherapy. Given the small effect size and adverse effects associated with aripiprazole, further analysis including cost-effectiveness is needed to understand the net utility of this approach. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01421342.