Duloxetine-bupropion combination for treatment-resistant atypical depression: A double-blind, randomized, placebo-controlled trial

The efficacy, safety, and tolerability of combined bupropion versus placebo using duloxetine as active reference drug, in patients with a DSM-IV diagnosis of major depression with atypical features and a history of treatment resistance, were evaluated in this preliminary six-week study. Patients (n=46) had a baseline Hamilton Depression Scale (HAM-D) ≥14 and were randomly assigned to 150/300. mg/day bupropion vs. placebo, which was added to 60 to 120. mg/day duloxetine depending on baseline depression severity. Atypical features of depression were assessed using the additional eight-item module of the Structured Interview Guide for the HAM-D with the Atypical Depression Supplement. By week 6, only five (21.7%) patients receiving duloxetine+placebo vs. six (26.1%) patients on the bupropion combination achieved response. No significant difference in final HAM-D scores between the two groups was observed between those patients achieving response. The presence of a higher number of atypical features significantly predicted non-response, with the relevant binary logistic regression model correctly classifying 17 out 22 (77.3%) of non-responders [Exp(B)=0.294; p=0.016] vs. 17 out 23 (73.9%) [Exp(B)=0.353; p=0.028] non-responder cases in the "+placebo" and "+bupropion" groups, respectively. In those patients receiving bupropion, treatment-emergent adverse events leading to withdrawal were more common among those receiving lower doses of the combination drug, and no life-threating dangers were noted. Additional studies, including an adequate course of duloxetine trial, are nonetheless aimed to allow a firm conclusion about the usefulness of the combination of duloxetine and bupropion for treatment-resistant cases of major depression with atypical features.