Adjunctive aripiprazole for depression: predictive value of early assessment

To determine whether early symptom improvement with adjunctive aripiprazole in major depressive disorder (MDD) predicts overall symptom remission.

Post hoc pooled analysis of 3 randomized, double-blind studies evaluating efficacy, safety, and tolerability of adjunctive aripiprazole or placebo with standard antidepressant therapy (ADT) in inadequate responders to a prospective 8-week ADT and at least 1 historical ADT.

A multivariate logistic regression model was developed to determine factors predicting remission most strongly at the end point. Remission was defined as a Montgomery-Asberg Depression Rating Scale (MADRS) total score of 10 or less at end point.

Early improvement in depression symptoms was the most significant predictor of remission. In adjunctive aripiprazole and placebo groups, improvement of 20% or more in MADRS total score (week 2) was a significant predictor of remission. At week 2, high sensitivity and high negative predictive values (NPVs) were reported for remission in both treatment arms. In the adjunctive aripiprazole arm, early improvement predicted later MADRS remission with high sensitivity (88.0%) and a high NPV (91.5%). Positive predictive value was moderate in both the adjunctive aripiprazole (45.4%) and placebo (37.5%) arms; specificity was 55.0% with adjunctive aripiprazole and 71.5% with placebo.

Week 2 was a clinically meaningful time point to identify early improvers, and lack of improvement early in treatment was a highly significant predictor of lack of later remission. Early assessment of changes in symptoms could prove useful in clinical practice and more appropriately target healthcare costs.