Objective: To assess the efficacy of duloxetine 60 mg/day in the prevention of depressive recurrence in patients with major depressive disorder (MDD).
Methods: Patients having at least three episodes of MDD in the past 5 years received open-label (OL) duloxetine 60–120 mg/day for up to 34 weeks. Patients meeting response criteria were then randomised to either duloxetine or placebo for up to 52 weeks of double-blind maintenance treatment. Only patients taking duloxetine 60 mg/day during the OL phase, and randomised to either duloxetine (remained on 60 mg/day dose) or placebo, were included in this post hoc analysis. The primary outcome measure was time to recurrence of a major depressive episode. The 17-item Hamilton Rating Scale for Depression (HAMD17) was used to evaluate depressive symptomatology. Global and physical functioning and pain were also assessed. Safety and tolerability were assessed via analysis of treatment-emergent adverse events (TEAEs), vital signs and weight.
Results: A total of 124 patients were randomised to duloxetine 60 mg/day (n = 64) or placebo (n = 60). Time to depressive recurrence was significantly longer in duloxetine-treated patients compared with placebo-treated patients (p = 0.001). During the double-blind maintenance phase, 31.7% of placebo-treated patients experienced a depressive recurrence compared with 12.5% of duloxetine-treated patients (p = 0.004). The HAMD17 total score and most of its subscales as well as the Clinical Global Impression of Severity (CGI-S), significantly worsened in the placebo group compared with the duloxetine 60 mg/day group. There were no significant differences between treatment groups in TEAEs, discontinuations because of adverse events, vital signs or weight.
Conclusions: Treatment with duloxetine 60 mg/day was associated with a longer time to depressive recurrence and a significantly lower recurrence rate compared with placebo.