Relapse prevention in adults with major depressive disorder treated with vilazodone: a randomized, double-blind,...

This randomized withdrawal study assessed relapse prevention with vilazodone in adults with major depressive disorder. After 20 weeks of open-label treatment with vilazodone 40 mg/day, responders were randomized (1 : 1 : 1) to 28 weeks of double-blind, fixed-dose treatment with vilazodone 20 mg/day, vilazodone 40 mg/day, or placebo. The primary efficacy endpoint was time to first relapse, defined as Montgomery-Åsberg Depression Rating Scale total score of at least 18 and meeting major depressive episode criteria, Montgomery-Åsberg Depression Rating Scale total score of at least 18 at two consecutive visits, or discontinuation for an insufficient therapeutic response. Of 1204 patients who received open-label treatment, 564 completed treatment and were randomized (placebo=192, vilazodone 20 mg/day=185, vilazodone 40 mg/day=187). No significant difference was detected in time to relapse during the double-blind period (P>0.05). The crude percentage of patients that relapsed was similar between treatment groups (placebo=12.6%; vilazodone 20 mg/day=11.4%; vilazodone 40 mg/day=13.4%). The most common treatment-emergent adverse events were diarrhea (29.6%), nausea (24.0%), and headache (14.0%) during open-label treatment and headache (8.9%), nasopharyngitis (8.4%), and diarrhea (7.5%) during double-blind treatment in the combined vilazodone groups (20 and 40 mg/day). In conclusion, time to relapse with vilazodone was not statistically different from placebo. Vilazodone was generally well tolerated in adults with major depressive disorder.