LAUSR

BACKGROUND Maintenance therapy for major depressive disorder (MDD) is typically recommended at the dose on which the patient was stabilized. However, for some patients, dose alteration may be required. We investigated multiple vortioxetine doses versus placebo for relapse prevention in patients achieving remission with vortioxetine 10 mg daily. METHODS In this US-based, randomized withdrawal study, outpatients (N=1106, aged 18-75 years) with recurrent MDD (Montgomery-Åsberg Depression Rating Scale [MADRS] score ≥26), a current major depressive episode (MDE) (8 weeks-18 months' duration), and ≥2 previous MDEs were treated with open-label vortioxetine 10 mg once daily orally for 16 weeks. Responders at week 8 (≥50% MADRS score reduction) achieving remission (MADRS score ≤12) at weeks 14 and 16 (N=580) were randomized to vortioxetine 5, 10, or 20 mg or placebo in a 32-week double-blind period. The primary outcome was time to first relapse over the first 28 weeks; secondary outcomes (relapse, change in total MADRS, Clinician Global Impression-Severity [CGI-S]) were evaluated at 32 weeks. RESULTS Time to relapse was longer and cumulative relapse rates were lower for vortioxetine 5 mg (19.3%), 10 mg (17.9%), and 20 mg (17.4%) versus placebo (32.5%) over 28 weeks (p<0.05 for all). CGI-S scores remained stable and adverse events were generally mild-to-moderate. LIMITATIONS Extrapolation of results to patients achieving remission with vortioxetine doses other than 10 mg should be made with caution. CONCLUSION For patients with MDD achieving symptomatic remission at 10 mg/day, all doses of vortioxetine were effective for relapse prevention, with acceptable tolerability.