This multicenter, randomized, double-blind, placebo-controlled, active-referenced (duloxetine 60 mg), parallel-group study evaluated the short-term efficacy and safety of vortioxetine (10–20 mg) on cognitive function in adults (aged 18–65 years) diagnosed with major depressive disorder (MDD) who self-reported cognitive dysfunction. Efficacy was evaluated using ANCOVA for the change from baseline to week 8 in the digit symbol substitution test (DSST)–number of correct symbols as the prespecified primary end point. The patient-reported perceived deficits questionnaire (PDQ) and physician-assessed clinical global impression (CGI) were analyzed in a prespecified hierarchical testing sequence as key secondary end points. Additional predefined end points included the objective performance-based University of San Diego performance-based skills assessment (UPSA) (ANCOVA) to measure functionality, MADRS (MMRM) to assess efficacy in depression, and a prespecified multiple regression analysis (path analysis) to calculate direct vs indirect effects of vortioxetine on cognitive function. Safety and tolerability were assessed at all visits. Vortioxetine was statistically superior to placebo on the DSST (P<0.05), PDQ (P<0.01), CGI-I (P<0.001), MADRS (P<0.05), and UPSA (P<0.001). Path analysis indicated that vortioxetine's cognitive benefit was primarily a direct treatment effect rather than due to alleviation of depressive symptoms. Duloxetine was not significantly different from placebo on the DSST or UPSA, but was superior to placebo on the PDQ, CGI-I, and MADRS. Common adverse events (incidence ⩾5%) for vortioxetine were nausea, headache, and diarrhea. In this study of MDD adults who self-reported cognitive dysfunction, vortioxetine significantly improved cognitive function, depression, and functionality and was generally well tolerated.

ClinicalTrials.gov identifier: NCT00735709.

In this study of adults with MDD treated for 8 weeks with vortioxetine 2.5 mg or 5 mg per day, reductions in depression symptoms were not statistically significant compared with placebo. Study limitations are discussed, including patient characteristics, MDD severity, drug dosing, and aspects of trial design. Both doses of vortioxetine were well tolerated. This trial has been registered at clinicaltrials.gov #NCT00672620.

Vortioxetine (Lu AA21004) is a multi-modal antidepressant in clinical development for the treatment of major depressive disorder (MDD). The current study evaluated the efficacy and tolerability of 5 mg vortioxetine compared to placebo after 6 wk of treatment in adults with MDD in an out-patient setting. Adults aged 18-75 yr, with a diagnosis of MDD and a baseline Montgomery-Asberg Depression Rating Scale (MADRS) total score ≥30, were randomized to receive either 5 mg vortioxetine or placebo over 6 wk, followed by a 2-wk medication-free discontinuation period. The primary efficacy measure was change from baseline in Hamilton Rating Scale for Depression (HAMD)-24 total score at week 6 compared to placebo. Additional measures included response and remission rates, Clinical Global Impression Scale - Improvement scores, HAMD-24 total score in subjects with baseline Hamilton Anxiety Scale (HAMA) >19 and MADRS-S total score. Adverse events (AEs) were assessed throughout the study. A total of 600 adults were randomized. There were no significant differences in efficacy measures between subjects in the 5 mg vortioxetine and placebo groups at week 6. HAMD-24 total score in subjects with baseline HAMA >19 in the 5 mg vortioxetine group was improved at weeks 3-6 compared to the placebo group (nominal p value <0.05). The most common AEs for the vortioxetine and placebo groups were nausea (19.1 and 9.4%), headache (17.1 and 15.1%) and diarrhoea (11.4 and 7.0%), respectively. In this study of adults with MDD, 5 mg vortioxetine did not differ significantly from placebo in reducing depression symptoms after 6 wk of treatment.