Randomized, double‐blind, placebo‐controlled study to assess the efficacy and safety of vortioxetine in Japanese patients with major depressive disorder

AIM: The burden of major depressive disorder (MDD) in Japan is high. This study aimed to evaluate the efficacy and safety of the multimodal antidepressant vortioxetine in Japanese patients with MDD. METHODS: Japanese patients aged 20–75 years with recurrent MDD and a Montgomery–Åsberg Depression Rating Scale (MADRS) score ≥ 26 were randomized to vortioxetine 10 or 20 mg or placebo in a phase‐3, double‐blind, 8‐week study. The primary end‐point was change in MADRS total score from baseline. Secondary end‐points included MADRS response and remission rates, change in Hamilton Rating Scale for Depression‐17 item (HAM‐D17) score, and other measures of depressive symptoms, including Clinical Global Impression of Severity (CGI‐S), Clinical Global Impression of Improvement (CGI‐I), and Sheehan Disability Scale (SDS). Cognitive function was assessed using Digit Symbol Substitution Test (DSST) score and Perceived Deficits Questionnaire‐5 item (PDQ‐5) score. RESULTS: Vortioxetine 10 mg (n = 165) and 20 mg (n = 163) reduced MADRS total score by 2.66 and 3.07 points versus placebo (n = 161) after 8 weeks (P < 0.01 for each dose), respectively. MADRS response and remission rates were also significantly greater with vortioxetine than with placebo (P < 0.05 for both doses). Vortioxetine 10 and 20 mg significantly improved HAM‐D17 score, CGI‐I score, and SDS total score after 8 weeks. PDQ‐5 score was significantly improved in subjects administered vortioxetine, while DSST scores showed no significant difference. Vortioxetine was generally well tolerated. CONCLUSION: Vortioxetine at both the 10‐ and 20‐mg/day doses demonstrated robust antidepressant efficacy in Japanese patients with MDD, and was well tolerated over the 8‐week treatment period.