Abstract
AIM: Anhedonia in major depressive disorder may be resistant to first-line antidepressants. We examined the effect of vortioxetine, a multimodal antidepressant, on anhedonia-like symptoms in Japanese patients with major depressive disorder. METHODS: This was a post hoc analysis of an 8-week, randomized, double-blind, placebo-controlled, phase 3 study of vortioxetine (10 mg or 20 mg) in Japanese patients aged 20-75 years with recurrent major depressive disorder and a Montgomery-Åsberg Depression Rating Scale (MADRS) total score of at least 26. The primary outcome was the mean change from baseline to week 8 in anhedonia-like symptoms as measured by MADRS anhedonia factor score, composed of: Q1, apparent sadness; Q2, reported sadness; Q6, concentration; Q7, lassitude; and Q8, inability to feel. Mean change in MADRS total score and anhedonia factor score were compared among treatment groups, with data categorized by median baseline anhedonia factor score (0-17 or ≥18). RESULTS: Data were available for 489 patients. The least-squares mean difference in MADRS anhedonia factor score change from baseline to week 8 versus placebo was -1.34 for vortioxetine 10 mg (P = 0.0300) and -1.77 for vortioxetine 20 mg (P = 0.0044). The least-squares mean difference between vortioxetine and placebo in MADRS total score change from baseline to week 8 was -3.11 (10 mg dose) and -3.37 (20 mg dose) for patients with a higher baseline anhedonia factor score (≥18), and -2.08 (10 mg) and -2.61 (20 mg) for patients with a lower baseline score (0-17). CONCLUSION: This post hoc analysis suggests that vortioxetine may have therapeutic potential in patients with anhedonia-like symptoms of major depressive disorder. ClinicalTrials.gov identifier for primary study: NCT02389816.