A Multicenter, Randomized, Double-Blind, Placebo-Controlled, Parallel Group Study To Evaluate The Efficacy And Safety Of DVS-233 SR For Prevention Of Depressive Relapse In Adult Outpatients With Major Depressive Disorder

Primary Objective: To compare the efficacy and safety of DVS-233 SR versus placebo treatment
in reducing the relapse rate of depressive symptoms in subjects with major depressive
disorder (MDD), and to compare the percentages of relapse in terms of time to relapse between
DVS-233 SR and placebo treatment groups by using survival analysis.

Secondary Objective: To assess the response of subjects on DVS-233 SR versus placebo for the
clinical global evaluation, functionality, general well-being, pain, and absence of symptoms
(Hamilton Psychiatric Rating Scale for Depression, 17-item [HAM-D17] < 7).