Controlled-release Paroxetine in Major Depressive Disorder (Double-blind, Placebo-controlled Study)

Inclusion Criteria

Only the patients who meet all of the following conditions at Week -1 (at the start of placebo run-in phase) will be enrolled in this study. The hospitalization status will be no object. and Gender: No object.

• Target disease: Patients diagnosed as having one of the following depressive disorders based on DSM-IV-TR classification in conjunction with M.I.N.I. (The Mini International Neuropsychiatric Interview, Japanese version 5.0.0. [2003]) and showing currently a symptom of depression or depressed sate
• Major depressive disorder, single episode (296.2) (excluding those accompanied by comorbid psychiatric disorders)
• Major depressive disorder, recurrent (296.3) (excluding those accompanied by comorbid psychiatric disorders)
• Age: >= 20 years (at the time of obtaining consent)
• Consent: Patients from whom written consent to participate in this study can be obtained
• Gender:
• Female patients of childbearing potential can be enrolled. But, such patients who can be enrolled are limited to only those who are negative in the pregnancy test performed at the start of the placebo run-in phase and who agree to receive a pregnancy test at the time point defined in the study period and surely perform any of the contraceptive methods.
• Male subjects must abstain from (or use a condom during) sexual intercourse with a pregnant or lactating female. Male subjects must abstain from or use a condom plus spermicidal agent (foam/gel/film/cream/suppository) during sexual intercourse with a female of child-bearing potential.
• Patients whose HAM-D (17 items) total score is >= 20 points
• Patients whose duration of current episode at least 12 weeks but no longer than 24 months
• Patients whose score of "depressed mood" (HAM-D Item 1) is >= 2 points
• QTc Only the patients who meet all of the following conditions at Week -1 (at the start of the placebo run-in phase) and Week 0 (at the start of treatment phase) can be shifted to the treatment phase.
• Patients whose HAM-D (17 items) total score is >=20 points
• Patients whose score of "depressed mood" (HAM-D Item 1) is >=2 points

Exclusion Criteria

The patients who are meeting any of the following conditions at Week -1 (at the start of placebo run-in phase) must not be enrolled in this study.

• Patients whose primary diagnosis is a disorder classified to Axis I other than major depressive disorder in DSM-IV-TR classification (dysthymic disorder, eating disorder, specific phobia (monophobia), posttraumatic stress disorder, obsessive-compulsive disorder, panic disorder, etc.)
• Patients with a current DSM-IV-TR Axis II diagnosis that suggested non-responsiveness to pharmacotherapy or non- compliance with the protocol (e.g., antisocial or borderline personality disorder)
• Patients with a history or complication of another (non-MDD) mental disorder (schizophrenia, etc.)
• Patients with a history or complication of manic episodes
• Patients diagnosed as having an attentional deficit disorder or hyperactivity disorder
• Patients diagnosed as having a pervasive development disorder or mental retardation
• Patients diagnosed as abusing or dependent on alcohol or drug within one year before the Week -1 visit
• Patients who have undergone electroconvulsive therapy within one year before the Week -1 visit for the treatment of the current episode
• Patients who have a history of treatment with depot neuroleptics
• Patients with a history of serotonin syndrome or neuroleptic malignant syndrome
• Patients with a >= 3-point score of "suicide" (HAM-D Item 3) or patients whose Columbia Suicide Severity Rating Scale (C-SSRS) assessment suggests that they are or have been at significant risk for harming themselves or have actually harmed themselves, or who, in the opinion of the investigator (subinvestigator), are at significant risk for harming self or others.
• Patients with a history of suicide attempt, self-injurious action (excluding action with no intention of suicide) or overdo