A PLACEBO-CONTROLLED, RANDOMIZED, DOUBLE-BLIND, MULTICENTER STUDY TO EVALUATE THE EFFICACY AND SAFETY OF VENLAFAXINE IN JAPANESE OUTPATIENTS WITH GENERALIZED ANXIETY DISORDER

INTERVENTION: Placebo lead‐in period (1 week): Participants will receive a placebo. Treatment period (8 weeks): Participants will receive 1 capsule of venlafaxine or placebo per day in week 1st during the treatment period and 1‐3 capsules of venlafaxine or placebo per day in 2nd to 8th week during the treatment period. Placebo Group: Participants will receive a placebo for 1st week, and 2nd week, after which they will receive a placebo for 6 weeks depending on the dose escalation criteria. Venlafaxine Group: Participants will receive venlafaxine 37.5 mg/day for 1st week, and then venlafaxine 75 mg/day for 2nd week, after 2nd week participants will receive 75 mg/day, or 150 mg/day, or 225 mg/day for 6 weeks depending on the dose escalation criteria. Tapering period (2 weeks): Participants who have completed the treatment period will taper off their study intervention. CONDITION: GENERALIZED ANXIETY DISORDER PRIMARY OUTCOME: The primary endpoint will be the change in the HAM‐A total score from baseline to treatment completion (Week 8) or discontinuation. INCLUSION CRITERIA: ‐ Participants with a diagnosis of GAD based on the DSM‐5 diagnostic criteria, which is confirmed by the Mini International Neuropsychiatric Interview (MINI). ‐ Participants with a HAM‐A total score >= 20 and CGI‐S score >= 4 both at the initiation of the screening period (Visit 1) and at baseline (Visit 3). ‐ Participants with a GAD‐7 total score >= 10 both at the initiation of the screening period (Visit 1) and at baseline (Visit 3).