Venlafaxine extended release vs placebo and paroxetine in social anxiety disorder.
BACKGROUND
Evidence indicates that venlafaxine hydrochloride extended release (ER) effectively ameliorates anxiety symptoms.


OBJECTIVE
To evaluate the efficacy, safety, and tolerability of flexible-dose venlafaxine ER compared with placebo in the short-term treatment of generalized social anxiety disorder and, secondarily, to compare paroxetine with venlafaxine ER and paroxetine with placebo.


METHODS
Adult outpatients with DSM-IV generalized social anxiety disorder for 6 months or longer were randomly assigned to receive venlafaxine hydrochloride ER (75-225 mg/d), paroxetine (20-50 mg/d), or placebo for 12 weeks or less at 26 centers in the United States. The primary outcome measure was the total Liebowitz Social Anxiety Scale score. Secondary measures included response (Clinical Global Impression-Improvement score, 1 or 2) rates and Clinical Global Impression-Severity of Illness and Social Phobia Inventory scores.


RESULTS
Of 440 patients treated, 413 (93.9%) were included in the last-observation-carried-forward efficacy analysis; of the 429 patients in the safety population, 318 (74.1%) completed the study. Mean daily doses were 201.7 mg (SD, 38.1 mg) of venlafaxine hydrochloride ER and 46.0 mg (SD, 7.9 mg) of paroxetine. Venlafaxine ER treatment was significantly superior to placebo at weeks 1 through 12 on the Liebowitz Social Anxiety Scale and Social Phobia Inventory and at week 2 and weeks 6 through 12 for Clinical Global Impression-Severity of Illness and responder status, and was significantly superior to paroxetine treatment at weeks 1 and 2 for the Social Phobia Inventory (P < .05 for all). Paroxetine treatment was significantly superior to placebo at weeks 3 through 12 on the Liebowitz Social Anxiety Scale, the Clinical Global Impression-Severity of Illness scale, and the Social Phobia Inventory, and at weeks 4 through 12 for response (P < .05 for all). Week 12 response rates were significantly greater for the venlafaxine ER and paroxetine groups (58.6% and 62.5%, respectively) vs the placebo group (36.1%) (P < .001 for both).


CONCLUSIONS
Venlafaxine ER is effective in the short-term treatment of generalized social anxiety disorder, with efficacy and tolerability comparable to paroxetine.
Liebowitz
Michael R
MR
New York State Psychiatric Institute, New York 10032, USA. mrl1945@aol.com
Gelenberg
Alan J
AJ
Munjack
Dennis
D
D000328:Adult; D003511:Cyclohexanols / Q000009:adverse effects / Q000627:therapeutic use*; D003692:Delayed-Action Preparations; D004311:Double-Blind Method; D004334:Drug Administration Schedule; D005260:Female; D006801:Humans; D008297:Male; D009325:Nausea / Q000139:chemically induced; D017374:Paroxetine / Q000009:adverse effects / Q000627:therapeutic use*; D010698:Phobic Disorders / Q000175:diagnosis / Q000188:drug therapy* / Q000523:psychology; D010919:Placebos; D011569:Psychiatric Status Rating Scales; D017367:Selective Serotonin Reuptake Inhibitors / Q000009:adverse effects / Q000627:therapeutic use*; D007319:Sleep Initiation and Maintenance Disorders / Q000139:chemically induced; D016896:Treatment Outcome; D000069470:Venlafaxine Hydrochloride
D003511:Cyclohexanols; D003692:Delayed-Action Preparations; D017374:Paroxetine; D010919:Placebos; D017367:Selective Serotonin Reuptake Inhibitors; D000069470:Venlafaxine Hydrochloride