Efficacy and Safety of Extended-Release Venlafaxine in the Treatment of Generalized Anxiety Disorder in Children and Adolescents: Two Placebo-Controlled Trials

OBJECTIVE: The authors evaluated the efficacy, safety, and tolerability of extended-release venlafaxine in the treatment of pediatric generalized anxiety disorder. METHOD: Two randomized, double-blind, placebo-controlled trials were conducted at 59 sites in 2000 and 2001. Participants 6 to 17 years of age who met DSM-IV criteria for generalized anxiety disorder received a flexible dosage of extended-release venlafaxine (N=157) or placebo (N=163) for 8 weeks. The primary outcome measure was the composite score for nine delineated items from the generalized anxiety disorder section of a modified version of the Schedule for Affective Disorders and Schizophrenia for School-Age Children, and the primary efficacy variable was the baseline-to-endpoint change in this composite score. Secondary outcome measures were overall score on the nine delineated items, Pediatric Anxiety Rating Scale, Hamilton Anxiety Rating Scale, Screen for Child Anxiety Related Emotional Disorders, and the severity of illness and improvement scores from the Clinical Global Impression scale (CGI). RESULTS: The extended-release venlafaxine group showed statistically significant improvements in the primary and secondary outcome measures in study 1 and significant improvements in some secondary outcome measures but not the primary outcome measure in study 2. In a pooled analysis, the extended-release venlafaxine group showed a significantly greater mean decrease in the primary outcome measure compared with the placebo group (-17.4 versus -12.7). The response rate as indicated by a CGI improvement score <3 was significantly greater with extended-release venlafaxine than placebo (69% versus 48%). Common adverse events were asthenia, anorexia, pain, and somnolence. Statistically significant changes in height, weight, blood pressure, pulse, and cholesterol levels were observed in the extended-release venlafaxine group. CONCLUSIONS: Extended-release venlafaxine may be an effective, well-tolerated short-term treatment for pediatric generalized anxiety disorder.