A randomized controlled pilot trial of vilazodone for adult separation anxiety disorder

Separation anxiety disorder was recently recognized by fifth edition of the Diagnostic and Statistical Manual of Mental Disorders as a diagnosis in adults, but no publications to date have characterized a sample of patients seeking treatment for adult separation anxiety disorder (ASAD) or assessed treatment efficacy. We hypothesized that vilazodone, a selective serotonin reuptake inhibitor (SSRI) and serotonin 1a (5HT1_a ) receptor partial agonist, would have efficacy in ASAD, because SSRIs have appeared efficacious in children with mixed diagnoses including separation anxiety disorder and in animal models of separation anxiety.

In this pilot study, 24 adults (ages 18-60) with a principal diagnosis of ASAD were randomized to 12 weeks of double-blind treatment with vilazodone (n = 13) or placebo (n = 11). Outcome was assessed by an independent evaluator and self-ratings, and analyzed with mixed effect models.

This sample was predominantly female (67%), with comorbid psychiatric disorders (58%), and adult onset of separation anxiety disorder (62%). Response rates at week 12 did not differ significantly between groups. Across all time points, the vilazodone group evidenced greater improvement on the Structured Clinical Interview for Separation Anxiety Symptoms (P = .026) and the Quality of Life Enjoyment and Satisfaction Questionnaire (P = .011), and trends toward greater improvement on the Adult Separation Anxiety Questionnaire (P = .054) and the Clinical Global Impression-Change Scale (P = .086), all with large between-group effect sizes.

Findings demonstrate feasibility of a clinical trial in ASAD, and they suggest that vilazodone may have efficacy in the treatment of ASAD and warrants further study.