David J Hellerstein, Joseph Flaxer

It has clearly been demonstrated that depressive disorders constitute a major worldwide public health problem, with massive economic and quality-of-life consequences. Existing pharmacological treatments have limited efficacy, with only about a third of patients achieving remission on any one medication. Delayed onset of action and variable tolerability contribute to this limited efficacy. Vilazodone, introduced in the US in 2011, has been described as the first member of the serotonin partial agonist-reuptake inhibitor (SPARI) class of medications, combining serotonin-reuptake inhibition with 5-HT1A partial agonism. This agent could potentially have benefits for subgroups of depressed patients, including depressed patients with comorbid anxiety and patients with anxiety disorders, and might have fewer sexual side effects than selective serotonin-reuptake inhibitors (SSRIs). We reviewed existing clinical trials that assess the benefits of vilazodone for treatment of major depression. In clinical trials, including two Phase III studies and two Phase IV studies, vilazodone has been shown to have efficacy greater than placebo on the Montgomery-Åsberg Depression Rating Scale, comparable efficacy to citalopram, and continued benefit after 52 weeks of treatment. The safety profile for vilazodone is comparable to other SSRI medications, and tolerability also appears generally comparable to other SSRI medications. Vilazodone, which has been described as the first-of-class SPARI medication, may potentially have benefits for subgroups of patients, particularly those depressed individuals with coexisting anxiety symptoms or anxiety disorders. However, convincing evidence for these benefits has as yet not been published.