Vilazodone

Vilazodone is a novel compound with combined high affinity and selectivity for the 5-hydroxytryptamine (5-HT) transporter and 5-HT(1A) receptors. It has been shown to be equally efficacious as other antidepressants with similar gastrointestinal side effects and possibly with reduced sexual side effects and weight gain. Vilazodone is an antidepressant agent that can used as an alternative for patients who cannot tolerate therapy with other antidepressant classes such as selective serotonin reuptake inhibitors or serotonin norepinephrine reuptake inhibitors. (In Vitro):Vilazodone shows an IC50 of 0.2 nM at the human 5-HT1A receptor and 0.5 nM for the SERT. Vilazodone preferentially binds to the high agonist affinity state of human 5-HT1A receptors, and it displays high affinity (pKi≥9.3) for human recombinant and rat, guinea pig, mouse, and marmoset native tissue 5-HT1A receptors.Vilazodone acts as a high efficacy partial agonist at 5-HT1A receptors. In [35S]GTPγS binding studies in Sf9 cells expressing h5-HT1A receptors, a single concentration of Vilazodone (100nM) increases basal binding by approximately 70% of that produced by the full 5-HT1A receptor agonist, 8‐OH‐PIPAT.In [35S]GTPγS binding studies in rat hippocampal membranes, Vilazodone acts as a potent 5‐HT1A receptor partial agonist with a pEC50 of 8.1 and an intrinsic activity of 0.61.Vilazodone acts as a potent 5‐HT reuptake inhibitor in rat and guinea pig cortex. In LLCPK cells expressing human SERT, whereby vilazodone inhibits [3H]5‐HT uptake with a pIC50 of 8.8.(In Vivo):Vilazodone (intraperitoneal injection; 3 mg/kg ; single dose) produces increases in extracellular levels of 5‐HT in both the frontal cortex (FC) and ventral hippocampus (vHipp) of rats in vivo microdialysis studies. Maximum increases are observed at 3 mg/kg and reaches 527% and 558% of preinjection baseline values in the FC and vHipp, respectively.Vilazodone (oral gavage ;55 mg/kg ; single dose) inhibits stress‐induced vocalizations in the rat ultrasonic vocalizations test at 120 and 210 min post dose.