Actavis plc, a unique specialty pharmaceutical company, has received the US Food and Drug Administration (FDA) approval for a lower therapeutic dose of Viibryd (vilazodone HCl) (20mg) to accompany the 40 mg daily therapeutic dose. This supplemental new drug application (sNDA) approval for Viibryd expands dosing options available to health care providers when using Viibryd to treat their adult patients with MDD. The Viibryd 20mg therapeutic dose is now available in pharmacies.

Viibryd was approved in January 2011 as the first and only selective serotonin reuptake inhibitor (SSRI) and 5HT1a receptor partial agonist for the treatment of MDD in adults at a dose of 40 mg/day. The approval of the 20 mg dose fulfills a post-marketing commitment with the FDA to identify the minimum effective dose of vilazodone.

Approval of the 20 mg dose was supported by a 10-week, multicenter, double-blind, placebo-controlled and active-comparator, parallel-group, fixed-dose trial of 1133 adult patients with MDD. The primary efficacy outcome was the mean change in Montgomery-Asberg Depression Rating Scale (MADRS) total score from baseline to week 10. Significantly greater reduction in mean MADRS total scores from baseline to week 10 was found in both vilazodone treatment groups (Least square mean difference (LSMD): vilazodone 20, 40 mg/day: -2.6, -2.8 respectively) compared with placebo. A secondary outcome was the change from baseline to week 10 on the Clinical Global Impressions-Severity scale (CGI-S), which is a measure of illness severity that is commonly used in MDD clinical trials. Both vilazodone dose groups significantly reduced illness severity compared with placebo as measured by the change from baseline in CGI-S score. For both the MADRS total score and CGI-S score, significant differences in favor of the vilazodone groups were observed as early as week 2 and were maintained through week 10. Whether the statistically significant differences observed at time points earlier than 10 weeks in MADRS total score and CGI-S score represent clinically relevant treatment effects in this study are unknown. Adverse events that occurred in at least 5% of patients in either vilazodone dose group and at twice the rate of placebo were diarrhea, nausea, insomnia, and vomiting. These results support the efficacy, safety, and tolerability of Viibryd 20 mg once daily as a therapeutic dose in the treatment of MDD in adults.

Viibryd has been shown to be effective in the treatment of MDD in adults across 4 clinical studies. Viibryd should be taken with food and initiated at a dose of 10 mg once daily for 7 days, followed by 20 mg once daily. Based on efficacy and tolerability, the dose may be increased to 40 mg daily after a minimum of 7 days between dosage increases.

Vilazodone, also known by its brand name Viibryd, is a selective serotonin reuptake inhibitor (SSRI) and 5-HT1A receptor partial agonist approved by the FDA for the treatment of adults with Major Depressive Disorder (MDD). While the mechanism of the antidepressant effect of vilazodone is not fully understood, it is thought to be related to enhancement of serotonergic activity through selective inhibition of serotonin reuptake. The role of 5HT1A partial agonist activity on serotonergic transmission and antidepressant effect is unknown.