Vortioxetine for major depressive disorder: a systematic review of the efficacy and safety profile for this newly approved antidepressant - what is the number needed to treat, number needed to harm and likelihood to be helped or harmed?

ObjectiveTo describe the efficacy and safety of vortioxetine for the treatment of major depressive disorder (MDD). Data sourcesThe pivotal registration trials were accessed by querying http://www.ncbi.nlm.nih.gov/pubmed/, http://www.clinicaltrialsregister.eu and http://www.clinicaltrials.gov for the search terms vortioxetine' and Lu AA21004', and by obtaining posters presented at congresses. Product labelling provided additional information. Study selectionAll available clinical reports of studies were identified. Data extractionDescriptions of the principal results and calculation of number needed to treat (NNT) and number needed to harm (NNH) for relevant dichotomous outcomes were extracted from the available study reports and other sources of information. Data synthesisVortioxetine is a multi-modal antidepressant that functions as a human 5-HT3A and 5-HT7 receptor antagonist, 5-HT1B receptor partial agonist, 5-HT1A receptor agonist, and inhibitor of the serotonin transporter. The recommended dose range is 5-20mg/day. Approval for the treatment of MDD was based on a clinical development programme that included six positive 6-8week studies, including one study in elderly people, and one positive maintenance study in adults. In the informative short-term studies in non-elderly patients, NNT for response with vortioxetine vs. placebo was 7 (95% CI 6-9), and NNT for remission vs. placebo was 11 (95% CI 8-17). NNH for discontinuation because of an adverse event (AE) was 36 (95% CI 24-70). The most commonly encountered AEs (incidence 5% and at least twice the rate of placebo) as identified in product labelling were nausea, constipation and vomiting, with NNH values vs. placebo of 6 (95% CI 6-7), 64 (95% CI 37-240), and 28 (95% CI 23-38), respectively. Changes in weight were not clinically relevant. ConclusionsVortioxetine represents another option for the treatment of MDD. Vortioxetine appears to have a favourable weight-gain profile. Additional information regarding the time course of response/remission and for the commonly occurring AE of nausea would be helpful to better characterise this agent. Pending clinical trials include those examining cognitive dysfunction that can accompany MDD.