Adjunctive Vortioxetine in Schizophrenia

This is a 16-week, randomized, double-blind, parallel group, placebo-controlled study comparing adjunctive vortioxetine with identically appearing adjunctive placebo pills in 88 stable patients with a research diagnosis of schizophrenia determined with the Structured Clinical Interview for DSM (SCID). Patient randomization will be stratified by illness duration (i.e., \</=5 years and \>5 years) in order to allow for post-hoc analyses examining whether earlier illness moderates greater negative and /or cognitive symptom reduction in response to vortioxetine. Patients with clinical stability for at least 3 months and stable antipsychotic and psychotropic medication treatment for at least the last 4 weeks and without relevant depression, positive psychotic symptoms or extrapyramidal symptoms EPS will be eligible. After written informed consent, patients will undergo a screening visit to confirm full study eligibility. If all in- and exclusion criteria are fulfilled, patients will undergo a baseline assessment and then be randomized 1:1 to 16 weeks of adjunctive treatment with vortioxetine or placebo. Subsequently, patients will be seen at week 1, 2, 4 and monthly for the next 3 months.