IFNB1 and major depressive disorder: Furthermore, in a pooled analysis of 6 controlled studies and 17 non-controlled trials, subcutaneous IFNB-1a therapy was not linked to an increase in depression severity or suicide risk [22] and a controlled, epidemiologic study that assessed depression in 50 Italian RRMS patients and 50 healthy controls using a variety of methods (Structured Clinical Interview for Diagnostic and Statistical Manual of Mental Disorders (DSM-IV), BDI, and State Trait Anxiety Inventory) concluded that IFNB therapy was not a risk factor for depression [32].