IFNA1 and major depressive disorder: Moreover, it was well known that the peg-IFN and RBV treatment represents a cause for major depression in around 30% of patients [30] and many other side-effects, such as medical manifestations (fatigue and weakness) [2,4,12], or neuropsychiatric symptoms (cognitive deficit, sleep disorders, anger/hostility, anxiety) [31,32] and, in these conditions, adjunctive therapy (e.g., pharmacological, psychotherapy or psychological counseling) must be considered in order to control those side effects.