IFNA1 and major depressive disorder: In a previous prospective study, the incidence of IFN-α-induced depression in patients who achieved remission of depressive episodes by the end of IFN-α therapy was 59.1%, whereas the other 40.9% achieved remission within 12 weeks.15 However, some studies have reported the recurrence of depression and suicidal thoughts even 6 months after the end of antiviral treatment.16 Although most IFN-α-induced depression will achieve remission after IFN-α therapy, no studies have examined the long-term mood effects of IFN-α.