Interferons are protein that inhibit viral replication, slow cellular proliferation, influence immune response, etc. And significant progress have been made over the past five years. Recent clinical studies have defined clinical applications for both virus and malignant disease. Interferons show limited but definite clinical effects. However, interferons will not be used as solitary agents but rather as adjuvants in conjunction with other treatment modalities. Limited supplies of interferons have prevented adequate pharmacologic studies of optimal dose, route, and schedule. Now, enough interferons will be available so that interferon therapy will be less expensive than now. All of these factors will be important in design of future clinical trials. Taking all these factors into considerations, randamized phase III investigations will be necessary to define the ultimate role of interferons in the treatment of viral and malignant
