Interferons as antivirals in man.

Interferons have now been used in both prophylaxis and treatment of a number of human viral infections. The major action has been as a prophylactic for sites within the body that are not yet involved by disease. Such a prophylactic effect can be obtained early in the treatment of acute viral infection or even during chronic viral disease. Both local and systemic prophylaxis have been achieved with regard to both respiratory and herpesviral illness. In addition, Dane particle suppression can be achieved consistently with dosages of 10(6) units or greater daily to patients with chronic hepatitis B virus infection. In certain cases with prolonged therapy there can be permanent eradication. With leucocyte-derived material of approximately 10(6) or 10(7) units per milligram protein, the major side effects have been an initial febrile response, fatigue, malaise, marrow suppression, and inhibition of hair growth. So far, side effects have been rapidly reversible on lowering of dosage. Present studies with the use of lymphoblastoid interferon and bacterial-derived interferon employ materials of significantly greater specific activity. Such experience suggests that the same general side effects that were limiting with leucocyte interferon are present with interferon produced from recombinant DNA by bacterial as well as with lymphoblastoid interferon.