Immune Reactions and Long‐Term Therapy with Human Leukocyte Interferon

Abstract

Twenty patients with osteosarcoma were treated with exogenous human leukocyte interferon for 6-18 mo. Eleven remained free from detectable tumor growth during this treatment. Blood samples from all patients were tested for antibodies against interferon and against impurities in the interferon preparations. No patient developed detectable levels of neutralizing antibodies against interferon. All patients formed antibodies against contaminants in the concentrated crude interferon and the partially purified interferon preparation used for treatment.