Immunomodulation in the treatment of malignant disorders

In this study, 91 patients with metastatic solid tumor were treated with an immunomodulatory regimen of interferons -a and -g as well as octreide in pulse administration, followed in selected patients by low dose perilymphatic administration of interleukin-2. Pharmacosensitivity studies of patient tumor directed concomitant chemotherapy. High levels of circulating interferon-a (> 50 IU/ml) and the presence of lymphokine inhibitor factor were identified prior to treatment. None of the patients was able to produce autologous interferon. All patients had been previously treated with surgery and/or radiation therapy and/or chemotherapy. Patients had also received second line chemotherapy and/or radiotherapy per current protocols. At 30 days following immunomodulatory therapy, 6/91 patients were in complete remission; 12/91 were in partial remission; six patients progressed. At 180 days, with concomitant stem cell assay directed chemotherapy, 24/91 patients were in complete remission; 36/91 demonstrated a partial remission. Six patients progressed. Responders demonstrated a fall in circulating interferon levels as well as lymphokine inhibitor factor concomitantly with reduction in tumor burden. NK cell activity increased. Marrow studies demonstrated rises in granulocyte and thrombocyte stem cell activity. Macrophage activity also increased. The rationale for the approach is discussed.