Phase II trial of lymphoblastoid interferon in metastatic colon carcinoma.

Nineteen patients with advanced metastatic colon carcinoma were treated with human lymphoblastoid interferon at a dose of 3.0 X 10(6) units/m2 im three times/week for 6 weeks. Patients who did not progress at the 6-week interval were randomized to receive maintenance treatment with either interferon (3.0 X 10(6) units/m2 once/week) or no further treatment. All patients had evaluable metastatic lung, liver, or abdominal disease as measured by radiographs or computerized tomographic scans. Complete remission or partial remission of greater than 50% decrease in tumor measurements was not demonstrated with interferon treatment. Among 18 evaluable patients, seven had stabilization of measurable disease at 6 weeks, but 11 showed progressive disease. Of the seven patients followed during maintenance, only one (placebo maintenance) remained with no objective progression. No serious organ toxic effects were attributed to interferon, but one patient demonstrated liver enzyme elevation that persisted after cessation of interferon therapy. All patients had significant constitutional symptoms of fever, muscle aches, and malaise. Using interferon at the dose schedule outlined, this study failed to demonstrate significant regressions in metastatic colon carcinoma.