Phase II trial of recombinant interferon alpha-2C in metastatic renal cell carcinoma

A total of 18 patients with advanced metastatic renal cell cancer were treated with recombinant interferon alpha-2C (rIFN alpha-2C) at daily doses of 10 X 10(6) IU by intramuscular injection. All patients had evaluable metastatic lung, liver, or abdominal disease as measured by radiographic or computerized tomographic scans. In 2 of the 18 patients an objective response (1 CR, 1 PR) with a duration of +28 and 12 months, respectively was achieved. A 25$ to 50$ decrease in tumor measurements (MR) was seen in 2 additional patients; in 3 cases a stabilisation of the disease (SD) was observed, whereas it progressed in 11. 3/4 responding patients (including MR) and all 3 cases with SD had measurable disease in the lungs as predominant site of metastatic disease. Additional clinical characteristics of patients exhibiting response or SD to IFN therapy included prior nephrectomy, favourable initial performance status and limited metastatic disease. No serious haematologic or irreversible organ toxic effects were attributed to interferon. Several patients, however, had constitutional symptoms, and major dose reductions due to CNS toxicity became necessary in two. Further studies are warranted to evaluate the use of interferons in combination with cytotoxic drugs or other biologic response modifiers.