Interferon alfa and vinblastine versus medroxyprogesterone acetate in the treatment of metastatic renal cell carcinoma.

OBJECTIVES: Since the beginning of the 1980s, when gene technology provided sufficient amounts of cytokines, numerous Phase II studies in metastatic renal cell carcinoma were carried out mostly with interferon alfa (IFN-alpha) and interleukin-2 (IL-2). So far, no randomized prospective trials including untreated control groups have been reported. We present a prospective study comparing IFN-alpha and vinblastine (VBL) versus medroxyprogesterone acetate (MPA). METHODS: Immunochemotherapy schedule consists of IFN-alpha 8 million U/day subcutaneously for 3 days per week and VBL 0.1 mg/kg body weight intravenously at 3-week intervals. MPA was administrated intramuscularly at a dosage of 500 mg/week. The response rates, toxicities, and actuarial overall survival were analyzed. RESULTS: The overall response rate in 41 patients receiving IFN-alpha and VBL treatment was 20.5% (95% confidence interval, 9% to 33%). Four patients reached a complete and 5 patients reached a partial remission. No remissions were observed in 35 patients of the control group. A statistically significant survival benefit for the IFN-alpha and VBL group could not be demonstrated. Excluding fever, mild to moderate toxicities were observed. About one third of patients refused the proposed schedule due to general malaise and fatigue. CONCLUSIONS: A survival benefit or a favorable outcome of patients with metastatic renal cell carcinoma, treated with IFN-alpha and VBL, could not be demonstrated. As judged from this analysis, IFN-alpha and VBL therapy does not sufficiently meet the requirements of a palliative treatment of renal cell carcinoma.