[Treatment of metastatic kidney cancer with recombinant alpha-2 or gamma interferon. Results of 2 clinical phase II and III studies].

In a phase-II and a phase-III study patients with histopathologically documented metastatic renal cell carcinoma were treated either with gamma-interferon in two different doses (100 micrograms/m2 3x/week for 4 h i.v. every other week or 500 micrograms/m2 5x/week for 24 h i.v. every other week) or with alpha-2-interferon alone (18 x 10(6) U 3x/week weekly i.m.) or in combination with vinblastine (0.1 mg/kg every third week i.v.). The purpose of these studies was to evaluate the response rate, the duration of response, the survival, the efficacy and the toxicity of the different forms of treatment. The overall response rate to gamma-interferon was 30% in both regimens. The response rate of treatment with alpha-2-interferon was found to be 31%. The duration of response ranged between 2 and 34+ months in patients treated with gamma-interferon and between 2 and 24+ months in those receiving alpha-2-interferon. Patients with objective tumor response showed a significantly longer survival than those not responding (p = 0.0056). Low-dose-gamma-interferon and alpha-2-interferon treatment could be easily done on an outpatient basis. In conclusion, interferon treatment seems to be of value in the therapy of patients with well documented progressive disease in metastatic renal cell cancer.