Background: Because of the known efficacy of several cytokines in the treatment of advanced renal cell cancer (RCC), we have conducted a phase II trial of the efficacy and toxicity of subcutaneous interferon gamma (IFNgamma) and interleukin-2 (IL-2).
Methods: 63 patients with progressive metastatic RCC were treated with 100 microg recombinant IFNgamma1b administered three times weekly during weeks 1 and 2 and with 4.5 MU recombinant IL-2 administered on 4 consecutive days during weeks 3 and 4, every 6 weeks.
Results: 11% of patients had an objective response (CR: 3%, PR: 8%), 33% had SD. Toxicity was generally mild. The median duration of remissions (CR + PR) was 9.6 months; the median duration of SD 8 months. A significant survival benefit was evident at a median observation time of 51 months for patients (44%) responding to therapy (P < 0.0001).
Conclusions: we conclude that sequential treatment with IFNgamma and IL-2 may prolong survival in patients with metastatic RCC responding to therapy.