Sequential administration of interferon gamma and interleukin-2 in metastatic renal cell carcinoma: results of a phase II trial

Background: Because of the known efficacy of several cytokines in the treat ment of advanced renal cell cancer (RCC), we have conducted a phase II tria l of the efficacy and toxicity of subcutaneous interferon gamma (IFN gamma) and interleukin-2 (IL-2). Methods: 63 patients with progressive metastatic RCC were treated with 100 mu g recombinant IFN gamma 1b administered three times weekly during weeks 1 and 2 and with 4.5 MU recombinant IL-2 adminis tered on 4 consecutive days during weeks 3 and 4, every 6 weeks. Results: 1 1% of patients had an objective response (CR: 3%, PR: 8%), 33% had SD. Toxi city was generally mild. The median duration of remissions (CR + PR) was 9. 6 months; the median duration of SD 8 months. A significant survival benefi t was evident at a median observation time of 51 months for patients (44%) responding to therapy (P < 0.0001). Conclusions: we conclude that sequentia l treatment with IFN gamma and IL-2 may prolong survival in patients with m etastatic RCC responding to therapy.