PHASE-II TRIAL OF LOW-DOSE GAMMA-INTERFERON IN METASTATIC RENAL-CELL CARCINOMA

We conducted a phase II trial to confirm the activity of fixed, low do se gamma-interferon in metastatic renal cell carcinoma. A total of 35 patients with metastatic renal cell carcinoma, who had not received pr ior immunotherapy and who had a Zubrod performance status of 2 or less , was enrolled in this study. Primary tumors were controlled by nephre ctomy or embolization before treatment began. gamma-Interferon was adm inistered weekly as a subcutaneous injection at a fixed dose of 100 mu g. Toxic effects were limited to low grade fever, chills and myalgias within 24 hours of injection. There were no incidences of grade 3 or 4 toxicity. Responses could be evaluated in 34 patients. There were 1 complete and 4 partial responses, for an objective response rate of 15 % (95% confidence interval 5 to 32%). Durations of response to date ar e 21+, 17+, 13+, 9 and 2 months. We conclude that gamma-interferon is an active agent for metastatic renal cell carcinoma when administered according to this dose and schedule. The response rate compares favora bly with those of alpha-interferon and interleukin-2, and toxicity is minimal. gamma-Interferon has excellent potential for use in combinati on with other biological or chemotherapeutic agents and in the adjuvan t setting.