Phase I/II study of recombinant interferon gamma in advanced renal cell carcinoma

A phase I and II evaluation of 42 patients with advanced renal cell carcinoma treated with recombinant interferon gamma was done. Patients were treated with either a daily 2-hour infusion or 24-hour infusion for 7 days every 3 weeks for at least 2 cycles. Patients who demonstrated stable disease or improvement on therapy then were continued on a maintenance program of 5 days of recombinant interferon gamma administered every 3 to 4 weeks. The initial starting dose was 10 mcg. per m.2 per day with escalations to 30, 100, 300, 1,000 and 3,000 mcg. per m.2. Dose-limiting toxicity occurred at 1,000 to 3,000 mcg. per m.2, and included leukopenia, chills, fevers, rigors and hepatotoxicity as manifested by elevation in the transaminase and bilirubin levels. Tumor responses were seen initially at the 300 mcg. per m.2 dose level. Over-all, of 41 patients evaluable for therapeutic effectiveness 1 demonstrated a complete response 6 months in duration and 3 demonstrated partial responses 2, 9 and 13 months in duration. However, 6 patients demonstrated organ site responsiveness, including resolution of pulmonary lesions (2 complete and 1 partial responses), lymphadenopathy (1 complete and 1 partial responses), a pleural-based lesion in 1 patient with a partial response and complete resolution of hepatic metastases in 1 patient. We conclude that recombinant interferon gamma at a dose of 1,000 to 3,000 mcg. per m.2 for 7 days and repeated every 2 to 3 weeks had demonstrable anticancer activity in patients with metastatic renal carcinoma.