Treatment of Advanced Renal Cell Carcinoma with a Combination of Human Lymphoblastoid Interferon-Alpha and Cimetidine

Human lymphoblastoid interferon (IFN)–alpha was administered intramuscularly at doses of 5 megaunits/day 5 to 7 days a week to 32 advanced renal cell carcinoma patients. To augment the antitumor effect of IFN, cimetidine was also administered orally in doses oi 800 mg/day. This combination therapy resulted in a complete response (CR) in 6 patients (19%), a partial response (PR) in 7 (22%), a stable disease (SD) in 11 (34%), and a progressive disease (PD) in 8 (25%). The response rate (CR+PR) was 41%. The pulmonary metastases were more receptive to IFN therapy than those at other sites. The median times to response were 2 months for PR, and 4.5 months for CR. The survival of the responder patients was significantly longer than the nonresponder patients. These results suggest that IFN–alpha and cimetidine combination therapy may be of use in the management of advanced renal cell carcinoma.