A phase II study of high-dose cimetidine and the combination 5-fluorouracil, interferon alpha-2A, and leucovorin in advanced renal cell adenocarcinoma.

Cimetidine is an H2-receptor antagonist used in the management of peptic ulcer disease and other hypersecretory gastrointestinal disorders. This agent has intriguing immunomodulatory characteristics. A phase II trial of cimetidine in 19 patients with advanced malignant melanoma yielded an objective response rate of 16%. Having demonstrated that cimetidine is active in malignant melanoma, the authors conducted a phase II trial of cimetidine, 800 mg twice daily by mouth, in patients with advanced renal cell cancer. Among the 31 eligible patients, only one (3.2%) achieved a regression. It was a partial regression lasting 93 days. Median time to treatment failure was 83 days. The combination of interferon alpha-2A (IFL-RA) and 5-fluorouracil (5-FU) has been shown to be synergistic against experimental cell lines in vitro. Citrovorum factor (CF) added to 5-FU has been shown to improve objective tumor response compared with single-agent 5-FU in patients with advanced colorectal cancer. Fluorinated pyrimidines have shown some activity against renal cell cancer. We conducted a phase II trial of the combination of CF at 20 mg/m2 intravenous push followed by 5-FU at 325 mg/m2 intravenously daily for 5 days every week with interferon alpha-2A 5 x 10(6) units/m2 subcutaneously on days 1, 3, 5 in patients with advanced renal cell cancer. Among the 31 eligible patients, only two (6.5%) achieved a regression. Both were partial regressions. Median time to treatment failure was 84 days. Neither regimen is recommended for further testing in patients with advanced renal cell adenocarcinoma.