Prospective randomized trial of natural interferon-alpha (IFN) versus IFN + cimetidine in advanced renal cell carcinoma with pulmonary metastasis

4676 Background: In the preliminary non-randomized study, combination therapy with natural IFN plus cimetidine showed high response rate in 15 out of 37 patients (41%) for advanced renal cell carcinoma. A prospective randomized multiinstitutional clinical trial to compare the effect of IFN alone to IFN + cimetidine in patients with advanced renal cell carcinoma with pulmonary metastasis was performed. Methods: Patients received IFN (5 megaunits) 5 times a week, or the IFN regimen plus daily oral cimetidine (800 mg). The primary end point was response rate, and time to progression (TTP). The secondary end point was overall survival. Results: Between April 1998 and March 2002, 71 patients from 32 institutions were randomly assigned to the two treatment groups. One patient in each group was found to be ineligible because they did not receive IFN at all. Two patients in IFN alone group stopped the treatment on day 9 and on day 10. Among 36 patients in IFN alone group, one CR, 4 PRs, 16 NCs, and 12 PDs were sh...