A RANDOMIZED PHASE-II TRIAL OF INTERLEUKIN-2 AND INTERLEUKIN 2-INTERFERON-ALPHA IN ADVANCED RENAL-CANCER

A randomized phase II trial was performed to compare the efficacy and toxicity of interleukin 2 (IL-2) with an IL-2 and interferon alpha (IF N-alpha) regimen for the treatment of metastatic renal carcinoma. Sixt y patients with recurrent renal cell carcinoma (RCC) who had previousl y undergone a nephrectomy were randomized to receive three cycles of I L-2 or IL-2 with IFN-alpha(2b). Eighteen MU of IL-2 were administered subcutaneously on Mondays-Fridays for 3 weeks out of 4. Those patients randomized to receive the combination received the same regimen of IL -2 with 9 MU of IFN-alpha(2b) subcutaneously on Mondays, Wednesdays an d Fridays for 3 weeks out of 4. Thirty patients were randomized to rec eive each arm. Twenty-nine were evaluable in each arm. Twenty-two pati ents received three cycles of IL-2 but only 14 patients received three cycles of IL-2/IFN-alpha because of the greater toxicity of the combi nation. The principal toxicities included nausea, fatigue and fever. T here were no complete responses in either arm and only two patients wh o were treated with IL-2 attained a partial response. Twelve patients in each arm had stable disease and 15 patients in the IL-2 arm and 16 patients in the IL-2/IFN-alpha arm progressed through treatment. There were no significant differences in survival. Ten patients who receive d IL-2 are alive with a median follow-up of 266 days, whereas six pati ents who received IL-2/IFN-alpha are alive after a median of 278 days. The median survival from the time of identification of metastatic dis ease is 444 days in the IL-2 arm and 381 days in the IL-2/IFN-alpha ar m. The IL-2/IFN-alpha combination is more toxic than IL-2 alone and th is resulted in a reduced number of cycles of treatment. However, the m edian survival of the two groups was the same, suggesting that further evaluation of the IL-2/IFN-alpha combination should be confined to la rge prospective randomized clinical trials.