SUBCUTANEOUS RECOMBINANT INTERLEUKIN-2 (RIL-2) IN OUT-PATIENTS WITH METASTATIC RENAL-CELL CARCINOMA - RESULTS OF A MULTICENTER SCAPP1 TRIAL

Background: This multicenter phase II trial was conducted in order to evaluate the efficacy and toxicity of the subcutaneous route of admini stration of rIL-2 in the treatment of patients with metastatic renal c ell carcinoma and to check whether an increased cumulative dose of rIL -2 increases efficacy Patients and methods: Thirty-nine patients with metastatic renal cell carcinoma were included in this study. During th e induction period, rIL-2 was administered subcutaneously 5 days a wee k for 8 weeks. The weekly dosages were 90 MIU during weeks 1 and 6; 63 MIU during weeks 2 to 4 and 7 to 9. After evaluation, responders and patients with stable disease received maintenance treatment which was discontinued upon the appearance of disease progression or unacceptabl e toxicity. During the maintenance period, rIL-2 was administered 5 da ys a week for 4 weeks followed by a 2-week rest period. The weekly dos ages were 90 MIU in week 1 and 63 MIU in weeks 2 to 4. Results: After completion of induction treatment, 7 of 39 evaluable patients (18%) ha d objective responses (95% CI: 9% to 37%) with one complete response. Treatment was interrupted or reduced due to toxicity for seven patient s: Neuropsychiatric symptoms (3 patients), joint pain (1 patient), maj or asthenia and anorexia (1 patient), stroke (1 patient), and septicem ia (1 patient). Other systemic side effects in the remaining patients were acceptable. Seventeen patients received maintenance treatment. In none of the patients did the response status improve during this main tenance period. The median follow-up of all of the patients included w as 19 months. The one- and two-year survivals were 65% and 33%, respec tively, ad the median duration of response was 11 months (5 to 16+). C onclusions: This multicentric study confirms the efficacy of subcutane ously-administered rIL-2 in patients with metastatic renal cell carcin oma in terms of both response rate and survival. The role of a mainten ance therapy needs further evaluation.