High-dose, continuous infusion Interleukin-2 in the treatment of metastatic renal cell carcinoma: Experience of the C.R.O., Aviano

Interleukin-2 (IL-2, Proleukin, Chiron Therapeutics Inc., Emeryville, CA) has been approved in Italy for the therapy of patients affected by metastatic renal cell carcinoma (RCC) with a good performance status. The basis for approval in the USA and Europe was a series of clinical trials demonstrating that high-dose IL-2, although significantly toxic, can obtain approximately 20% objective responses and improve survival. Between July 1988 and September 1993, 50 patients were treated with high-dose IL-2 in continuous infusion (according to the West protocol), first as part of a European multicentric study, and subsequently as standard treatment. Responses were seen in 9 of the 45 evaluable patients, and, at the last control (December 1995), an improvement in the survival of responding or unchanged patients was clear. This statement may seem excessive but is based on clinical evidence showing a change in the natural history of some of our patients, which is unusual in patients with solid tumors, and in particular RCC patients.