Allogeneic gene-modified tumour cells in metastatic kidney cancer. Preliminary report

An allogeneic irradiated RCC cell line, engi- neered to produce IL-2 (ACHN-IL-2), admixed with autologous metastatic formalin-treated tumour cells, was used to vaccinate ten MRCC patients in progres- sion of disease in spite of IL-2 immunotherapy. The cells were administered subcutaneously and/or intra- tumourally. Sixty-four MRCC patients in progressive disease, not treated by vaccination but receiving simi- lar IL-2 immunotherapy, were considered as the con- trol group. Patients received 4n16 injections (mean 9 ± 4), contain- ing an average of 10.6 x 10 7 ± 7.7 x 10 7 ACHN-IL-2- transfected cells (a minimum of 4 x 10 7 , and a maximum of 31 x 10 7 ). Four patients also received intra-tumour injections. Vaccination was administered during 30n418 days, and the follow-up continued for 649 ± 353 days (190n1342). Throughout this period, the patients continued receiving the previously set immunotherapy treatment. No adverse side effects related to the treatment were observed. One complete and one partial tumour response were observed, as well as two stable and one no-relapse disease. All but one patient died. Responding patients resumed progression in 4n11 months and died 18 and 36 months after beginning the vaccine therapy. In spite of the small number of treated patients, Wilcoxonis test showed a significant (P < 0.05) improve- ment of the survival in the vaccinated group compared to that of the control. The described vaccination proto- col seems safe, devoid of adverse side effects and promis- ing. It warrants further investigation.