Tolerance and effectiveness of recombinant interleukin-2 (r-met Hu IL-2 [ala-125]) and lymphokine-activated killer cells in patients with metastatic solid tumors.

The tolerance of a recombinant human interleukin-2 (rIL-2, r-met Hu IL-2 [ala-125], Ortho Pharmaceutical) and its antitumor effectiveness in combination with lymphokineactivated killer (LAK) cells was examined in 26 patients with metastatic solid tumors, including 14 renal cell carcinomas, seven melanomas, three extragonadal germ cell tumors refractory to chemotherapy and two colon carcinomas. rIL-2 was administered as a bolus at 30,000 U/kg every 8 h on days 1-5 and days 12-19. Leukapheresis was done on days 8-12, lymphocytes were incubated with rIL-2 for 3 or 4 days in vitro and reinfused on days 12, 13 and 15. The mean number of reinfused cells was 5.1 x 10(10) per patient. IL-2 dose and schedule were adjusted according to toxicity. Patients received a median of 100% (range 87-100%) of planned rIL-2 on days 1-5 and a median of 71% (range 13-100%) on days 12-19. Capillary leak syndrome with hypotension and impaired renal function and CNS toxicity were the major reasons for dose modification. Patients with renal cell carcinoma, most of whom underwent a prior nephrectomy, had a reduced tolerance to rIL-2. Partial responses were documented in three renal cell carcinomas and one melanoma. The median response duration was 5.5 (range 1-6) months.