Adoptive immunotherapy with tumor-infiltrating lymphocytes and subcutaneous recombinant interleukin-2 plus interferon alfa-2a for melanoma patients with nonresectable distant disease: a phase I/II pilot trial. Melanoma Istituto Scientifico Tumori Group.

Background: On the basis of our previous experience, we designed this study to determine the activity and toxicity of outpatient treatment with autologous tumor-infiltrating lymphocytes (TIL) together with intermediate-dose recombinant interleukin-2 (rIL-2) and low-dose recombinant interferon alfa-2a (rIFN-alpha2a), for patients with metastatic melanoma.

Methods: Between April 1992 and October 1994, we processed 38 melanoma samples derived from 36 patients with metastases. Proliferative cultures of expanded lymphocytes (TIL) were infused only once into patients with metastatic melanoma. rIL-2 was administered subcutaneously for 1 month, starting on the day of TIL infusion, at an escalating dose of 6-18 x 10(6) IU/m2/day for the first week and at the maximum-tolerated dose for the subsequent 3 weeks and then, after a 15-day interval, for 1 week/month for 3 months. rIFN-alpha2a was administered subcutaneously at 3 X 10(6) IU three times each week until progression.

Results: Of 38 melanoma samples, 19 (50%) resulted in proliferative cultures and were infused. The median number of expanded lymphocytes was 18 x 10(9) (range, 1-43 x 10(9)), and the median period of culture was 52 days (range, 45-60). rIL-2 was administered at doses ranging between 6 and 18 x 10(6) IU/m2/day. Toxicity was mild or moderate, and no life-threatening side effects were encountered. Two of 19 treated patients experienced complete responses of their metastatic sites (soft tissue), 10 had stable disease, and 7 showed progressive disease. The response rate was 11% (95% confidence interval, 2-35%).

Conclusions: Outpatient treatment with TIL plus rIL-2 and rIFN-alpha2a is feasible, although, within the context of the small sample size, the activity of the combination was no different from the reported activity of any of the components used alone.