Combined levamisole with recombinant interleukin-2 (IL-2) in patients with advanced renal cell carcinoma: A phase II study

Adoptive immunotherapy (AI) with interleukin-2 (IL-2) and lymphokine-activated killer (LAK) cells is an antineoplastic modality in which immune-activated cells are administered to a host having cancer in an attempt to mediate tumor regression. Levamisole (LEV), an immune stimulant, has been suggested as having therapeutic effectiveness in a variety of cancers. After a phase I trial of recombinant IL-2 plus LEV, a phase II trial of this combination was conducted in patients who had advanced renal cell carcinoma. The regimen was IL-2 at 3 x 10(6) U/m2 daily x 5 plus LEV at 50 mg/m2 perorally three times a day x 5. Only one of the 22 eligible patients had a regression. It was a partial regression, 85 days in duration. The median time to treatment failure (refusal, progression, or off study because of toxicity) was 36 days. The only grade 4 toxicity reported was lethargy. This regimen is not recommended for further testing in patients who have advanced renal cell carcinoma.