A clinical trial of edrecolomab, interleukin-2 and GM-CSF in patients with advanced colorectal cancer.

Immunological effector mechanisms of monoclonal antibodies such as antibody-dependent cytotoxicity can be augmented by the cytokines granulocyte-macrophage colony-stimulating factor (GM-CSF) or interleukin-2 (IL-2). Therefore twelve patients with metastatic colorectal cancer were treated with 300 microg GM-CSF and 6 million units IL-2 subcutaneously daily from day 1 to 10 followed by a three week rest period. Of the edrecolomab 400 mg was given on day 3 of the first cycle. The dose was reduced to 150 mg on subsequent cycles. A maximum of four cycles was administered. Toxicity was manageable on an outpatient basis. No partial or complete responses were observed in these 12 patients. Median time to treatment failure was 67 days and median survival 287 days. Immunological parameters were monitored throughout the study.