The Role of Peptide-loaded Dendritic Cells to Augment the Therapeutic Effect of Interleukin-2

Melanoma is the main cause of death in patients with skin cancer. Once it has metastasized, this cancer has been shown to respond to chemotherapy only in rare cases. Immunotherapy represents an approach to treatment based on the immune response to cancer antigens. The principal objective of the study is to identify whether a dendritic cell-based vaccine can increase the moderate therapeutic effect of bolus high dose IL-2 in patients with metastatic melanoma. For this purpose,patients with metastatic melanoma who have a certain blood type (HLA-A201+) will be treated systemically with high dose IL-2. In one group of patients, the IL-2 will be preceded by three doses of autologous dendritic cell pulsed with melanoma antigens appropriate for their blood type. Two cycles of three DC vaccines will be administered every 14 days by intra-lymph node injections, followed by high dose IL-2 treatment. Responding patients will receive additional DC vaccines at 1 month and 2 months intervals. In a second group, patients will receive the standard high dose IL-2 protocol within a comparable period of time. Each group will include 12 patients. A complete evaluation of evaluable lesions will be performed prior to accrual, after initial 3 DC vaccines, six weeks after first IL-2 treatment, after a total of 6 DC vaccines and 6 weeks after second cycle of IL-2 treatment.