A Pilot Study, Evaluating the Efficacy of Regulatory T-cell Suppression by Ontak in Metastatic Pancreatic Cancer

Despite improved insight into the epidemiology and biology, pancreatic cancer remains a significant health problem as evidenced by the disappointing survival rates associated with advanced disease. Because of its aggressive growth and early metastatic dissemination, only 20% of patients can be treated by surgery at the time of diagnosis. Furthermore, the overall 5-year survival rate of stage IV disease is \< 5% \[1-3\] despite chemotherapy. With such a dismal outlook, it is obvious that novel treatment strategies are required. There is limited experience in the literature with the use of Ontak in the treatment of metastatic pancreatic cancer. Viehl, et al, demonstrated in a murine model of pancreatic cancer, that ontak combined with whole tumor vaccine led to a significantly increased T cell-dependent antitumor immune response, as well as an improved survival compared to controls. Our group has an active trial at Loyola evaluating the role of dendritic cell vaccine in patients with unresectable, not metastatic, pancreatic cancer. Preliminary data suggests a correlation with time to progression and restoration of Tregs following an initial decrease after the DC injection. The goal of the current proposal is to determine the time point at which the Tregs reach the nadir within four weeks of ontak injection. When this is determined, we will eventually propose administering ontak followed by DC vaccine at the nadir Treg time point for patients with unresectable pancreatic cancer