Dendritic cell based tumor immunotherapy is a very promising approach for cancer treatment. Recent studies have shown that vaccines using the fused cells made from tumor cells and dendritic cells can stimulate tumor cell specific antitumor immune responses both in clinical studies and in pre-clinical animal studies. However, because of the difficulty of selecting and purifying the fused cells, fusion mixtures containing unfused and self-self fused cells were used in these studies. We reasoned that vaccines using purified fused cells would make the immune responses against tumors more effective. A method that purifies the fused cells (Instant Dendritomas) from the fusion mixture has been developed in our laboratory. Animal studies have shown that instant dendritomas are better activators of anti-tumor immunity than fusion mixtures. In vitro human studies using this technology have shown that instant dendritomas made from patients' own blood cells and primary tumor cells are effective in activating patients' peripheral lymphocytes to differentiate into functional cytotoxic T lymphocytes (CTLs) that efficiently lyse autologous tumor cells. Furthermore, our completed Phase I clinical trial in melanoma patients using the dendritoma vaccine demonstrated that the vaccine is safe and able to stimulate tumor cell specific immune responses. More importantly, some patients in the trial had benefited by having complete remission or stabled diseases. Based on these information, we, therefore, propose to conduct a phase II trial in patients with advanced renal cell carcinoma in order to determine if Instant Dendritoma vaccines have anti-tumor activity in a different type of cancer.
The specific aims of this study are 1) to determine if the Instant Dendritoma vaccine has anti-tumor activity (defined as complete response, partial response) in patients with stage IV renal cell carcinoma and 2) to assess if the Instant Dendritoma vaccine produces an immune response as measured by an increase in interferon production by T-cell subsets, CTL activity, and immune response in tumor used for vaccination production. Patients with advanced renal cell carcinoma who have exhausted all available therapies will be considered for this trial. The vaccine will initially be given in combination with low dose IL-2; subsequent doses of the vaccine will be given at three month intervals for up to six doses. The study will employ a two-stage approach for evaluating efficacy. Initially, 10 patients will be evaluated; if one or more patients show evidence of a clinical response, then an additional 19 patients will be enrolled in the second stage such that 29 patients are ultimately included. We anticipate it will require at least two years to complete this study. This trial has already been approved by FDA and started to enroll patients. The preliminary data from the first 5 patients enrolled in this trial are encouraging.
|Wei, Yanzhang C; Sticca, Robert P; Li, Jinhua et al. (2007) Combined treatment of dendritoma vaccine and low-dose interleukin-2 in stage IV renal cell carcinoma patients induced clinical response: A pilot study. Oncol Rep 18:665-71|