A safety and efficacy trial of lethally irradiated allogeneic pancreatic tumor cells transfected with the GM-CSF gene in combination with adjuvant chemoradiotherapy for the treatment of adenocarcinoma of the pancreas

Abstract

3010 Background: Pancreatic cancer remains the fourth leading cause of cancer related deaths in the US in 2006. Surgical resection provides the only possibility of cure. A standard adjuvant treatment approach for patients with resected disease has not yet been determined. We have developed an irradiated GM-CSF transfected allogeneic whole cell line pancreas adenocarcinoma vaccine. We have previously reported a follow-up 60 patient study in this same population using the highest bioactive vaccine dose identified in the initial phase I study. Methods: Single institution phase II study of 60 patients with resected pancreatic adenocarcinoma administered a total of 5 vaccines using two pancreatic cancer cell lines each delivering 2.5 X 10 8 cells ID. Vaccine one was administered 8–10 weeks following surgical resection. Patients subsequently were treated with 5-FU CI based chemotherapy integrated with radiotherapy. Patients who were disease-free one month after completion of chemoradiotherapy received vaccines 2–4, each 1 month apart. A fifth and final booster vaccine was administered 6 months after vaccine 4. The objectives of the study were: 1. To estimate overall survival and disease-free survival in patients with minimal residual disease treated with adjuvant chemoradiotherapy in sequence with the irradiated allogeneic GM-CSF transfected pancreatic tumor cell lines. 2. To characterize toxicities associated with intradermal injections of the vaccine. Results/Conclusions: The study completed enrollment of new patients in January 2005. Median follow-up for these patients is approximately 36 months. 1) The administration of a GM-CSF allogeneic pancreas cancer vaccine is safe and well tolerated; 2) The median survival is approximately 26 months. These results compare favorably with published data for resected pancreas cancer; 3) A matched cohort analysis comparing patients enrolled on this adjuvant vaccine study to the Johns Hopkins Surgery database of patients receiving surgery followed by chemoradiotherapy alone will be presented at this meeting; 4) Immune correlates will be presented at this meeting. No significant financial relationships to disclose.