Vaccine Treatment for Surgically Resected Pancreatic Cancer

This 2-phase study will determine the safety of treating patients with pancreatic cancer with the genetically engineered HyperAcute-Pancreatic cancer vaccine. It will establish the proper vaccine dose and will examine side effects and potential benefits of the treatment. The vaccine contains killed pancreatic cancer cells containing a mouse gene that causes the production of a foreign pattern of protein-sugars on the cell surface. It is hoped that the immune response to the foreign substance will stimulate the immune system to attack the patient's own cancer cells that have similar proteins without this sugar pattern, causing the tumor to remain stable or shrink. Patients 18 years of age or older with pancreatic cancer that has been surgically resected may be eligible for this study. Candidates will be screened with medical history and physical examination, blood tests, urinalysis, chest x-rays and CT scans. MRI, PET, and ultrasound scans may be obtained if needed. Participants will receive twelve vaccinations two weeks apart from each other. The vaccines will be injected under the skin, similar to the way a tuberculosis skin test is given. Phase I of the study will treat successive groups of patients with increasing numbers of the vaccine cells to evaluate side effects of the treatment and determine the optimum dose. Phase II will look for any beneficial effects of the vaccine given at the highest dose found to be safe in Phase I. Monthly blood samples will be drawn during the 6 months of vaccine treatment. In addition, patient follow-up visits will be scheduled every 2 months for the remaining first year (6 months) after vaccination and then every 3 months for the next 2 years for the following tests and procedures to evaluate treatment response and side effects: Medical history and physical examination Blood tests X-rays and various scans (nuclear medicine/CT/MRI) FACT-Hep Assessment questionnaire to measure the impact of treatment on the patient's general well-being. The questionnaire is administered before beginning treatment, monthly during treatment, and during follow-up visits after completing the treatment. It includes questions on the severity of pancreatic cancer symptoms and the ability to perform normal activities of daily life.

According to statistics of the American Cancer Society, an estimated 31,000 individuals will be diagnosed with pancreatic cancer and 25,000 will die of the disease, making it the fifth leading cause of U.S. cancer deaths this year despite all current therapy. This protocol attempts to exploit an approach to pancreatic cancer immunotherapy using a naturally occurring barrier to xenotransplantation in humans in an attempt to vaccinate patients against their pancreatic cancer. The expression of the murine alpha (1,3) galactosyltransferase \[alpha (1,3) GT\] gene results in the cell surface expression of alpha (1,3) galactosyl-epitopes (alpha-gal) on membrane glycoproteins and glycolipids. These epitopes are the major target of the hyperacute rejection response that occurs when organs are transplanted from non-primate donor species into man. Human hosts often have pre-existing anti-alpha-gal antibodies that bind alpha-gal epitopes and lead to rapid activation of complement and cell lysis. The pre-existing anti-alpha-gal antibodies found in most individuals are thought to be due to exposure to alpha-gal epitopes that are naturally expressed on normal gut flora leading to chronic immunological stimulation. These antibodies may comprise up to 1% of serum IgG. In this Phase I/II trial, patients with surgically resected pancreatic cancer will undergo a series of twelve intradermal injections with a vaccine composed of irradiated allogeneic pancreatic cancer cell lines (HAPa-1 and HAPa-2) that have been transduced with a recombinant Moloney murine leukemia virus (MoMLV)-based retroviral vector expressing the murine alpha (1,3) GT gene. Endpoints of the study include determination of dose-limiting toxicity (DLT), maximum tolerated dose (MTD), tumor and immunological responses.