Recent research reported by Science Digest concluded that a new treatment for pancreatic cancer that combines two different approaches, virotherapy and immunotherapy, is showing great promise. Researchers studied whether treatment for pancreatic cancer would be improved by combining the Vaccinia oncolytic virus, a virus selectively modified to infect and kill cancer cells, with a gene that modifies the bodies immune system, Although lab studies showed that both killed cancer cells and provide immunity against cancer regrowth , the viruses have not performed well in clinical trials because the immune system attacks the virus before it can be effective.
After six weeks 87.5 percent of all mice treated with the combined treatment were clear of all tumors compared with 42.8 percent of those treated with Vaccinia virus alone. In addition, the survival rate of the mice almost doubled from 69.7 days to 138.5 days.
Four weeks after being clear of primary tumors, pancreatic cancer cells were reintroduced into the mice but no further doses of virus were give. Although cancer cells again grew in both groups of mice, after 32 days all except one mouse were again clear of cancer. Research is ongoing.