Pancreatic Cancer Vaccine Shows Potential in Early Trial
The five-year survival rate of people diagnosed with pancreatic cancer is currently 13 percent.
The American Cancer Society estimates that about 67,440 Americans (34,950 men and 32,490 women) will be diagnosed with pancreatic cancer this year. Of those, about 51,980 people (27,050 men and 24,930 women) will die of pancreatic cancer. The lifetime risk of pancreatic cancer is about 1 in 56 in men and about 1 in 60 in women.
Pancreatic cancer is one of the more deadly forms of this malady because around 80 percent of patients will be diagnosed at Stage IV, which is after the cancer has metastasized throughout the body. Stage IV pancreatic cancer has a five-year survival rate of 1 percent. Overall, the five-year survival rate of people diagnosed with pancreatic cancer is 13 percent. If the disease is caught very early, up to 10 percent of patients become disease-free.
Compare those grim statistics with the overall five-year survival rates for breast and prostate cancers (91 percent and 97 percent, respectively).
Two breakthroughs are bringing hope for successfully treating this malignancy. First, researchers at the Oregon Health & Science University reported earlier this month in Science Translational Medicine that they had developed a simple blood test that can detect the activity of proteins associated with early-stage pancreatic cancer. Nature notes that the test "correctly identified healthy individuals 98% of the time, and identified people with pancreatic cancer with 73% accuracy. It always distinguished between individuals with cancer and those with other pancreatic diseases." Combining the new test with another standard test improves diagnostic accuracy to 85 percent. The researchers calculate that the test would take 45 minutes to run at a cost of only 1 cent per test. Regularly deploying this test means that the cancer could be detected and treated much earlier. The five-year survival rate for Stage I pancreatic cancer is around 83 percent.
In other good news, researchers associated with the Memorial Sloan Kettering (MSK) Cancer Center recently reported preliminary success in using therapeutic cancer vaccines for treating pancreatic cancer. The researchers designed personalized vaccines by genetically sequencing tumors that had been surgically removed from patients, looking for specific mutations that produced proteins associated with their cancer. Based on mRNA technology (similar to that used to successfully develop several COVID-19 vaccines), the bespoke vaccines instruct patients' cells to make cancer proteins that are most likely to trigger an immune response.
The researchers administered the vaccines to 16 patients in their phase 1 clinical trial. Of the eight patients whose immune systems responded to the vaccine, six have not seen their cancers return in the over 3-year follow-up period. The other two patients with weaker immune responses relapsed. While promising, it is important to keep in mind that half of the 16 patients did not respond to the vaccine, and their cancers recurred in seven of the eight non-responders at a median of 13.4 months after surgery.
The researchers are now engaged in a phase 2 clinical trial involving 260 patients, half of whom will be infused with the anti-cancer vaccine while the other half will receive the standard care of surgery and chemotherapy for their tumors. The goal is to see if the survival rates for patients treated with the vaccine are significantly better than for those receiving standard care.
In an MSK press release, Vinod Balachandran, a surgical oncologist and principal investigator of the trial, suggested, "If you can do this in pancreas cancer, theoretically you may be able to develop therapeutic vaccines for other cancer types."
