Personalized mRNA Vaccine Shows Early Promise for Pancreatic Cancer
While pancreatic cancer accounts for only 3% of all cancers in the U.S., it causes 7% of all cancer deaths. Because it does not cause symptoms in the early stages, pancreatic cancer is usually not detected until it has progressed to a later stage, making it more difficult to effectively treat.
By the time pancreatic cancer is detected, it has often grown to a considerable size, entangled in nearby vessels and tissues, and sometimes has spread to nearby organs such as the liver, abdominal lining and lungs.
“Pancreatic cancer is often difficult to surgically remove, but the cells are notoriously evasive and resilient, too,” said Dr. Jason Fleming, chair of the Gastrointestinal Oncology Program at Moffitt Cancer Center. “This makes the cancer resistant to many other standard therapies, like chemotherapy and radiation.”
But a new study led by Dr. Vinod Balachandran at Memorial Sloan Kettering Cancer Center has shown promising results using a form of immunotherapy to combat the tough-to-treat cancer.
The phase 1 study, recently published in the journal Nature, used a personalized messenger RNA vaccine to target pancreatic cancer in 16 participants.
“With these personalized vaccines, an individual’s unique changes in DNA were sequenced and an mRNA vaccine was produced specific to their cancer,” said Dr. Patrick Hwu, Moffitt president and CEO and renowned tumor immunologist. “The goal of the vaccine was to stimulate the activation of T cells that would directly target and kill their cancer cells.”
Eight of the study participants responded to the vaccine and have had no recurrence of their cancer.
“Though this is a small study, the results are very exciting. Pancreatic cancers have mutations that make them difficult to target through traditional therapies,” Hwu said, “but this shows that the mutations may be good antigens to target through the immune system.”
Additionally, the study notes that of the eight participants who did not respond to the vaccine and produce an effective immune response, seven had their spleens removed as part of their pancreatic cancer surgery. “The spleen is a major immune organ and can be important to help with the efficacy of vaccines like this,” Hwu said.
Hwu says it is also important to note that study participants mounted equivalent responses to an unrelated mRNA vaccine, the COVID-19 vaccine. “This control shows that the differing responses are not just based on the health of each patient’s immune system.”
Intercepting Pancreatic Cancer
Unlike with colon and breast cancers, there are no population-based screening guidelines for pancreatic cancer. For individuals at higher risk for the disease, such as those with family history, pancreatic cysts and other risk factors, Moffitt is launching a first-of-its-kind clinic focused on risk stratification, patient education, surveillance, and engagement in clinical trials and studies devoted toward mitigating the risk. The clinic is slated to open this year. Learn more here.
