A New Hope for Pancreatic Cancer Patients
After a long flight left her severely dehydrated, a woman sought medical help and received a life-changing diagnosis – pancreatic cancer. Just nine days after coming back home, she underwent surgery to have the tumor removed. On the eve of starting chemotherapy, her doctors proposed an alternative: to participate in a clinical trial for a tailored mRNA vaccine. This was before the world became familiar with mRNA vaccines due to COVID-19.
The woman, now 72 and living in Florida, was the first recipient of an mRNA vaccine aimed at pancreatic cancer. Six years have passed since she took the vaccine, and her cancer has not returned. She even climbed Mount Etna in Sicily to celebrate her 50th wedding anniversary last year. She credits the mRNA vaccine for her remarkable recovery.
The Silent Killer: Pancreatic Cancer
Pancreatic cancer is one of the most lethal forms of cancer. It's often discovered late, making it an insidious enemy. Less than 13% of those diagnosed with the disease survive past five years, and it's the third most common cause of cancer-related deaths in the United States. Cases are increasing, and there's no standard screening test for early detection like there is for colon or breast cancer. Symptoms usually only show when the disease is already advanced. Only about 20% of cases are operable, and surgery is required for participation in the vaccine trial.
Current treatments like chemotherapy, radiation, and existing immunotherapies have mostly failed, underscoring the urgent need for fresh approaches. In a clinical trial's phase 1, 16 patients were included. Eight of them developed a strong immune response to the vaccine. Follow-up data after 3.2 years showed that these responders had a significantly lower recurrence rate than the ones who did not respond. Recently, extended follow-up data from the same trial covering up to six years was presented at a major cancer research conference.
Striking Results and Future Potential
The difference between the two groups is considerable. Seven of the eight responders, or 87.5%, are still alive. In contrast, only two of the eight non-responders, or 25%, are alive, with an average survival period of 3.4 years. Although this is not a new study, the ongoing immune response and survival of the patients over six years is a significant finding.
The vaccine works by eliminating cancer cells that remain in the body after surgery, preventing the disease from recurring. After the tumor is removed, it is sent for genetic analysis. A personalized vaccine is then made for each patient, based on up to 20 unique mutations in that patient's tumor. These mutations produce foreign proteins called neoantigens, which immune cells can recognize as a threat. After receiving the vaccine, patients also undergo standard chemotherapy.
The biggest challenge is that cancer cells are derived from the body itself, so the immune system doesn't naturally identify them as enemies. However, a breakthrough discovery about the rare patients who survive pancreatic cancer for years has paved the way for this vaccine. In these patients, T cells that recognized the cancer continued to circulate in the blood up to 12 years after surgery. This indicates that the immune system can remember cancer over the long term.
Next Steps and Cautious Optimism
A global phase 2 trial involving around 260 patients has already been launched to compare the vaccine's effectiveness with standard chemotherapy. At the same time, researchers are working on producing mRNA vaccines independently within their own institute. This would expand access to trials and reduce reliance on pharmaceutical companies.
Another team is developing a universal vaccine that targets the KRAS protein, common in 90% of pancreatic cancers. In a small trial, about 85% of participants developed an immune response to the protein, and a phase 2 trial is expected to start this year.
Despite the promise of this therapeutic approach, more research is needed. The phase 1 trial involved only 16 patients, and only half of them responded exceptionally well. Further studies in more advanced phases are required to examine the method in a larger population. This will help identify the patients who are best suited to this treatment. The results thus far provide optimism, but it should be tempered with caution.
As for the woman who became the first recipient of the mRNA vaccine for pancreatic cancer, she continues to live a healthy life six years after her treatment. The vaccine has truly been a miracle for her.