Cancer vaccine possible?
How would a cancer vaccine work, and how close are we to getting one?
Q: How would a cancer vaccine work, and how close are we to getting one? — Phyllis J., San Diego
A: Much of the work that’s going on with cancer vaccines now involves personalized medicine. Scientists tailor each vaccine to YOUR immune system and train it to kill cell mutations (that’s the cancer) that are unique to YOU.
In the U.S., a small clinical trial of what’s called a neoantigen vaccine focused on folks with melanoma. It targeted 20 predicted personal tumor neoantigens in the participants; neoantigens are a peptide — two or more amino acids — that arise from tumors. Four of six vaccinated patients had no recurrence of the disease 25 months after vaccination. Two who had recurrence were then treated with anti-PD-1 (anti-programmed cell death-1) therapy and had complete tumor regression.
Another study, in Germany, used what are called personalized RNA mutanome vaccines to effectively mobilize immunity against cancer mutations in melanoma. The approach used in the German vaccine trial was to do very thorough genetic sequencing of a person’s tumor and compare that to a genetic sequencing of healthy cells in that person. The researchers then identified parts of the “healthy” genome that they thought would activate immune system T cells to efficiently kill tumor cells. From that information, they made a vaccine and injected it into the person’s lymph nodes.
The results? The German study included 13 people with melanoma; all had experienced multiple relapses of the disease, but eight of the 13 were tumor-free when they got the personalized vaccine. Over the 23-month follow-up, all eight remained tumorfree. The other five patients had relapses before they received the personalized vaccines, but one of them saw measurable tumor shrinkage and another became tumor-free after receiving the vaccination.
Many other approaches are being considered, as well, and you can bet cancer vaccines will become a powerfully precise way to beat cancer in the future. Some researchers are even testing vaccines that prevent the disease! Stay tuned.
Dr. Mehmet Oz is host of “The Dr. Oz Show,” and Dr. Mike Roizen is Chief Wellness Officer and Chair of Wellness Institute at Cleveland Clinic. Email your health and wellness questions to Dr. Oz and Dr. Roizen at youdocsdaily@ sharecare.com.