New cancer vaccine may tackle HER2-positive tumors
New research shows that a new cancer vaccine may be effective for treating a range of HER2-positive cancers, including the more aggressive HER2-positive breast cancer.
Cancer that is human epidermal growth factor 2–positive (HER2-positive) holds too much of the protein on the surface of its cells. Excess amounts of the protein help cancer cells multiply and spread more quickly. This makes HER2-positive breast cancer more aggressive than the HER2-negative type. Bladder, pancreatic, ovarian, and stomach cancers can also be HER2-positive.
A new study suggests a possible new treatment for this cancer. Scientists, led by Dr. Jay A. Berzofsky, at the National Cancer Institute in Bethesda, MD, have come up with a cancer vaccine that demonstrated clinical benefit for people with HER2-positive cancers.
“The results of this study are very interesting and promising, especially with HER2-positive breast cancer because it’s so aggressive” said Zaw M. Bo, MD, medical oncologist and hematologist at OHC.
Dr. Berzofsky’s team used immune cells taken from the blood of 17 cancer patients, and they modified them in the laboratory. As part of the trial:
- The scientists administered the vaccine to the participants at the beginning of the study and at weeks 4, 8, 16, and 24.
- Six of the participants received the lowest dose of the vaccine (5 million dendritic cells in one shot) and 11 participants received 10 or 20 million dendritic cells.
- Participants in the lowest-dose group did not benefit from the vaccine. However, of the 11 who received a higher dose, six responded to the treatment.
- One person with ovarian cancer had a complete response to the treatment, and the benefits lasted for 89 weeks.
- One person with stomach cancer responded partially to the treatment, benefiting from the vaccine for 16 weeks.
- Four participants had stable disease as a result of the treatment. Two of these patients had colon cancer, one had prostate cancer, and another one had ovarian cancer.
- The vaccine did not cause any adverse reactions that required treatment.
Dr. Berzofsky and his team presented the findings during which they did point out some limitations to the current trial, such as the small size of the sample and the lack of a placebo group.
“Although more studies need to be done, this is another way in which scientists and doctors are looking to get the immune system to fight cancer, instead of using treatments like chemotherapy and radiation,” Dr. Bo added. “And in this study, as in most studies that evaluate immunotherapy, the patients not only responded to the treatment, but they also experienced fewer – if even any – side effects.”
Dr. Berzofsky said moving forward, the team would like to investigate whether they can increase the proportion of people who benefit from treatment with the vaccine by combining it with checkpoint inhibitor therapy. Checkpoint inhibitors block proteins that stop the immune system from attacking the cancer cells. The first ones approved by the Food and Drug Administration were tested in clinical trials at OHC in Cincinnati and include ipilimumab (Yervoy), nivolumab (Opdivo) and pembrolizumab (Keytruda).
For more information about treatment for breast cancer, call OHC at 1-800-710-4674.