First Clinical Trial for Advanced Breast Cancer Vaccine Underway at UNC (dateline July 13, 2000)

Researchers at the University of North Carolina (UNC) in Chapel Hill have begun a clinical trial to investigate whether a breast cancer “vaccine” could help treat certain patients with advanced breast cancer . The vaccine, which is not a muscle injection (shot) but an intravenous (through the vein) treatment, may be helpful to women whose cells over-produce the HER2 protein (also written as HER2/neu). 

HER2 is a protein found on cells that helps regulate cell growth.  For an unknown reason, 25% to 30% of breast cancer patients have extra copies of the HER2 protein, which could result in more aggressive tumors.  Recently, the U.S. Food and Drug Administration (FDA) has approved the drug Herceptin for use in breast cancer patients who over-produce the HER2 protein.  Now, researchers are also developing a vaccine aimed at seeking out and destroying cells carrying too much HER2. 

“The vaccine has been developed initially to test whether we can give the treatment safely to women with metastatic breast cancer and to evaluate whether the treatment boosts the immune response reactive with the tumor,” lead researcher Jonathan Serody, MD, PhD, told Imaginis.com.  “Additionally, we will watch to see if individuals in the trial will have tumor regression after the treatment.”

The vaccine is the first aimed at a specific part of the HER2 protein.  Researchers have previously attempted to engineer proteins to treat melanoma (a type of skin cancer) but not breast cancer. 

Researchers say the vaccine works by first increasing the number of dendritic cells, white blood cells that warn the immune system of potentially harmful cellular proteins.  The dendritic cells take fragments of the HER2 protein and rush back to the lymph nodes to alert the killer T-cells of the immune system.  The killer T-cells then launch an attack on the cells with an overabundance of the HER2 protein. 

A breast cancer patient from Rochester, New York received the first vaccine infusion on July 6.  The UNC researchers are still enrolling patients for the clinical trial.  Dr. Serody anticipates that enrollment will continue for the next 18 months.  Women interested in participating in the trial must meet the following requirements: 

• Patients must have Stage IV (metastatic) breast cancer. 
• Patients must have disease stability for one month.
• Patients must be off of chemotherapy (although previous treatment with chemotherapy is acceptable).

In the trial, which is supported by the Breast Cancer Research Foundation, patients will be randomly assigned to receive either dendritic cells with the engineered HER2 fragment or a fragment of a non-engineered (normal) protein.  The treatment involves three 30-minute infusions three weeks apart. 

Dr. Serody and his colleagues hope the trial will determine whether the vaccine can help shrink tumors in women with advanced (Stage IV) breast cancer.  Currently, the five-year survival rate for Stage IV breast cancer is approximately 16%.  If the current trial and future trials prove successful, the vaccine could eventually be used earlier as an alternative treatment for women at risk of metastatic breast cancer (for example, before chemotherapy is given). 

Additional Resources and References

• The June 29, 2000 University of North Carolina-Chapel Hill news report by Leslie H. Lang, “UNC-CH Opens First Trial of Vaccine Treatment for Advanced Breast Cancer,” is available at http://www.unc.edu/news/newsserv/research/breast062900.asp
• To learn more about the HER2 protein or the drug Herceptin, please visit http://www.imaginis.com/breasthealth/herceptin.asp
• To learn more about advanced breast cancer, please visit http://www.imaginis.com/breasthealth/metastatic.asp