CHICAGO A breast cancer vaccine already shown to elicit a powerful immune response in women with varying levels of HER2 expression has the ability to improve recurrence rates and is well tolerated in an adjuvant setting, according to new research from a clinical trial led by researchers at The University of Texas MD Anderson Cancer Center.
The findings, released today, will be presented on Monday, June 4 in an oral presentation at the 2012 Annual Meeting of the American Society of Clinical Oncology (ASCO). It builds on previous research showing the vaccine, known as AE37, to safely and effectively raise immunity against human epidermal growth factor receptor 2 (HER2) an oncoprotein that promotes tumor growth and is expressed to some extent in 75-80% of breast cancer tumors.
The researchers found that patients who received the vaccination had an estimated recurrence rate of 10.3% compared to 18% in the control group at a median follow up of 22 months. This represented a 43% reduction in the risk of recurrence.
"The vaccine educates the immune system to recognize HER2 as an invader," said Elizabeth Mittendorf, M.D., assistant professor in the Department of Surgical Oncology at MD Anderson and the trial's national principal investigator. "By introducing it into women who have had breast cancer, our goal is to instruct the immune system to immediately recognize any recurring cancer cells and orchestrate an attack."
Building a Powerful Vaccine
The AE37 peptide vaccine used in this study is a hybrid modified to increase its potency in generating an immune response specific to cancer cells expressing HER2. It consists of a fragment of the HER2 protein (AE36), a MHC Class II epitope, linked to an Ii-Key peptide. Together, they work to stimulate a robust CD4+ T cell response, prompting the components of the immune system to seek and destroy tumor cells.
To help T cells better recognize AE37, researcher
|Contact: Laura Sussman|
University of Texas M. D. Anderson Cancer Center