The Ii-Key technology in its cancer vaccine design and clinical trial data indicated that the AE37 breast cancer vaccine is safe, well tolerated. Furthermore, the vaccine results in a significant increase in specific anti-HER2 response with minimal toxicity. With a median follow-up of 22 months in breast cancer patients, Kaplan Meier projections estimate recurrence rates of 10% in vaccinated patients versus 17% in the control group, a risk reduction of 41%.
Of particular interest was the observation of a stronger reduction in relapse, from 31% in the control group to 11% in vaccinated patients (63% risk reduction), in patients with lower levels of HER2 expression. As these patients are not eligible for Herceptin therapy, they represent a significant area of unmet medical need.
A major obstacle in cancer immunotherapy is in educating the immune system to recognize tumor cells as foreign and destroying them as it does bacteria or viruses. While viruses can be inactivated and used themselves as a vaccine, tumor cells first require identification of appropriate tumor specific proteins (antigens) and then the technology to deliver those antigens such that the immune system recognizes them. Ii-Key technology fulfills this latter function. Advances in immunology have shown that specific activation of CD4+ T helper cells is critical for generating a robust and effective immune response. Modifying fragments of tumor specific proteins with Ii-Key dramatically improves their ability to activate CD4+ T helper cells to induce a specific and effective anti-cancer immune response.
"Results from the several clinical trials of AE37 provide convincing data validating the underlying Ii-Key technology, as well as setting the stage for a phase III trial of AE37," said Eric von Hofe, PhD, president of Antigen Express.
These results were presented as an abstract at ASCO and received the 2012 Conquer Cancer Foundation of ASCO Merit Award. The merit award program was established to recognize high quality clinical and scientific advancements.