Cancer vaccines are designed to train the immune system to attack cancer cells. To create a cancer vaccine candidate, we take antigens specific to cancer cells and combine them with a delivery vehicle such as a virus. The presence of a cancer antigen in the context of a viral “infection” alerts the immune system that the antigen is detrimental and should be eliminated from the body. Cancer vaccines have the potential to exhibit efficacy in their own right and may also pair optimally with our checkpoint platforms to elicit effective anti-cancer immune responses. This is expected to be particularly relevant in settings in which cancer cells are not recognized as “non-self” by the patient’s immune system.
Cancer vaccines are generally very tolerable so that they can be combined with traditional neoplastic therapies as well as with other immunotherapies such as checkpoint inhibitors. Some of the vaccines that we are developing include antigens specific to the tumors of a given patient. Others are “off-the-shelf” vaccines containing antigens we believe will be universal. Our vaccines are either based on specific mutations found in the tumor cells of an individual patient or on aberrantly phosphorylated proteins that are specific to different types of cancer and/or patients. These approaches allow us to create individualized cancer vaccines or off-the shelf vaccines.
Our vaccine platforms use our own proprietary vector systems that are based on heat shock proteins (HSPs), well-known surveyors of the proteins in the cell. HSPs are involved in transporting other proteins or smaller protein fragments from the interior of the cell to the cell surface for detection by the immune system. HSPs play a natural role in immune recognition of proteins unique to cancer.