A proprietary cancer DNA vaccine that contains multiple natural and modified epitopes derived from the four tumor associated antigens, CEA, HER2/neu, p53, and MAGE 2/3. OSE 2101 also includes CAP1-6D, a heteroclitic CEA analog, and PADRE, a proprietary universal T-cell epitope that serves to enhance the immunogenicity of the epitopes. This agent has been shown to elicit cytotoxic T-lymphocyte responses against tumor cells expressing these multiple epitopes.