A whole, heat-killed, recombinant Saccharomyces cerevisiae yeast-based vaccine genetically altered to express the carcinoembryonic antigen (CEA) peptide 610D with potential immunostimulating and antineoplastic activities. Upon administration, recombinant Saccharomyces cerevisia-CEA(610D) vaccine GI-6207 may stimulate a host cytotoxic T-lymphocyte (CTL) response against CEA-expressing tumour cells, which may result in tumour cell lysis. CEA, a tumour associated antigen, is overexpressed on a wide variety of human cancer cells including colorectal, gastric, lung, breast and pancreatic cancer cells. CEA 610D encodes for 9 amino acids (605-613) in which aspartate is substituted for asparagine at position 610 (610D) in order to strengthen the induction of the CTL response against CEA-expressing tumour cells.