Clinical Trials with a Polyvalent Breast cancer Vaccine

摘要

MUC1 and Le(sup Y) are cell surface antigens expressed on a variety of epithelial cancers including cancers of the breast and ovary. They would appear to be excellent targets for antibody inducing vaccines. MUC1 and Le(sup Y) vaccines prepared and tested over the last 4 years have resulted in high titer antibodies against the synthetic antigens which were of relatively modest titer against tumor cells expressing these antigens. While these vaccines could be included in future polyvalent vaccines, it was our impression that we could augment the relevant immunogenicity by using longer MUC1 peptides or glycosylated peptides, or by using Le(sub Y) vaccines with a higher Le(sup Y)/ KLH epitope ratio. Consequently, a series of second generation MUC1 and Le% vaccines have been prepared, tested for safety and immunogenicity in mice and are now in clinical trials. Trials with the first two, a longer MUC1 peptide (106aa) and a glycosylated version of this longer MUC1 peptide, have been completed and the serologic results are not better than with the original shorter, unglycosylated MUC1. Results of the currently ongoing trials with shorter glycosylated MUC1 peptides and with the higher epitope ratio Le(sup Y) are not yet available.