Definition

A combination of three therapeutic cancer vaccines each containing a replication-defective, oncolytic adenoviral serotype 5 (Ad5) and each encoding a different tumor-associated antigen (TAA): human carcinoembryonic antigen (CEA), human glycoprotein mucin 1 (MUC1), and human transcription factor brachyury, with potential immunostimulating and antineoplastic activities. Upon subcutaneous administration, the Ad5 CEA/MUC1/brachyury vaccine Tri-Ad5 expresses the CEA, MUC1 and brachyury proteins. The expressed proteins may induce a cytotoxic T-lymphocyte (CTL)-mediated immune response against tumor cells expressing CEA, MUC1 and brachyury, thereby resulting in both immune-mediated inhibition of tumor cell proliferation and tumor cell death. CEA, MUC1 and brachyury are TAAs overexpressed in various tumor types. The Ad5 viral genes early 1 (E1), early 2b (E2b), and early 3 (E3) are deleted in Tri-Ad5, which prevents anti-adenovirus immune responses.