There is described a kit for use in inducing an immune response in a mammal, the kit includes: a first virus that expresses MAGEA3, Human Papilloma Virus E6/E7 fusion protein, human Six-Transmembrane Epithelial Antigen of the Prostate protein, or Cancer Testis Antigen 1, or a variant thereof as an antigenic protein and that is formulated to generate an immunity to the protein or variant thereof in the mammal. The kit also includes a Maraba MG1 virus encoding the same antigen, or a variant of the same antigen. The Maraba MG1 virus is formulated to induce the immune response in the mammal. The first virus is immunologically distinct from the Maraba MG1 virus
