The present invention relates to a recombinant virus of the family Paramyxoviridae, comprising at least one expressible polynucleotide encoding an IL-12 polypeptide, wherein said IL-12 polypeptide is an IL-12 fusion polypeptide comprising a p35 subunit of an IL-12 and a p40 subunit of an IL-12; to a polynucleotide encoding the same, and to a kit comprising the same. Moreover, the present invention relates to a method for treating cancer in a subject afflicted with cancer, comprising contacting said subject with a recombinant virus of the family Paramyxoviridae of the invention, and thereby, treating cancer in a subject afflicted with cancer.