Stable recombinant MVA vectors comprising modified RSV genes with reduced intramolecular recombinatorial activity

A recombinant modified vaccinia Ankara (MVA) virus vector that stably encodes homologous sequences, the vector comprising:

• first and second nucleotide sequences of at least 1500 nucleotides each, each coding for at least 500 amino acids, wherein at least 150 continuous amino acids encoded by each of the two nucleotide sequences have at least 75% amino acid identity;
• wherein at least one of the first and second nucleotides has at least 400 substituted nucleotides and wherein the substituted nucleotides do not alter the identical amino acids encoded by said two nucleotide sequences;
• and
• wherein the first and second nucleotide sequences differ by at least 400 nucleotides;
• and
• wherein the first and second nucleotides share stretches of identity of no more than 9 contiguous nucleotides;
• and wherein the first and second nucleotide sequences each encode a RSV protein.