| CPC A61K 39/12 (2013.01) [A61K 9/0019 (2013.01); A61K 2039/53 (2013.01); A61K 2039/55555 (2013.01)] | 14 Claims | 

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               1. A messenger ribonucleic acid (mRNA) comprising an open reading frame (ORF) encoding a prefusion respiratory syncytial virus (RSV) F protein, wherein the ORF encodes an amino acid sequence having at least 95% identity to the amino acid sequence of SEQ ID NO: 5, wherein identity defines the percentage of amino acid residues in the RSV F protein that are identical to residues of SEQ ID NO: 5 after introducing any necessary gaps to align the two full-length sequences. 
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