US Patent 11597742 Crystalline forms of (S)-2-ethylbutyl 2-(((S)-(((2R,3S,4R,5R)-5-(4-aminopyrrolo[2,1-f] [1,2,4]triazin-7-yl)-5-cyano-3,4-dihydroxytetrahydrofuran-2-yl)methoxy) (phenoxy) phosphoryl)amino)propanoate

The present invention relates to novel salts and crystalline forms of (S)-2-ethylbutyl 2-(((S)-(((2R,3S,4R,5R)-5-(4-aminopyrrolo[2,1-f][1,2,4]triazin-7-yl)-5-cyano-3,4-dihydroxytetrahydrofuran-2-yl)methoxy)(phenoxy)phosphoryl)amino)propanoate for use in treating viral infections. In some embodiments, the viral infection is caused by a virus selected from the group consisting of Arenaviridae, Coronaviridae, Filoviridae, Flaviviridae, and Paramyxoviridae.