Then, the monophosphate is transformed to guanosine analog by adenosine deaminase like protein 1 (ADALP1) and further phosphorylated by guanylate kinase 1 (GUK1) and nucleoside diphosphate kinase (NDPK) to the pharmacologically active form of AT-527 diphosphate (also reported as AT-9010) (Figure S3) [78].