Prior to empagliflozin introduction, the diagnosis of GSD-1b was confirmed by molecular analysis of the SLC37A4 gene, which revealed homozygous c.[1042_1043delCT];[1042_1043delCT] variant in Patient 1 (P1), compound heterozygous state c.[1109_1110delCT];[c.81T>A] genotype in Patient 2 (P2), and compound heterozygous state c.[547T>C];[530_531delTG] variants in Patient 3 (P3), with the latter variant being categorized as likely pathogenic. This evidence concerns the gene SLC37A4 and glycogen storage disease Ib.