The study used mixed effects modeling to extrapolate the pharmacokinetics of empagliflozin from adults to children ≥15 kg with heart failure. They identified a two-compartment model with an allometric change in clearance parameters and weight distribution. At 10 mg in a 15 kg child, they achieved a median AUC ratio of 1.03 (interquartile range 0.82–1.30) versus a 50 kg adult at 25 mg (median 7,385,163 nmolh/l). They proposed an optimal sampling scheme for a study with 12 patients in 4 groups. This design allows drug exposure to be characterized and safety and efficacy data to be collected. The protocol envisages the extrapolation of the cardioprotective mechanisms of SGLT-2 inhibitors from adults to children. The results support the use of 10 mg tablets in children weighing ≥ 15 kg.