Parkinson J, et al. - In this investigation, researchers quantitatively characterized the association between systemic exposure to dapagliflozin and response to glycated hemoglobin (HbA1c) in patients with type 1 diabetes mellitus (T1DM) and evaluated the possible influence of the effects of covariates. Using a non-linear mixed effect modelling approach, individual longitudinal HbA1c data from two phase 3 studies in patients with T1DM (24-week treatment with once-daily dapagliflozin 5 or 10 mg or placebo, with adjustable insulin) were assessed. The data presented in this work showed a maximum effect (E_max) model found a positive exposure-response association. In patients with T1DM, the connection between dapagliflozin systemic exposure and HbA1c response was effectively characterized. None of the covariates tested had a clinically relevant impact on the efficacy of dapagliflozin; patients with T1DM do not need to adjust the dose of dapagliflozin based on the covariates tested.