Impact of Reduced Renal Function on the Glucose-Lowering Effects of Luseogliflozin, a Selective SGLT2 Inhibitor, Assessed by Continuous Glucose Monitoring in Japanese Patients with Type 2 Diabetes Mellitus

INTRODUCTION We investigated the impact of reduced renal function on 24-h glucose variability in Japanese patients with type 2 diabetes mellitus (T2DM) treated with luseogliflozin. METHODS In this double-blind, placebo-controlled, crossover study, 37 Japanese patients with T2DM [glycated hemoglobin (HbA1c) 7.0-10.0%] and estimated glomerular filtration rate (eGFR) ≥45 mL/min/1.73 m(2) were randomized into two groups in which patients first received luseogliflozin then placebo, or vice versa, for 7 days each. Twenty-four-hour glucose variability was measured on day 7 in each period and was compared among patients divided into three groups according to their baseline eGFR (mL/min/1.73 m(2)): normal (≥90; n = 13; normal group), normal-to-mildly reduced renal function (≥75 to <90; n = 12; normal-mild group), and mild-to-moderately reduced renal function (<75; n = 9; mild-moderate group). RESULTS The mean [95% confidence interval (CI)] placebo-subtracted 24-h cumulative urinary glucose excretion (g) was 82.1 (72.7, 91.5), 82.5 (73.4, 91.5), and 62.2 (51.2, 73.3); the placebo-subtracted 24-h mean glucose concentration (mg/dL) was -24.39 (-32.53, -16.26), -28.28 (-39.35, -17.22), and -11.53 (-23.93, 0.86); and the placebo-subtracted peak postprandial glucose (mg/dL) was -26.9 (-46.9, -6.9), -38.1 (-59.6, -16.6), and 1.5 (-25.5, 28.4) in the normal, normal-mild, and mild-moderate groups, respectively. The mean lowest glucose concentrations (placebo vs. luseogliflozin, mg/dL) decreased to similar levels in the normal (115.4 vs. 93.4), normal-mild (121.0 vs. 97.9), and mild-moderate (104.0 vs. 91.1) groups. CONCLUSION This post hoc subanalysis revealed that although mild-to-moderately reduced renal function attenuated the glucose-lowering effects of luseogliflozin on peak postprandial glucose, it did not attenuate the effects of luseogliflozin on fasting glucose. These findings may explain the smaller increase in urinary glucose excretion in these patients relative to patients with normal renal function or normal-to-moderately reduced renal function. Further studies may be needed to examine these findings in large populations of patients with T2DM and reduced renal function. TRIAL REGISTRATION JapicCTI-142548. FUNDING Taisho Pharmaceutical Co., Ltd.