Objective and Methods : A long-term effect of ipragliflozin on adipose tissue mass reduction in Japanese patients with obese type 2 diabetes (T2D) was investigated. Ipragliflozin was administered (50mg/day) once daily for 12 months. At 0, 3, 6 and 12 months, visceral and subcutaneous adipose tissue area was determined by two different bioelectrical impedance methods, and blood samples for HbA1c, renal function, lipids and liver function obtained, and body weight and blood pressure recorded. The primary endpoint was decrease in body fat mass. Secondary endpoints included changes in body weight and the laboratory data.
Results : Seventeen of 20 participants (mean body mass index (BMI) 35.1±1.1 kg/m²) completed this prospective observational study. Visceral fat area (cm², mean±SD) at 0, 3, 6 and 12 months was 166.0±49.7, 149.7±46.1, 149.7±42.4 and 148.5±40.2, respectively : the value at 3 months was significantly lower than baseline (P＝0.027). Subcutaneous fat at the corresponding time points was 359.3±110.5, 316.6±87.1, 326.8±87.2 and 325.9±90.4, respectively : the values at each post treatment period was significantly less than the baseline (P＝0.003, 0.018 and 0.036 for the three points, respectively). Body weight was significantly reduced by 12 months (P＝0.045). Serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), and γ-glutamyl transpeptidase (γ-GTP) levels decreased significantly. There were no significant correlations between serum hepatobiliary enzyme levels and Δbody weight or Δvisceral fat, but Δγ-GTP was correlated with Δsubcutaneous fat (Spearman's P＝0.004).
Conclusion : During the 1 year interval, ipragliflozin significantly reduced subcutaneous adipose tissue and serum AST, ALT, and γ-GTP levels.