Sodium–glucose cotransporter 2 inhibitor, tofogliflozin, shows better improvements of blood glucose and insulin secretion in patients with high insulin levels at baseline

AIMS/INTRODUCTION: Sodium glucose cotransporter 2 (SGLT2) inhibitors are a new class of drugs for the treatment of type 2 diabetes mellitus that improve control of plasma glucose and bodyweight, giving great hope for the clinical utility of these agents. However, it is unclear for which patients SGLT2 inhibitors will be useful. MATERIALS AND METHODS: We analyzed data from long‐term tofogliflozin monotherapy in an open‐label, randomized controlled trial in Japanese patients with type 2 diabetes mellitus. Patients were divided into tertiles by baseline insulin level: group low (L): insulin ≤5.6 μU/mL, group medium (M): 5.6< insulin ≤10 μU/mL and group high (H): insulin >10 μU/mL. RESULTS: Glycated hemoglobin and fasting plasma glucose levels, along with bodyweight, were significantly reduced from the baseline in all groups. The changes in levels of plasma glucose area under the curve for 2 h, C‐peptide index area under the curve for 2 h during the meal tolerance tests and the insulin secretion index were the largest in the H group. The incidence of drug‐related adverse events was not different among the three groups. DISCUSSION: Although tofogliflozin was effective regardless of baseline insulin level, it showed the highest efficacy in the H group.