Ipragliflozin, a SGLT2 Inhibitor, Reduced Body Weight and Fat Mass but Not Muscle Mass in Japanese Type 2 Diabetic Patients Treated with Insulin—A Randomized Clinical Trial

Objective: Weight gain is a common problem in the insulin treatment. SGLT2 inhibitors are expected to reduce body weight (BW) due to negative energy balance. Previous reports suggested that BW reduction is achieved mainly by loss of body fat, and ∼20% of reduction is by lean mass. However, the efficacy of SGLT2 inhibitor on BW and body composition remains unclear. We examined these in the Japanese T2DM treated with insulin. Methods: The study was an open label randomized controlled trial. Primary endpoint was the change in BW from baseline to week 24 between the two groups. Fifty overweight patients (BMI > 23) who had inadequate glycemic control with insulin treatment were randomly assigned to ipragliflozin (Ipra) or standard treatment (Con) and followed for 24 weeks. Body composition was assessed by DEXA and impedance method. Results: The change in BW was significantly larger in Ipra compared to Con. Ipra showed significant larger reduction of HbA1c. Total fat mass was reduced in the Ipra compared to Con mainly due to lower limb fat and trunk fat. Total muscle mass was maintained at lower limbs and trunk but tended to be reduced at arm in Ipra. Conclusion: Ipragliflozin treatment for 24 weeks resulted in reduction of BW mainly due to fat mass at lower limb and trunk. Reduction of the muscle mass at lower limb may be protected by anti-gravity effect.