Ipragliflozin versus metformin for blood sugar control and fat reduction in type 2 diabetes

The aim of this study was to compare the effectiveness of ipragliflozin compared to metformin in improving blood sugar control and reducing fat on organs in patients with type 2 diabetes (T2D) treated with sitagliptin. The main finding of the study was that ipragliflozin had greater reductions in fat but metformin had better blood sugar control.

There are many different medications used to treat T2D. Different drugs are used in a different order all over the world. For example, in the United States and Europe, metformin (Glucophage) is used first. If blood sugar is not controlled with metformin, other drugs are added such as DPP-4 inhibitors or SGLT2-inhibitors. DPP-4 inhibitors (DPP-4i) include sitagliptin (Januvia), Vildagliptin (Galvus), Saxagliptin (Onglyza), Linagliptin (Tradjenta. SGLT2 inhibitors include drugs such as ipragliflozin (Suglat). In Asia, DPP-4is are used first and metformin is added after. The best combination of these drugs remains unclear.

When fat accumulates in the body, it gets deposited on some organs such as the liver and pancreas (the organ that controls blood sugar). This is called visceral fat (VF). VF causes these organs to not work properly and therefore blood sugar is not controlled.

It is not known which of the diabetic medications is better at reducing VF and improving blood sugar.

This study included 98 patients with T2D and were taking a DPP-4is (sitagliptin). Patients were randomly assigned to receive either ipragliflozin 50mg daily or metformin 500mg daily (increased to 1000 daily after 2-4 weeks). Patients were treated for 24 weeks.

After 24 weeks, the ipragliflozin group had significantly greater reductions in VF than the metformin group. They also had significantly greater reductions in body weight and waist measurements. However, the metformin group had significantly greater reductions in their HbA1c (blood test measuring average blood sugar control over the past 3 months) than the ipragliflozin group. The metformin group also had significantly greater decreases in their LDL cholesterol (“bad cholesterol”. The ipragliflozin had an increase in both LDL cholesterol and HDL cholesterol (“good cholesterol). The ipragliflozin group also had greater reductions in the amount of fats in the blood.

The authors concluded that ipragliflozin was better in reducing organ fat whereas metformin was better at improving blood sugar control and cholesterol in patients with T2D treated with sitagliptin.

This study had a very small number of patients and only included Japanese patients. Different ethnicities have different responses to medications. Larger studies are needed for more solid evidence.